Generation IV Internal Engine - LS road race/autox Motor choices




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pharmd
06-07-2012, 07:24 AM
Contemplating 2 engine combo's ( 1 lower cost, 1 higher cost). I don't plan to run in a "class" so Im not capped with cubes or power limits. I have access to an LS1 block or LS2 block from which to start (unless I purchase something different which may or may not be cost effective). The motor needs to be rock solid durable. I plan to run an accusump and road race oil pan. The guys Im gonna be running with/against, have some crazy setups, I realize it will take cubic dollars to be competitive...but if I can just get in the mix, with a decent power plant I'll be happy.


Option 1: Rebuilt LS1 with stock crank, rods (arp bolts), forged pistons, AI TFS heads, 231/239 112 cam, FAST 102 Intake/TB, ARH 1 7/8" headers, accusump, RR oil pan with filter relocation. ~ cost $3500 (i already have several of the above parts from my previous build).

OPtion 2: Stroked LS2 (408), K1 crank, Scat Ultralight rods, JE pistons, Morel lifters, YT rockers, custom cam, AI TFS 230cc heads, Fast 102 intake/TB, ARH 1 7/8" headers, accusump, RR oil pan with filter relocation. ~$10,000

I have several other ancillary parts to buy, like brakes, sways, springs, wheels/tires...so I'm leaning towards the option 1....The previous setup made 456/415 on a conservative dyno, I figure with forged piston choice and the AI TFS heads, I could pick up a few more hp, and maintain good AUC TQ. It would put me real close to 475-480rwhp, and IMHO that would be fairly competitive with the guys I'm running with.

Thoughts?


got milk??
06-07-2012, 08:53 AM
Both of those setups are stout, but autoX is more about the total package than raw power. Your suspension/ wheel, tire combo is equally if not more important than a 480hp motor. You should send Sam Strano a PM or email and get his input/advice. The guy has decades of autoX time under his belt.

3.4camaro
06-07-2012, 09:31 AM
If I were building a road race motor, I'd be looking to spin high rpms.

I'd bore out the motor to the largest bore possible, with a short stroke crank(stock LS1 or maybe 4.8L). This way, you're getting maximum cubes and not over doing it on the piston speed. Piston speed is what melts rings and causes damage and undue wear.

This setup also allows for the largest valve size among your options, so you'll be achieving the highest airflow.

Since you're posting this in the Gen4 section, I'd recommend you get an LS3 block so you can get them fancy piston oil squirters installed. Put that dry sump to good use, and keep those fancy pistons of your VERY cool.


Che70velle
06-07-2012, 06:04 PM
Road course and auto cross is two entirely different animals. Road course racing is very fast paced, high rpm racing with crazy top speeds. It is endurance racing at its finest. Auto cross on the other hand, is all about suspension set up with an occasional full throttle stab. Tire choice and brakes are huge benefactors, with throttle control being king. Both of these styles of racing have some similarities, but are also very different engine wise. You won't win an autocross with the most power. I watched Kyle Tucker just this past weekend at the LSX shootout autocross, and many others, and it's finess racing. I raced NASCAR late models for many years across the street from Road Atlanta, and I can tell you road racing is very extreme. I'm building my chevelle for autocross, and street use.

pharmd
06-07-2012, 10:29 PM
I have an LS1 block AND LS2 block...We are leaning towards building the LS2 with stock crank, forged rods/pistons, AI TFS heads, COMP rockers, Morel lifters, FAST 102 intake/TB. We think that we will be between 480-500rwhp and 430-450rwtq. I may use my current cam 231/239 113 and advance it some (its retarted 5 deg now), or go with a custom grind...just depends on what Phil thinks are the trade offs.

My LS1 made good power, but I think I had oil control issues...I will be resolving with an accusump, and road race oil pan.

Any arguments for the stock cube LS2 build vs the 408 LS2 build? Does the power difference justify the cost?

Tainted
06-07-2012, 11:28 PM
Theres no replacement for displacement and bigger bore, with a better platform, and more hp and tq to start with. Ls2 all the way

crainholio
06-08-2012, 06:04 AM
If I were building a road race motor, I'd be looking to spin high rpms.


Not so much, if you want the engine to last. Or to make power on corner exit where you need it.

pharmd
06-08-2012, 07:18 AM
Not so much, if you want the engine to last. Or to make power on corner exit where you need it.

agreed...awesome TQ from 3K on, with good HP from 3000-6000 would be very adequate. I think with how much of a focus AI keeps on port velocity and chamber efficiency, with the right CR, it will meet those goals.

garcr4
06-09-2012, 07:57 AM
We have been racing LS motors in stock cars our Corvette and tube frame Camaro for years.

A few observations:

Torque seems to be king in most road race applications as long as you can hook it up.
Our torquey 5.7 LS1 motors have won races and set track records at times utilizing very mild set ups: stock compression LS1's with headers, ASA hot cam, ECU tuned by Schwanke or Carb version with MSD 6LS. These motors made between 450-480 flywheel HP and turn about 6500-6800 rpm. Our 2800 pound with driver tube frame Camaro with a 480 HP LS1 turned a 1:56.9 at Daytona with a top speed of 182 mph in the trioval and beat a lot of higher HP GT-1 cars.

We have used the single stage scavenge dry sump system with success. It uses the stock pressure pump, has a three gallon dry sump tank and a Moroso ASA dry sump oil pan. This system worked well in the old ASA AC Delco series. Some used their motors for several years, sold the cars to road racers, where the motors lasted several more years.

that said, a full dry sump system is preferrable!

Anything less than this is asking for trouble if you are running sticky road race tires with high corner G's. The accusump deal is a bandaid.

3.4camaro
06-09-2012, 10:56 AM
Not so much, if you want the engine to last. Or to make power on corner exit where you need it.

A properly built, dry sump engine would have no problem spinning to 8000rpm. If the valvetrain is lightweight and properly set up, you'll be just fine.

You'd need driving lessons if you don't know how to be in the right gear when leaving a corner.

Why are you against high rpms?

crainholio
06-09-2012, 02:24 PM
A properly built, dry sump engine would have no problem spinning to 8000rpm. If the valvetrain is lightweight and properly set up, you'll be just fine.

You'd need driving lessons if you don't know how to be in the right gear when leaving a corner.

Why are you against high rpms?

Over 7 years experience between offshore and ARCA here. What is the source of your expertise?

Post the Grand Am, ALMS, or other endurance racing team doing what you're describing with LS engines...or are you just reading magazines and barfing up assumptions?

3.4camaro
06-09-2012, 03:43 PM
http://speedtalk.com/forum/viewtopic.php?p=150911

"The CTSV dominated the first races, not only did the sanctioning body enforce an RPM limit on the short stoke Caddies but they eventually implemented more restrictions to limit the horsepower on these LS7 equipped 346ci engines. "

It's clear that high rpms with short strokes win races. Look at F1 as another example. Now, what exactly are you talking down to me for?

