Sup. I have a couple of questions. If I wanted to build a road race LS1, what exactly am I shooting for in a Road Race Engine? Horsepower, Torque, Large Powerband or something diffrent? Thanks for the responses in advance.

 

All of they above + reliability.
427 N/A ls1 11:1 comp. 500rw
will run all day, every day.
I think the 7.0 L. vett’s are undefeated this year
on the road courses.

 

with my setup i plan on road racing. its a high compression, forged 347, heads, custom cam spec'd toward my power range, ect. i plan to dry sump it as well. you'll need a valvetrain capable of withstanding the sustain abuse the road course will put on your enginee. if you plan to road race you have to think beyond just "power"; brakes, tires, and suspension are all key. i suggest you research in the autocross/road racing forum and see what kind of setups the guys who are actually doing it run.

 

You will need the whole car set up (suspension, brakes, etc., etc.)

As for a motor -- basically over build everything! They make some really good products for LS1s now that will help in the long run.
Number one on my list is the oil squirter valve covers -- www.drysump.com (mods -- I know they aren't a sponsor so remove if inappropriate). I know Kurt at wheel to wheel has been using these.

Get the best parts you can buy -- Sonny Bryant crank, Carrilo rods, etc. and if you keep the power reasonable it will last forever.

 

Like jrp said, go to the autocross forum. They are always talking about tranny & dif coolers, dry sumps, roll cages, tires, hym-joint suspension parts......yes you need a motor that can take it (500rwhp to run 150mph sustained etc), but if you want to be competitive, there is a LOT of stuff you'll need to do to the rest of the car. I know. I've set my car up for drag racing & I've come to find out most of it will need to be redone for ORR, or it will limit what class I run in. SIGH!

 

All of them no matter what engine you run.

Seriously, what kind of events are you planning on? Spec classes (AI, CMC) will limit your modifications.

If your road race LS1 is traveling around the track in a 4th f-body, I wouldn't even bother with the engine until you improve everything else starting with safety equipment and suspension. The engine is NOT the weak point in an f-body. 500 HP wont help **** get through a 30 mph turn.

If your ready for the engine work, build it to spin at 7500 RPMs but set you limiter to 6300. Be concerned with heat and lubrication.

 

Not too familiar with the regs you will be working with but the weight of the car will have a bearing on where you want the power band of the engine to be. The lighter you can get away with, the more revvy you can make the engine and not get bogged down at the lower end. If you are restricting the performance by having a heavy car you will need strong torque at the low end.

 

All the above is good advice. Like any other kind of racing, money dictates how fast you can go in road racing. The suspension and brakes must be in good order or you will be dead last, or a track hazard. Good shocks, sway bars, and alignment are required along with stainless flex brake lines and racing pads and flush the system with high temp fluid. Add a good oil cooler, and trans cooler. That's what I did this year with my 99 C5. Now to the fun part,,,the motor;; plan to keep the RPM down, (RPM=$$) (RPM=valve spring life) endurance is critical. Buy the best components that you can afford (e.g. shaft rockers, hardend pushrods) make the valvetrain bullet proof. Sacrafice peak power benefits for endurance (forget the ultralight rods). You need good torque to get out of the corners, but you will spend a lot of time at WOT, so max HP is good too. A road race motor has to do it all, and last about 15 hours per year. Endurance is critical.
I'm building a 346 12:1 with a 237/242 .595 cam
for SCCA 25 minute races. Accusump, yes! I have spent way too much money on dry sump systems. They are great, but major $$ I could buy a spare short block for the cost of all of those oil lines.
Good Luck, Racecar

 

Where do you plan on racing? I know there are a lot of nice tracks out there in California. If I had the money I would get into some road racing. It seems like a lot of fun, but just to race at the Barber's Motorsport track here costs an arm and a leg...for me anyways...

 

Thanks. You guys are totally knoledgable. I didn't know the whole thing on wheight, s thanks. I knew that the engine had to be endurent, and I know the rest of the car has to be set up first. It's the engine that i'm concearned with now. But thanks. I got alot of perspective and a little slap of reality thanks!

 

Go for it Dude,
I drag raced many years ago, it is a blast to pop the clutch with some big HP and feel the G forces pin you to the seat. The cool thing about road racing is at the 1/4 mile post you keep your foot in it all the way to the end of the track, then slam on the brakes and turn into a corner and keep going, all this with another car beside you, and several behind you. Keep going for 25 minutes. As you can probably tell, I'm hooked. Can't wait for next year to get out there with a new motor, and show those 911 and 944turbo cars my tail lights. Let's rock!!

