LS road race/autox Motor choices
#21
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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.
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.
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.
#22
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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.
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.
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"
#24
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That's why Cup cars are around 4.185x3.25 or 4.25x3.15, been awhile since I looked into it.
#25
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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.
That's why Cup cars are around 4.125x3.25 or 4.25x3.15, been awhile since I looked into it.
#26
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 $$$ and the EPA being involved so the 4-strokes were given way to much displacement advantage. In reality it shouldve been 125 2-stroke vs ~185-200cc 4-strokes and 250cc 2-strokes vs ~330cc 4-strokes. Anyway the reason the 4-strokes took over is due to the power curve. Early on the 2-strokes were making MORE peak power than the 4-strokes but the power curve of them makes it much easier to ride faster. You can be in a gear too high and it dont matter while with a 2St if youre a gear too high it falls on its face and youll likely case the next jump and bust your *****. Same thing happened in MotoGP with the 500s vs 990s.
I realize a 2-stroke is a much more exagerrated example though as if youre not at the right rpm you arent going anywhere. But, I figured it may translate just a little bit to what yall are saying. Sorry for the essay but I just wanted to see if my insight may help a bit to people who dont understand...
But anyway FWIW I remember reading something about the Dodge Vipers being limited to 5000rpm or something like that for Le Mans but they still did well and I know this is a crappy source so dont flame me but on Forza the Viper race cars were limited to 6000rpm or less I wanna say.
And I know its not road racing but the tracks are similar as far as turns/straights, I raced motocross for half my life and always have been/will be a die hard 2-stroke lover but the 4-strokes have taken. Excluding my opinion that they were favored by the manufacturers to take over due to more $$$ 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 *****. 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...
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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?
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?
#28
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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?
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?
#29
Your real-world experience and knowledge is greatly appreciated by all.
#31
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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.
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.
Last edited by garcr4; 06-16-2012 at 08:49 AM.
#32
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Are you with the GARC guys out of Alabama?
#33
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.
#34
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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.
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.
#35
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.
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.
#36
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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.
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.
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Jason
Last edited by Camaro99SS; 06-19-2012 at 09:16 PM.
#39
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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.
#40
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.
That's why Cup cars are around 4.185x3.25 or 4.25x3.15, been awhile since I looked into it.