Go ahead and answer my first question: What do you have against high rpm motors?

garcr4
06-09-2012, 04:11 PM
You can win races with torque or with rpm hp, but certainly twisting LS motors in the 8000 rpm range is gonna require expensive rebuilds much sooner. SCCA GT-1/Trans Am motors make over 800 hp and twist in the 9000 rpm range. But they are used up in 600 miles, requiring many new and expensive parts for the rebuild.

If you are on a club racers budget the wiser move would be to use the inherent torque of the LS design and cam for 7000 rpm or less.

The AlMS Corvettes turn less than 7000 rpm but make incredible torque and their lap times don't suffer.

I watched at Daytona last year at the HSR race and saw a front running Trans Am car with SB2 twisting around 9000 rpm (840 hp) with a race weight of 2780 with driver turn a 1:47 lap. During the same race a World Challenge Corvette at about 3150 running a torquey LS2 6.0 (maybe 600 hp) liter cut a 1:48

JD_AMG
06-09-2012, 05:12 PM
http://speedtalk.com/forum/viewtopic.php?p=150911

"The CTSV dominated the first races, not only did the sanctioning body enforce an RPM limit on the short stoke Caddies but they eventually implemented more restrictions to limit the horsepower on these LS7 equipped 346ci engines. "

It's clear that high rpms with short strokes win races. Look at F1 as another example. Now, what exactly are you talking down to me for?

Go ahead and answer my first question: What do you have against high rpm motors?

I have to lol at this...
The only reason you are seeing high RPMs is because those classes have displacement limitations. So they HAVE TO rev higher if they want to make more power.
There is absolutely no reason to spend all the extra money on building the engine to turn 8000RPMs, that money could be spent making more power with less RPMs...

Bink
06-09-2012, 07:17 PM
I have to lol at this...
The only reason you are seeing high RPMs is because those classes have displacement limitations. So they HAVE TO rev higher if they want to make more power.
There is absolutely no reason to spend all the extra money on building the engine to turn 8000RPMs, that money could be spent making more power with less RPMs...

Yep. :D

Also, follow garcr4 advice - he's a builder and a road racer. :D

crainholio
06-09-2012, 08:35 PM
It's clear that high rpms with short strokes win races. Look at F1 as another example.


I suppose I missed the OP's stated intent to compete in F-1 or build a short-stroke engine...go back and re-read the two options he was considering.

And your quote of the current CTS-V program overlooks quite a bit of background. When they fielded that car in the mid-2000's it was running a 7.0L stroker, same displacement as the C5.R program. On most tracks they weren't even breaking 6K RPMs, and were winning races. Then came homologation rule changes and less displacement...



Now, what exactly are you talking down to me for?


How many endurance racing engines have you built and put on a track? You're giving advice, so you must have experience from which you're drawing...or are you another Intarwebz Expert regurgitating magazine articles?


Go ahead and answer my first question: What do you have against high rpm motors?

I already did. Go ahead and re-read my first response to your post, in the context of the options the OP was considering. High-revving engine setup does not fit his requirement for durability.

And the kind of induction setup and cam that would make power at high revs takes away from midrange torque.

If he's not running a $20K sequential trans, the extra downshift(s) to keep the peaky high-rev engine making power out of the corners will cost him plenty versus the guy who can run the same course using only gears 3 & 4.

pharmd
06-10-2012, 10:14 PM
We have been racing LS motors in stock cars our Corvette and tube frame Camaro for years.

A few observations:

Torque seems to be king in most road race applications as long as you can hook it up.
Our torquey 5.7 LS1 motors have won races and set track records at times utilizing very mild set ups: stock compression LS1's with headers, ASA hot cam, ECU tuned by Schwanke or Carb version with MSD 6LS. These motors made between 450-480 flywheel HP and turn about 6500-6800 rpm. Our 2800 pound with driver tube frame Camaro with a 480 HP LS1 turned a 1:56.9 at Daytona with a top speed of 182 mph in the trioval and beat a lot of higher HP GT-1 cars.

We have used the single stage scavenge dry sump system with success. It uses the stock pressure pump, has a three gallon dry sump tank and a Moroso ASA dry sump oil pan. This system worked well in the old ASA AC Delco series. Some used their motors for several years, sold the cars to road racers, where the motors lasted several more years.

that said, a full dry sump system is preferrable!

Anything less than this is asking for trouble if you are running sticky road race tires with high corner G's. The accusump deal is a bandaid.

Do you have a product recommendation on this? I was under the impression by adding a road race oil pan, along with oil cooler, remote mount filter, and Canton accusump I would pretty much be covered for oil control...but if Im not covered, I need to know how to cover myself. If I build the LS1 or use the LS2 block and build that motor, what options do I have (affordable options preferred).

gnx7
06-11-2012, 01:03 AM
3.4 Camaro must have more money than brains.... :)

RPMs kill motors. The brighter it burns.... the less amount of time it lasts. No need to rev past 7K on a road race setup for longevity unless you have GM's bank account for frequent rebuilds.

I have an SCCA ITE car (unlimited) that runs a 438ci stroker (LS7 with 4.1" crank) and it sees a 6600rpm redline. Could it rev to 7Krpm+..... yes.... but the wide torque band is used to run a GForce GSR 4spd dogbox and 3.27 rear gear with 13" rear wide slicks. It is actually driven as a 3speed as 1st is only used to get moving. The car puts the power down everywhere and simply keeps pulling. Mine is only 2470lbs with 7 gallons of fuel... but it gets around the track in a hurry. My complete clutch/flywheel combo is only 13lbs. Triple disc Quartermaster setup. Revs instantly.

Build the largest displacement engine you can with the most compression possible and then gear it appropriately and put massive tires on the car or at least the stickiest tire you are allowed to run. Dry sump if you can afford it or an Accusump and overfill with 1 quart plus trap door/pan baffle setup minimum. I run an ARE multi stage dry sump pan with Aviad pump and 3 gallon sump behind a firewall in the passenger side area.

IMO if you are limited to an LS2 block than run some TFS 225cc as cast heads with Brian Tooley touch up work (ex-TEA porting guru) and FAST 102mm intake. If you need his contact info LMK. Consider a 4.1" crank also. No need for Morels... I'm running $100 CTS-V GM lifters and stock rebuilt Comp Cams trunion rocker arms. If you are on a budget skip the FAST and run an LS6 intake as you don't need to wind out this motor. A straight shot intake with no bends will add 10-15rwhp.

Next will be track time to learn the car and punish what you have to work with. :angel:

garcr4
06-11-2012, 08:01 AM
Do you have a product recommendation on this? I was under the impression by adding a road race oil pan, along with oil cooler, remote mount filter, and Canton accusump I would pretty much be covered for oil control...but if Im not covered, I need to know how to cover myself. If I build the LS1 or use the LS2 block and build that motor, what options do I have (affordable options preferred).

ARE, AVIAD, and DAILY all make nice dry sump systems for LS Motors.

My Corvette uses an ARE pan, with a Barnes single stage pump set up from Schwanke.

Our Camaro uses the ASA Moroso pan that was on the Lingenfelter LS1's run in ASA AC Delco stock car series. I have one of those set ups for sale if you are interested. They used a RAZOR single stage pump.