 

Where is Louis when you need him?

I do ORR in my car along with a fw lapping days every year. The biggest thing you need to ask yourself before you do anything is, "How far do I want to take this car?"

A reletively stock Fbody with some spring/shock changes and a pad compound change can do pretty good around the track if you dont plan on pushing it 10/10.

building a car that makes a ton of power and then taking it to a lap day without alot of experience can bite you in the ***, big time. Trust me, been there, done that, almost **** myself in my fire suit.

 

If I was gonna do some ORR, the only mods Id do to the engine is headers and the asa cam. Then concentrate on the brakes, handling and some weight reduction. Id love to try those nittos II tires 275s on some 17" rims. Probably handle like its on rails.

 

Big brakes are worthless in ORR (ok not completely). Just lift off the throttle and you will slow enough for the corners. most of the corners I was bale to cook through at or close to 150mph at the PE130. there was only 1 combo where I could have used then but just threw it down a gear instead. You want good ssuspension and tires for ORR. Many stock interiored cars with the addition of a 4pt cage run with a 168mph tech speed.

 

Horsepower sells motors ... torque wins races.

Give me 400ft/lbs at 4000 rpm and I will dog you off the corners all season long ...

 

As a suggestion, before you start modding your car, try to determine what event you'll be driving in. There's a full spectrum of "road racing" type venues out there which are all rule and specification driven. What and how you modify your car will depend on the type of event, club, and sanctioning body you'll be driving in. There's everything from autocrossing which requires very little modifications; high performance driving events & driving schools which require primarily safety and reliability mods: high speed time trials & open road challenges where you'll start to extensively modify just about everything; to finally spec, club,and cup racing where you're driving production "race-type cars" to ultimately the full blown American LeMan's Series (ALMS) where cars like the C5R rule.

Mods for production cars are usually done in this order:

1. Brakes (rotors, pads, lines, fluids, proportioning valves, fluid, calipers, pistons)

2. Suspension (sway bars, bushings, heim joints, shocks, springs, bushings, ride height, alignment, corner balancing)

3. Safety equipment (spec roll bar or cage, 3" 5 point harness, FIA seats, 10# halon system with engine, cockpit, gas tank/fuel cell distribution, electrical kill switch, fuel cell (depending on regs),airbag removal, new steering wheel, plus personal safety equipment (Snell 95 full face helmet, nomex suit & underwear, shoes, gloves, neck brace or Hans device) window net or arm restraints

4. Car reliability upgrades- Accusump, high capacity radiator with integral oil cooler, diff/trans coolers, high capacity oil pump, thermal protection, high temp synthetics, bullet proof (Rockland Standard) tranny's, high grade clutch.

5. Optimized powerplants with power range and gearing configured to give you a linear power curve from the slowest exit speed coming out of the slowest/tightest curve on the track you are driving on. Trans and diff will provide ideally a smooth power curve with the fewest shifts necessary. Unlike drag racing, powerband is different with super high rpm-high horsepower curves not universally seen in road racing.

Easy-hell no. Expensive-absolutely. This is one reason most teams have some many cars. NASCAR (which road races in addition to other things) typically utilizes 15 or more cars and countless set ups and engines. Ironically, the best value from a price and factory support set up for the ALMS are probably from Porsche Motorsports with the full blown dedicated racecars, the GT series of the Carrera which sell at only $197,000 with the motors at a deal at only $54,000)

Lastly go to driving school, you can figure out what you like and learn to drive without killing yourself. Most clubs, sancitioning bodies and events require some "license" from a known driving institution.

Good luck and see you at the track. In my next life, I wanna be a C5R.

 

Especially the valvetrain. I would stay a little conservative on the cam duration and lift, smaller cams generally make more tq and better spring life.

How much power do you want? What track? How much $$? Any class or just track events?

One of the standard 224 112LSA cams would make a nice road race/track event cam for a stock short block car. I would also be very tempted to try a 224/224 110LSA 106 ICL, if you are willing to try a more radical cam, tried by a forum member about a year back. The tq curve was very strong.

 

IMO if you're new to RR or ORR then forget all about the engine. Any stock LS1 is more than fast enough to wipe the track with most of the cars that you'll see there. You might want to do some durability mods like coolers etc, but more hp should be the last thing on your list. Suspension/brakes/seat time, in no particular order are where you should spend your time/efforts. They'll pay you back with much larger dividends than hp will at this point.