LSfan70s
06-12-2012, 12:13 PM
Awesome post. Thanks for sharing all the good info.

Is there any recipe for the LS's engines scavenge only dry sump pulley sizes? This is for budget/get all parts one by one project. I read somewhere that a 50% relation would be fine, but I can't confirm. Any guidance is highly appreciated. :thumb:

pharmd
06-12-2012, 01:12 PM
3.4 Camaro must have more money than brains.... :)

RPMs kill motors. The brighter it burns.... the less amount of time it lasts. No need to rev past 7K on a road race setup for longevity unless you have GM's bank account for frequent rebuilds.

I have an SCCA ITE car (unlimited) that runs a 438ci stroker (LS7 with 4.1" crank) and it sees a 6600rpm redline. Could it rev to 7Krpm+..... yes.... but the wide torque band is used to run a GForce GSR 4spd dogbox and 3.27 rear gear with 13" rear wide slicks. It is actually driven as a 3speed as 1st is only used to get moving. The car puts the power down everywhere and simply keeps pulling. Mine is only 2470lbs with 7 gallons of fuel... but it gets around the track in a hurry. My complete clutch/flywheel combo is only 13lbs. Triple disc Quartermaster setup. Revs instantly.

Build the largest displacement engine you can with the most compression possible and then gear it appropriately and put massive tires on the car or at least the stickiest tire you are allowed to run. Dry sump if you can afford it or an Accusump and overfill with 1 quart plus trap door/pan baffle setup minimum. I run an ARE multi stage dry sump pan with Aviad pump and 3 gallon sump behind a firewall in the passenger side area.

IMO if you are limited to an LS2 block than run some TFS 225cc as cast heads with Brian Tooley touch up work (ex-TEA porting guru) and FAST 102mm intake. If you need his contact info LMK. Consider a 4.1" crank also. No need for Morels... I'm running $100 CTS-V GM lifters and stock rebuilt Comp Cams trunion rocker arms. If you are on a budget skip the FAST and run an LS6 intake as you don't need to wind out this motor. A straight shot intake with no bends will add 10-15rwhp.

Next will be track time to learn the car and punish what you have to work with. :angel:

I was under the impression that you would want a short stroke for this type of situation. Something that combines mid-range TQ with suspension setup and tire, such that you have an optimal blend of traction and power.

The decision is really between doing an LS1 budget motor, or rebuilding my LS2. The price difference will likely be about $3500, but the power difference not as great? I wanted to get a solid combo up and going for now, then in a couple years build a nice motor.

garcr4
06-12-2012, 03:24 PM
Awesome post. Thanks for sharing all the good info.

Is there any recipe for the LS's engines scavenge only dry sump pulley sizes? This is for budget/get all parts one by one project. I read somewhere that a 50% relation would be fine, but I can't confirm. Any guidance is highly appreciated. :thumb:

Mine all have the hub/pulley that mates to ATI damper. Probably an ATI piece.

The guy that I know that could best answer your questions would be Tim Schwanke at Schwanke Racing Engines as he has built a lot of single and multi stage dry sump LS systems.

"Bosco"

WKMCD
06-12-2012, 03:52 PM
Finally some good tech info on LS1"tech". Hang around long enough it pops up from time to time.

Thanks!

SSCamaro99_3
06-12-2012, 04:07 PM
I was under the impression that you would want a short stroke for this type of situation. Something that combines mid-range TQ with suspension setup and tire, such that you have an optimal blend of traction and power.


Depends on class rules. In the 1990's Oldsmobile was racing in a Road Course Series (ALMS, Pirelli Challenge, can't quite remember). The engine rules were not restricted for displacement. They ran BBC's in the 600+ CI range and did not spin the hell out of them. They swithced to an Aurora based engine near the end of the series. If you have a displacement limit, then you want as much bore as you can, within the confines of the block, at the expense of stroke. That way you can maximize the effectiviness of the displacment.

That's why Cup cars are around 4.185x3.25 or 4.25x3.15, been awhile since I looked into it.

garcr4
06-13-2012, 02:54 PM
Depends on class rules. In the 1990's Oldsmobile was racing in a Road Course Series (ALMS, Pirelli Challenge, can't quite remember). The engine rules were not restricted for displacement. They ran BBC's in the 600+ CI range and did not spin the hell out of them. They swithced to an Aurora based engine near the end of the series. If you have a displacement limit, then you want as much bore as you can, within the confines of the block, at the expense of stroke. That way you can maximize the effectiviness of the displacment.

That's why Cup cars are around 4.125x3.25 or 4.25x3.15, been awhile since I looked into it.

Olds was racing in IMSA Camel GT in the 90's with Cutlass's built by Irv Hoerr, Tommy Riggins and others. These cars were using small block chevy's with about 366 ci making in the neighborhood of 650 hp on the engine dyno. Most utilized the Chevy Bow Tie 18 degree cylinder heads as used in Nascar at the time. Later Olds campaigned the Aurora's using the Aurora V8 I believe. These were tube framed GT cars weighing about 2800 pounds with driver, very similar to Trans Am cars

jbhotrod
06-14-2012, 12:28 AM
Im not a racer and dont know much about road racing but I love watching it and would love to be involved in it. My dad recently became friends with a guy whose son races Porsche GT3s in the ALMS and other series though and the guy wants my dad to help him get into drag racing. He is setting up a 69 Camaro with a 572 BBC that put down 899hp. He wants my dad to work on the car for him and help get set up at the track. Hopefully that could maybe turn into some type of connection and possibly get my foot in the door into the racing business and possible job opportunity down the road though I hope Im not speaking too soon(knock on wood). I dream of getting ANY type of job on a racing team like that! LOL

But anyway FWIW I remember reading something about the Dodge Vipers being limited to 5000rpm or something like that for Le Mans but they still did well and I know this is a crappy source so dont flame me but on Forza the Viper race cars were limited to 6000rpm or less I wanna say.

And I know its not road racing but the tracks are similar as far as turns/straights, I raced motocross for half my life and always have been/will be a die hard 2-stroke lover but the 4-strokes have taken. Excluding my opinion that they were favored by the manufacturers to take over due to more $$$ and the EPA being involved so the 4-strokes were given way to much displacement advantage. In reality it shouldve been 125 2-stroke vs ~185-200cc 4-strokes and 250cc 2-strokes vs ~330cc 4-strokes. Anyway the reason the 4-strokes took over is due to the power curve. Early on the 2-strokes were making MORE peak power than the 4-strokes but the power curve of them makes it much easier to ride faster. You can be in a gear too high and it dont matter while with a 2St if youre a gear too high it falls on its face and youll likely case the next jump and bust your balls. Same thing happened in MotoGP with the 500s vs 990s.

I realize a 2-stroke is a much more exagerrated example though as if youre not at the right rpm you arent going anywhere. But, I figured it may translate just a little bit to what yall are saying. Sorry for the essay but I just wanted to see if my insight may help a bit to people who dont understand...

pharmd
06-14-2012, 07:00 AM
So is their any REAL need a forged crank on this type of motor...If you budget oriented what components are MUST have upgrades?

Seems to me like the stock LS2 crank would be adequate, maybe even stock rods with upgraded bolts, Forged/coated pistons are probably a smart upgrade, as would be rocker upgrade (trunion upgrade minimum), good pushrods, better lifters.

Anyone have anything they think needs to be added? Are these thoughts accurate?

garcr4
06-15-2012, 07:57 AM
So is their any REAL need a forged crank on this type of motor...If you budget oriented what components are MUST have upgrades?

Seems to me like the stock LS2 crank would be adequate, maybe even stock rods with upgraded bolts, Forged/coated pistons are probably a smart upgrade, as would be rocker upgrade (trunion upgrade minimum), good pushrods, better lifters.

Anyone have anything they think needs to be added? Are these thoughts accurate?

We have had no problems road racing with stock cranks and stock rods up to about the 500 HP level on an engine dyno. All of our motors have had forged pistons. If you are only gonna spin these motors in the 6500-6800 range you should be ok. We have always used the ARP rod bolts. We have had one stock rocker failure and have since gone to the comp cams trunion upgrade. I believe they use these on the Nascar K&N Series LS2 motors.

Bink
06-15-2012, 11:35 AM
Mine all have the hub/pulley that mates to ATI damper. Probably an ATI piece.

The guy that I know that could best answer your questions would be Tim Schwanke at Schwanke Racing Engines as he has built a lot of single and multi stage dry sump LS systems.

"Bosco"

Bosco - I recognized you from the info in your posts. Could you place your nickname in your sig so these guys know who you? :)

Your real-world experience and knowledge is greatly appreciated by all. :D

garcr4
06-16-2012, 07:55 AM
Bosco - I recognized you from the info in your posts. Could you place your nickname in your sig so these guys know who you? :)

Your real-world experience and knowledge is greatly appreciated by all. :D

I would if I could figure out how to add it.


OK, figured it out

garcr4
06-16-2012, 08:11 AM
For what it is worth here is our Grand Am type Vette. Much to poor to actually run it in Grand Am, but we have one none the less.
The only things there that are Corvette are the body and the LS6. It is a tube frame, with Nascar Jerico tranny and nine inch rear end. Nascar Brembo's etc. Below is our team Camaro.....Howe chassis and Howe body, carbureted 383 LS6, 570 HP.

http://i641.photobucket.com/albums/uu132/bosco022/100_0528.jpg

http://i641.photobucket.com/albums/uu132/bosco022/BemcoCamaroDISSept26.jpg

Che70velle
06-17-2012, 01:26 PM
Are you with the GARC guys out of Alabama?

Jenson
06-17-2012, 01:55 PM
We have 2 guys with stock cranks that rev to 11k rpm (2.0L), forged is for a lot of power/rpm. Daily is the place to go!! They made us a new from scratch billet dry sump pan in 7 days a couple years ago. I'm in a similar situation trying to decide on a dry sumped LS1 rebuild or sleeve it for max cubes and use LS7 heads.

garcr4
06-17-2012, 03:27 PM
No, my cars have been built by Woody Wood of Bemco Fabrication in Deland Fl.
Woody is a former ASA AC Delco and Championship winning ARCA crew chief for many well known racers and a former Nascar Cup crewman. Woody has more than 30 years experience building race cars of all types.
Are you with the GARC guys out of Alabama?

jbhotrod
06-19-2012, 02:52 PM
For what it is worth here is our Grand Am type Vette. Much to poor to actually run it in Grand Am, but we have one none the less.
The only things there that are Corvette are the body and the LS6. It is a tube frame, with Nascar Jerico tranny and nine inch rear end. Nascar Brembo's etc. Below is our team Camaro.....Howe chassis and Howe body, carbureted 383 LS6, 570 HP.

http://i641.photobucket.com/albums/uu132/bosco022/100_0528.jpg

http://i641.photobucket.com/albums/uu132/bosco022/BemcoCamaroDISSept26.jpg

Wow, the Corvette is hot! If its not a secret, care to show us what the rear suspension setup looks like?

pharmd
06-19-2012, 08:27 PM
For what it is worth here is our Grand Am type Vette. Much to poor to actually run it in Grand Am, but we have one none the less.
The only things there that are Corvette are the body and the LS6. It is a tube frame, with Nascar Jerico tranny and nine inch rear end. Nascar Brembo's etc. Below is our team Camaro.....Howe chassis and Howe body, carbureted 383 LS6, 570 HP.

http://i641.photobucket.com/albums/uu132/bosco022/100_0528.jpg

http://i641.photobucket.com/albums/uu132/bosco022/BemcoCamaroDISSept26.jpg

So for a setup going into a street/race (HPDE, AutoX, road course....not competitive series) 02 Camaro (curb wt 3500ish), would a stock cube LS2 with 11.1-11.5 cr a mid 23x cam, FAST intake, and high quality cylinder head (using stock crank, forged rods/pistons) be adequate? Motor should make close to 600 fly wheel HP. My main concern is longevity. What lifters and rockers and pushrods (3/8?) would best fit this type of application?

Camaro99SS
06-19-2012, 09:04 PM
So is their any REAL need a forged crank on this type of motor...If you budget oriented what components are MUST have upgrades?


At the risk of stating the obvious here, one area I would be careful is how well the rotating assembly is balanced, particularly with extended high rpm use. The mfg's like Scat certainly offer this, usually within ~1gram. Places like Texas Speed or other specialty engine shops who do everything in house tend to get theirs within 1/2 gram or less. Alot of shops tend to farm this process out, so it can be difficult to actually tell how thoroughly this gets done. It may not be enough to make a difference, but every little bit counts, and I'd rather spend any extra $ here instead of a heavier forged crank since you won't be spraying or putting any big load on the engine.

Jason

Orange Juice
06-19-2012, 09:19 PM
Interesting reading, I just wanted to ask if the ls2 build is not economic then maybe a stroked ls1 would make a good track motor.

pharmd
06-19-2012, 09:57 PM
Interesting reading, I just wanted to ask if the ls2 build is not economic then maybe a stroked ls1 would make a good track motor.

The decision was between stock cube LS2 vs stroked LS2 (402). The question was really, is the extra power, especially the TQ, really necessary for this type of car. I'll be honest, I haven't been able to drive the car at many of these events yet, so I certainly need seat time, time to learn my car. My initial thought was an LS2 would make more than enough power for me to learn under. Then after a season or 2 of getting familiar, and making some tweaks here and there, then maybe I could build the big motor....if I wait a few years, I will do a sleeved LS2 427 with LS7 heads.

jbhotrod
06-20-2012, 09:20 AM
Depends on class rules. In the 1990's Oldsmobile was racing in a Road Course Series (ALMS, Pirelli Challenge, can't quite remember). The engine rules were not restricted for displacement. They ran BBC's in the 600+ CI range and did not spin the hell out of them. They swithced to an Aurora based engine near the end of the series. If you have a displacement limit, then you want as much bore as you can, within the confines of the block, at the expense of stroke. That way you can maximize the effectiviness of the displacment.

That's why Cup cars are around 4.185x3.25 or 4.25x3.15, been awhile since I looked into it.

How high were they spinning the old Can-Am Group 7 494ci engines to?

SSCamaro99_3
06-20-2012, 01:12 PM
How high were they spinning the old Can-Am Group 7 494ci engines to?

Apparently my recollection about the article on the Olds mid 90's cars was not correct as pointed out by garcr4. I can't find much on rpm limit on the Group 7 cars.

http://www.bruce-mclaren.com/the-cars/canam.html

http://www.camaros.org/copo

That may shed some light. Second article said ZL-1 427 was limited to 6750 rpm.

garcr4
06-20-2012, 02:50 PM
So for a setup going into a street/race (HPDE, AutoX, road course....not competitive series) 02 Camaro (curb wt 3500ish), would a stock cube LS2 with 11.1-11.5 cr a mid 23x cam, FAST intake, and high quality cylinder head (using stock crank, forged rods/pistons) be adequate? Motor should make close to 600 fly wheel HP. My main concern is longevity. What lifters and rockers and pushrods (3/8?) would best fit this type of application?

I'll take a stab at it and say the motor you are describing would make about 530- 550 flywheel HP. That is more than enough to motivate a well set up road racer.

I have found that suspension tuning, braking performance, tire & wheel combination, weight, TORQUE........and tightening up the nut behind the wheel are key for optimal road course performance.

pharmd
06-20-2012, 09:49 PM
I'll take a stab at it and say the motor you are describing would make about 530- 550 flywheel HP. That is more than enough to motivate a well set up road racer.

I have found that suspension tuning, braking performance, tire & wheel combination, weight, TORQUE........and tightening up the nut behind the wheel are key for optimal road course performance.

We are speculating closer to 600flywheel, my LS1 that just blew made 540fly wheel (460rwhp) and we are going to use a superior cylinder head and a touch bigger cam.

The nut behind the wheel is probably where the bulk of the problem lies...and that can't be improved until we have a running car again. So we are full speed ahead on the build.

How important are a high quality rocker (like T&D), limited travel lifters on something like this?

RAMPANT
06-20-2012, 10:06 PM
Great information guys.

Read through it all and it made me think of this.

https://wfapza.sn2.livefilestore.com/y1pp_wjQApeZymQEiLww7RqAwr0Y5Jcr98iVL2-VSR3_lu2SCxn0SbcI7hcdpGhuuLkZxs_jqRhqYf_GhIQF67Scy ffDsySNHli/532678_10150901597382358_1122910055_n.jpg

garcr4
06-21-2012, 07:51 AM
We are speculating closer to 600flywheel, my LS1 that just blew made 540fly wheel (460rwhp) and we are going to use a superior cylinder head and a touch bigger cam.

The nut behind the wheel is probably where the bulk of the problem lies...and that can't be improved until we have a running car again. So we are full speed ahead on the build.

How important are a high quality rocker (like T&D), limited travel lifters on something like this?

The Grand Am teams use Jesel and T&D Rockers for endurance applications, however I understand the Nascar K&N Series motors (carb LS2's with 243's) run stock rockers with the Comp Cams trunion upgrade. I think they twist those in the 7600 range.

I had T&D shaft rockers on the Vette and removed them due to clearance issues with my fabricated valve covers. Have gone back to stock with trunion upgrade and stock valve covers. Have not race it since, will report back.

jbhotrod
06-21-2012, 05:47 PM
I'll take a stab at it and say the motor you are describing would make about 530- 550 flywheel HP. That is more than enough to motivate a well set up road racer.

I have found that suspension tuning, braking performance, tire & wheel combination, weight, TORQUE........and tightening up the nut behind the wheel are key for optimal road course performance.

Thanks sscamaro.

Garcr4, do you know how high the Can-Am group 7 big block 494ci V8s revved to? And do you have any details on the C6.R Vettes racing in ALMS, Rolex, etc? How high did the old Trans-Am Boss 302s, Camaro D/Z 302s, etc rev to? If you know..

Thanks.

garcr4
06-21-2012, 08:19 PM
Thanks sscamaro.

Garcr4, do you know how high the Can-Am group 7 big block 494ci V8s revved to? And do you have any details on the C6.R Vettes racing in ALMS, Rolex, etc? How high did the old Trans-Am Boss 302s, Camaro D/Z 302s, etc rev to? If you know..

Thanks.

I don't know for sure, but I'll give an opinion:

The old Can Am Motors: 7200 area

C6R 7.0 liter: under 7000

Old TA cars: pushing 8000, no torque there, but they geared the hell out of them and ran em up.

pharmd
06-21-2012, 10:29 PM
I don't know for sure, but I'll give an opinion:

The old Can Am Motors: 7200 area

C6R 7.0 liter: under 7000

Old TA cars: pushing 8000, no torque there, but they geared the hell out of them and ran em up.

We are going to select a cam that will make power to 7k, but setting shift point at like 6500, with flexibility to run to 7500 if necessary. I hope to keep it under 6500 (for longevity purposes)...but when you are racing, sometimes the competitiveness takes over and you do stupid stuff. I think we will just stick with stockers + trunion upgrade, select a quality limited travel lifter and call it a day.

DaleTx
06-22-2012, 12:58 AM
I do not have experience with autocross but I do have experience driving and setting up my car and engine for running road courses (track days events). First, beef up the brake system... use the largest diameter rotors that will fit in your wheels. Get a good thick vented type rotors. Second, get your chassis set up so the car stays flat in the corners, is balanced, and is stable at high speeds. Make sure you have a good solid platform that will handle the horsepower safely.

As far as the engine goes.... I have found that an engine that has a smooth linear power with good power right off the bottom is good. When you roll on the throttle coming out of a corner you don't want the engine to bog or hit too hard. Also, a nice wide power band is good so you don't have to shift as much. I drive my car on a 2 mile road course with a chicane and a couple of straights (120mph+) and I can do the whole track using only two gears. High average torque and horsepower over the range that you will run is better than a high peak number. My current engine is a small block that puts out 450Hp and 450Trq with peak power at 6,500rpm. This combo was great for learning how to set up the car and how to drive.

Currently I am building a naturally aspirated 427CI LS2 with LS7 heads. This engine will put out high average torque and Hp from 3500 up to 7000 + rpm. The 450 Hp small block cost about 10K to build and the 427 LS engine with dry sump oil system will cost more than twice that. I would recommend to do a good solid 500 + horsepower engine to start out with and work on getting the brakes and chassis set up and then go for the big power when you wear that one out.

Thats my 2 cents... good luck with your project!

garcr4
06-22-2012, 06:38 AM
We are going to select a cam that will make power to 7k, but setting shift point at like 6500, with flexibility to run to 7500 if necessary. I hope to keep it under 6500 (for longevity purposes)...but when you are racing, sometimes the competitiveness takes over and you do stupid stuff. I think we will just stick with stockers + trunion upgrade, select a quality limited travel lifter and call it a day.

Just my .02, but I think you would be better off camming the motor for the actual intended range you plan to use. If you cam it to turn 7500 you are going to move the power band up in the range and lose some low end torque and power.

For road racing LS motors we try to cam for good power and torque from 3500-7000 max. Most of our motors seemed to only like about 6800 then they screamed "shift me". A couple of years ago when the Grand Am Rolex GT cars were using LS2's they were not even allowed the stock cam. They had to use a dummed down cam yet they still ran some amazing lap times equal to and some cases better than National type SCCA GT-1 cars with upwards of 800 HP.
The lesson I have learned is "Torque is King."

pharmd
06-22-2012, 07:41 AM
Just my .02, but I think you would be better off camming the motor for the actual intended range you plan to use. If you cam it to turn 7500 you are going to move the power band up in the range and lose some low end torque and power.

For road racing LS motors we try to cam for good power and torque from 3500-7000 max. Most of our motors seemed to only like about 6800 then they screamed "shift me". A couple of years ago when the Grand Am Rolex GT cars were using LS2's they were not even allowed the stock cam. They had to use a dummed down cam yet they still ran some amazing lap times equal to and some cases better than National type SCCA GT-1 cars with upwards of 800 HP.
The lesson I have learned is "Torque is King."

We were thinking like your suggesting. My last cam (LSL lobed 231/239 113lsa) had nice average power and a great TQ curve for a stock cube LS1, while it didn't peak really past 7k, it did carry the power pretty well, and this is to which I am referring. I just want it NOT to fall on its face passed that RPM range...in the event I'm needing to hold a gear (vs taking the time to shift in the situation where you are coming upon a turn or curve or a stop). I have seen several folks have to hold gears on autox because it just didn't make time sense to shift. This is the setting where having the extra RPM I think could give you some seconds.

The "Torque is King"...its that also a balance with traction. TQ applied is great, as long as you can put it down, if you over power the rear tires constantly on coming out of low speed turns, how useful is it? That is where we are. Somewhat limited by the minimum 200 treadwear rule, along with the fact that a 315 is really as big as I can go on the rear...I can imagine I will be needing to modulate throttle input quite a bit with even my stock cube LS2. But we will certainly select a cam that makes great "AVERAGE" power from 3500-6500, as this will be the sweet spot in terms of power production.

Here is my final LS1 dyno's, the lower curve was with Performance Induction 215's, the higher curve was Advanced Induction 5.3 heads (same cam, intake, compression etc)

http://i139.photobucket.com/albums/q316/05pharmd/BW02SS_PI215_vs_Ai218GMLS53.jpg

garcr4
06-22-2012, 09:22 AM
That DOT treadwear rule of 200 is a killer. The Corvette has the Continental/Hoosier 325 in the rear and with less than 500 FWHP and 430 or so torque we have plenty of forward bite.

pharmd
06-22-2012, 12:51 PM
So it looks like I'm only looking at about another $1000 to build a 408 vs the 366. Seems kinda silly to leave that type of power difference on the table if we are only talking 1K difference.

What do you guys think? Based on my calculations the 366 would make around 485rwhp/439rwtq whereas the 408 would make 540rwhp/488rwtq.

Those are pretty big differences for just 1k. Plus I could run a less aggressive cam, so we potentially have more longevity with this setup due to being not as hard on valvetrain parts.

I am all for "learning to drive" with a nearly stock hp level car, then as you progress as a driver moving up to something that makes better power. But in this situation, the cost to remove/rebuild the stock cube LS2 after a couple years, to move to the 408, just seems like a waste. It would be way more costly to R&R that vs the 1K difference to build the 408 to begin with.

Am I stupid for looking at it this way?

garcr4
06-22-2012, 01:32 PM
So it looks like I'm only looking at about another $1000 to build a 408 vs the 366. Seems kinda silly to leave that type of power difference on the table if we are only talking 1K difference.

What do you guys think? Based on my calculations the 366 would make around 485rwhp/439rwtq whereas the 408 would make 540rwhp/488rwtq.

Those are pretty big differences for just 1k. Plus I could run a less aggressive cam, so we potentially have more longevity with this setup due to being not as hard on valvetrain parts.

I am all for "learning to drive" with a nearly stock hp level car, then as you progress as a driver moving up to something that makes better power. But in this situation, the cost to remove/rebuild the stock cube LS2 after a couple years, to move to the 408, just seems like a waste. It would be way more costly to R&R that vs the 1K difference to build the 408 to begin with.

Am I stupid for looking at it this way?

I would probably do the same thing with cost as a factor. I wish we would have built a 408 instead of a 383 for the Camaro. But it makes 570 FWHP anyway, not too shabby. I went from racing a 250 HP SCCA EP/GT2 240 Z to a 500 HP GTA stock car. My first race was at Daytona and it was a little spooky the first time out hitting 180 in the trioval. However, my second race was at Palm Beach then Moroso) and I won over about 20 some stock cars in the Crane Cams V8 StockCar Series.

pharmd
06-26-2012, 07:25 AM
A little update...going LS2 based 408, dragonslayer crank, scat ultralight rods, Mahle pistons, ACL race bearings. Will top it off with Advanced Induction TFS heads, Custom cam, FAST 102 Intake/TB, ARH 1 7/8" headers, ORY, 4" DMH cutout. I am hoping we will be in the neighborhood of 500rwhp, but the dyno I use is considered "the heartbreaker", so IDK.

garcr4
06-26-2012, 03:10 PM
A little update...going LS2 based 408, dragonslayer crank, scat ultralight rods, Mahle pistons, ACL race bearings. Will top it off with Advanced Induction TFS heads, Custom cam, FAST 102 Intake/TB, ARH 1 7/8" headers, ORY, 4" DMH cutout. I am hoping we will be in the neighborhood of 500rwhp, but the dyno I use is considered "the heartbreaker", so IDK.

Sounds like 600 plus at the flywheel, I think you will make your target.

pharmd
06-26-2012, 04:22 PM
Sounds like 600 plus at the flywheel, I think you will make your target.

Yes, I am hoping 600ish flywheel, anything over that is just icing on the cake. Putting the power down, and dialing in suspension will be the hard part (and of course learning how to drive!)

Fb0dy0nly
07-15-2012, 12:19 PM
The only things there that are Corvette are the body and the LS6. It is a tube frame, with Nascar Jerico tranny and nine inch rear end. Nascar Brembo's etc. Below is our team Camaro.....Howe chassis and Howe body, carbureted 383 LS6, 570 HP.

Sorry for the thread hijack OP but what is the reason for using a carb as oppose to the stock EFI that comes on these motors? Do you have to run carb or is that a choice for tuning the power output on these road setups?

pharmd
07-15-2012, 12:27 PM
Sorry for the thread hijack OP but what is the reason for using a carb as oppose to the stock EFI that comes on these motors? Do you have to run carb or is that a choice for tuning the power output on these road setups?

Carbs make more power, and you can probably run a larger cam along with a Carb intake
Which makes more high rpm power.

FASTFATBOY
07-15-2012, 07:55 PM
Geebus, some of the shit you see posted on the internet puked up by someone who read it somewhere.

RPM KILLS engines. The end.

In a autox or HPDE car you want tabletop flat TORQUE.

Most autox events in our cars should be run in 2nd gear.

I built a stock LS6 for my car to HPDE with, it works very very good. Makes 385 to the wheels and about the same in tq.

The reason you see cars on TV in races spinning the engine to the moon is because they have cubic inch limits or restrictors or both.

Listen to an ALMS GT2 C6 go around the track compared to all the others, sounds like a pulpwood truck.

IMO The LS1 has better oiling and is less likely to kill the bottom end in long sustained left handers.

Improved Racing makes a baffle that bolts into our stock pans to help with lateral G oil starvation, this issue really only shows its head when you get on good rubber(less than 200 treadwear) and really learn to push it.

If you think you need a 9000 rpm engine to go fast on a roadcourse you are mistaken, here is a vid of me at Roebling Road in Ga, never shifted the car out of 4th gear. I did this to teach myself momentum and corner entry speed. Passed damn near everyone in my run group that weekend with the exception of a Nissan GTR, Porsche 911 racecar and a BMW Z3 on race rubber with a damn good driver.

My car ran 137 MPH at the end of the front stretch and weighs 4000 lbs with instructor in the car.


This was my first weekend at this track.
http://youtu.be/qCNDermGiwg

FASTFATBOY
07-15-2012, 08:30 PM
So it looks like I'm only looking at about another $1000 to build a 408 vs the 366. Seems kinda silly to leave that type of power difference on the table if we are only talking 1K difference.

What do you guys think? Based on my calculations the 366 would make around 485rwhp/439rwtq whereas the 408 would make 540rwhp/488rwtq.

Those are pretty big differences for just 1k. Plus I could run a less aggressive cam, so we potentially have more longevity with this setup due to being not as hard on valvetrain parts.

I am all for "learning to drive" with a nearly stock hp level car, then as you progress as a driver moving up to something that makes better power. But in this situation, the cost to remove/rebuild the stock cube LS2 after a couple years, to move to the 408, just seems like a waste. It would be way more costly to R&R that vs the 1K difference to build the 408 to begin with.

Am I stupid for looking at it this way?


The drag racer mentality is STRONG in this one.

Save the $1000 and buy you some brakes, ducting, and sheet metal spindle ducts from Blaine Fabrication.

Watch this vid, and understand WHY 540 to the wheels won't help you. The only thing a lot of power teaches you is to WAIT on the next straight to play catch up and set your brakes on fire.

This is at NOLA Motorsports Park in La, my first time at this track. This track is VERY slick. Pay particular attention from 9:55 on, thats when school starts.

At the end of day 2 I could pass the Miata, but was still very very close.

http://youtu.be/q0qkpqNwLvM

pharmd
07-15-2012, 08:56 PM
Geebus, some of the shit you see posted on the internet puked up by someone who read it somewhere.

RPM KILLS engines. The end.

In a autox or HPDE car you want tabletop flat TORQUE.

Most autox events in our cars should be run in 2nd gear.

I built a stock LS6 for my car to HPDE with, it works very very good. Makes 385 to the wheels and about the same in tq.

The reason you see cars on TV in races spinning the engine to the moon is because they have cubic inch limits or restrictors or both.

Listen to an ALMS GT2 C6 go around the track compared to all the others, sounds like a pulpwood truck.

IMO The LS1 has better oiling and is less likely to kill the bottom end in long sustained left handers.

Improved Racing makes a baffle that bolts into our stock pans to help with lateral G oil starvation, this issue really only shows its head when you get on good rubber(less than 200 treadwear) and really learn to push it.

If you think you need a 9000 rpm engine to go fast on a roadcourse you are mistaken, here is a vid of me at Roebling Road in Ga, never shifted the car out of 4th gear. I did this to teach myself momentum and corner entry speed. Passed damn near everyone in my run group that weekend with the exception of a Nissan GTR, Porsche 911 racecar and a BMW Z3 on race rubber with a damn good driver.


This was my first weekend at this track.
http://youtu.be/qCNDermGiwg

How did you like the NT05's?

FWIW, my motor we are building is going to peak around 6300, I plan on using the IR baffle, and potentially an accusump to control oil, the use of LS2 was because that is what we had available (spare LS2 block from spun rod bearing in TBSS). While more HP is certainly not needed on autox, since I was going to have to build a motor I opted to go a little bigger (408ci), and have a broader powerband (so I wouldn't have to lean on it as much to make power). I'm sure it will be way more power that I need for my limited driving skills, but hopefully I can "grow" into the power with practice. On the bigger courses during HPDE/road course events, the power of the 408 should be useful.

pharmd
07-15-2012, 09:07 PM
The drag racer mentality is STRONG in this one.

Ouch. Lets keep the comments on track. I have an extra grand to put towards the build, AND still have aftermarket brakes, blain fab ducts etc. This car is NOT going to be just a track car. It will see significant street duty as well. I don't drag race. I feel like my rationale is justified in doing the bigger motor. Cost/benefit favors it. To say that more power is harmful may be true in my hands, but a properly setup car in hands of someone who CAN drive wins. Sure tight courses it won't reallly help, and could actually be a detriment on Autox, but its the decision I'm sticking with.

How did you like the NT05's in your application?

FASTFATBOY
07-15-2012, 09:42 PM
Ouch. Lets keep the comments on track. I have an extra grand to put towards the build, AND still have aftermarket brakes, blain fab ducts etc. This car is NOT going to be just a track car. It will see significant street duty as well. I don't drag race. I feel like my rationale is justified in doing the bigger motor. Cost/benefit favors it. To say that more power is harmful may be true in my hands, but a properly setup car in hands of someone who CAN drive wins. Sure tight courses it won't reallly help, and could actually be a detriment on Autox, but its the decision I'm sticking with.

How did you like the NT05's in your application?


I can tell you this, the guy in the second video that passed me on the first lap in the black F body had a head cam deal that made 460rwhp and weighed 3300 ready to race.

His power to weight will be similar to yours EXCEPT, your brakes are gonna FRY with that much power. His C6 Brakes with ducts and hoses would KILL brake pads, a $250 set of fronts would do good to last 1 or 1.5 events. With that said, put 18 inch wheels on and buy the biggest brakes that will fit inside them.

He drove my car the last session of the day, went home and took his engine apart to make it a LS6 like I have, he saw the light. Instead of buying 18 inch wheels and the more expensive tires to go with them JUST to put bigger brakes on the car he decided to pull some power out of it and DRIVE the car better.

IMO the NT-05 is THE best tire for the money out there, grip is good and they last very well on track.

A word of advice, don't get on sticky tires for a while, stay on cheap street tires for at least 4-5 trackday events(8-10 days) before even moving up to a NT-05.


HPDE is not racing, it's learning how to drive and do it well. The F Body platform can be setup to handle very well, the weight is the killer.

crainholio
07-16-2012, 06:37 AM
HPDE is not racing, it's learning how to drive and do it well. The F Body platform can be setup to handle very well, the weight is the killer.

Still can't believe you posted a video of a Miata smoking you. And on a straight no less.

If Miatas are anything more than a rolling chicane, you don't give advice. :eyes:

FASTFATBOY
07-16-2012, 08:09 AM
Still can't believe you posted a video of a Miata smoking you. And on a straight no less.

If Miatas are anything more than a rolling chicane, you don't give advice. :eyes:

Get out on the track with a Spec Miata and try and keep up LMAO. Many a "bad ass"car has had their asses waxed by a well driven Spec Miata.

The last set of corners at NOLA I couldn't figure out, he pulled out a lot of ground in that section.

To put that into perspective, my car runs 115mph in the 1/4 mile. Spec Miata's make maybe 150 rwhp.

Again, the typical drag racer mentality. Road course racing is about grip and corner speed. I was trying to point out with my 385 rwhp car with a lot of suspension and a decent driver has a hard time dealing with a 4 cylinder car on slicks. It's all about momentum and learning how to keep it, not about having a lot of power to go fast.


Do you road course race?

EDIT

I just realized you are the OP.

You are in for a RUDE awakening when you get on track with all that power and you have to point a Spec Miata by and watch him LEAVE you, all of the things I said will come into clarity.

Most all of us who came from the drag racing world have this kick in the nuts happen early on.

Drag racing 90% car, 10% driver.

Road racing 30% car, 70% driver.


And just so you don't think I am a no driving NERD.

I did the Hot Rod Power Tour Long Haul this year on street tires and cheap brake pads.

At the Muskegon autocross I finished 11th out of 68 cars.

I also did the Optima Batteries Ultimate Street Car Faceoff at the end of the Power Tour. Also on 300 treadwear street tires, but I had my Carbotech Pads but no brake ducts. I put the Carbotechs on in the hotel parking lot the night before Eagles Canyon Road Course.

Here is where I finished, Car 36 David Driver A Lambo Gallardo was only .2 quicker in the autox and 2 seconds faster on the road course at Eagles Canyon

http://www.optimainvitational.com/Faceoff%20at%20HRPT%20Results.pdf

SO take what I am trying to help you with and do what ya want with it. Just trying to steer you down a road I already been down.

427
07-16-2012, 10:11 AM
I would build the more powerful engine now, you can easily tune it down if you want. If you build the low power engine, it will always be low power unless you take it apart. Some people I know run second gear in auto cross events to calm the engines power, you could also restrict the intake very quickly in this type of car.

Kurt

crainholio
07-16-2012, 05:23 PM
I'm not the OP.

I've been doing HPDEs and Time Trials since 2000. Three 1st place and a 2nd place trophy for my class in TT. Bondurant 3-day school in 2004. I still learn something new pretty much every time I hit a course, so I've got more improvement to make. No wheel-to-wheel competition and no plans to go there.

Haven't been on a drag strip since 2000, and I agree w/ your points about the transition from drag to road course. Been there done that. I brought the car home from Pocono in July 2000, swapped out the auto trans for a T56, and never looked back. :)

Spec Miatas stopped being a problem (other than waiting for a point-by to pass them) after 2004 and an upgrade to slicks. ;)


Get out on the track with a Spec Miata and try and keep up LMAO. Many a "bad ass"car has had their asses waxed by a well driven Spec Miata.

Do you road course race?

EDIT

I just realized you are the OP.

You are in for a RUDE awakening when you get on track with all that power and you have to point a Spec Miata by and watch him LEAVE you, all of the things I said will come into clarity.

Most all of us who came from the drag racing world have this kick in the nuts happen early on.

FASTFATBOY
07-16-2012, 07:20 PM
I'm not the OP.

I've been doing HPDEs and Time Trials since 2000. Three 1st place and a 2nd place trophy for my class in TT. Bondurant 3-day school in 2004. I still learn something new pretty much every time I hit a course, so I've got more improvement to make. No wheel-to-wheel competition and no plans to go there.

Haven't been on a drag strip since 2000, and I agree w/ your points about the transition from drag to road course. Been there done that. I brought the car home from Pocono in July 2000, swapped out the auto trans for a T56, and never looked back. :)

Spec Miatas stopped being a problem (other than waiting for a point-by to pass them) after 2004 and an upgrade to slicks. ;)

Your cracking on me keeping up with the Miata on STREET TIRES and your on slicks????? The Miata I was chasing was on slicks, it was a racecar. I'm in a 4000 lb barge with A/C that I did the Power Tour long haul in.

It was my first time at that track LOL.

Slicks are worth 4-5 seconds at least over street tires, probably more than that..... the NT-05 arent slicks by any stretch.

I will probably never get on slicks, NT-01 or RA1 or R888 is as close as I will get. I have another year or two on these tires till I move up in grip, I have a lot to learn on these tires. I am not ready to run slicks and won't be for a good long time.

pharmd
07-16-2012, 10:20 PM
I would build the more powerful engine now, you can easily tune it down if you want. If you build the low power engine, it will always be low power unless you take it apart. Some people I know run second gear in auto cross events to calm the engines power, you could also restrict the intake very quickly in this type of car.

Kurt

Agreed. I cant justify trying to save $1000 and leave 50-70 ft lb on the table. A broad flat TQ curve HAS to be helpful when coming out of corners. The expense and time it would take to swap to a more expensive motor just doesn't make sense.

93Polo
07-18-2012, 08:41 PM
Geebus, some of the shit you see posted on the internet puked up by someone who read it somewhere.

RPM KILLS engines. The end.

In a autox or HPDE car you want tabletop flat TORQUE.

Most autox events in our cars should be run in 2nd gear.

I built a stock LS6 for my car to HPDE with, it works very very good. Makes 385 to the wheels and about the same in tq.

The reason you see cars on TV in races spinning the engine to the moon is because they have cubic inch limits or restrictors or both.

Listen to an ALMS GT2 C6 go around the track compared to all the others, sounds like a pulpwood truck.

IMO The LS1 has better oiling and is less likely to kill the bottom end in long sustained left handers.

Improved Racing makes a baffle that bolts into our stock pans to help with lateral G oil starvation, this issue really only shows its head when you get on good rubber(less than 200 treadwear) and really learn to push it.

If you think you need a 9000 rpm engine to go fast on a roadcourse you are mistaken, here is a vid of me at Roebling Road in Ga, never shifted the car out of 4th gear. I did this to teach myself momentum and corner entry speed. Passed damn near everyone in my run group that weekend with the exception of a Nissan GTR, Porsche 911 racecar and a BMW Z3 on race rubber with a damn good driver.

My car ran 137 MPH at the end of the front stretch and weighs 4000 lbs with instructor in the car.



Alot of truth above. I agree with building a strong mid range. Also I would not go with very aggressive lobes.


However, one reason the C6.R especially the old 7.0 GT1 cars run such low RPM is they have restrictors on the air intake. Like the high rpm motors they are running what the rules give them.

NEVRLIFT
07-18-2012, 11:01 PM
Just go with the big cube motor. For $1000, that's well worth the money. Just put a medium sized cam in it that is specialized for mid range torque.

I've used NT05s at a few track events and they are great but can get greasy when in extended sessions. That's where the Hoosiers shine. With 500+whp, not sure how long you'll want to stick with street tires.