Road Course Racing car set up info

[Shoman594]

Hey guys, I had the idea of putting together all the great info on how to set up an SHO track car in one thread.

We could first talk about building a SHO track car and what could be installed

Exterior:

Tires
Brakes
Springs
Struts
Strut Tower Brace
Front and Rear sway bar sizes
Adjustable End Links
Control Arms
Alignment & Camber Plates

Interior:

Gauges
Roll bar or cage
Racing seats
Seat belts
Fire Systems
Helmet
Driving Suit, Gloves, Shoes
Video Camera
Lap Time Recorder


Setups for Different tracks?
Every track is different and i know some guys set up the car specifically for each track.

SHO specific information racing info?

Just a few ideas to bounce around, let me know what you guys think.

 

[drivinhard]

For the SHO, Brakes, Quaife and R comp tires. The rest is details

With street springs/struts (eibachs/tokicos) I (eventually, after trying everything) ran a 20mm/26mm bar set up and at the end of the day, it proved to be fastest. The front end takes a smidge longer to take a set on turn in, and feels weak knee'd if you've become used to a stiffer front bar, but it's quicker, and mid corner and corner exit grip is most excellent.

With coilovers/custom spring rates, the sway bar thing isn't as applicable, you just have to play around with it. Eric TT champ can chime in here.

I found working on the area's that the car was already strong in, proved to be more effective than working on the car's weak area's. Some of it's weak area's are just part of the design of the car, and not much you can do about it. The cars can be really, really good on corner exit, especially high speed stuff. There are some corners on some tracks where my Z06 is slower, you just can't be as aggressive as you could with the SHO. I would bet $1000 both of my SHO's were faster through the bottom of the esses at Road Atlanta, through and out of turn 5. And not only that, you could run it with one hand keeping your iced tea steady. In the Z06, you can't fit a needle up your sphincter running 10/10ths in the same spot. I have in car video from both, I could probably do timing splits and figure which is faster in that spot.

SHO track car Pro's:

-engine is virtually 100% dead reliable in n/a form
- Doesn't have the "I can't wad it up" scare factor. This is worth 4-5 secs lap
- The whole is greater than the sum of it's parts and numbers on paper.
- Simply the easiest car on the planet to drive 10/10ths.
- Excellent (potential) corner exit speed and balance. You can be 110% aggressive with it (on the uphill at Limerock, esses and T5 at Road Atlanta, T5/6 at blackhawk, etc). This is more fun (and faster) than running a car with 2x the power @ 90% in the same spot.

Con's

- a little down on all out power by 2009 standards
- nose heavy, eats front tires alive, doesn't rotate well on slow speed tight stuff
- wheel selection ain't great, although with the PR offerings it's better than it used to be
- could use more tire/wheel

 

[thebigjimsho]

^^^What he said.^^^

 

[Jonny Cash]

I would bet $1000 both of my SHO's were faster through the bottom of the esses at Road Atlanta, through and out of turn 5. And not only that, you could run it with one hand keeping your iced tea steady.

Thats funny you say that. The other day I was watching the Ferrari challenge @ RA, pouring rain. Every single one of them ended up in the grass on that turn. :laugh_ti:

 

[SHOspazz92]

Exterior:

Tires
Hoosier R6's if you want to be Competitive. If you want to run a street tire, I'd suggest something like a Dunlop Direzza Star Spec Z1.
Brakes
Cobra Brakes work great, However I liked Bob's idea with my car, The Willwoods he installed should be good for a full weekend with out worry of Fade or cracked rotors. Willwood FSL's FTW (TCE carries them).
Springs
Struts
Ground Controls all the way.
Strut Tower Brace
I've only had cars that have had them in the rear. My 95 had a real nice one in the rear. I thought installing one in the front would be more beneficial, However in opinion, The Turn in was not as sharp with one in there. One in the rear is fine.
Front and Rear sway bar sizes
I've only driven a cars with a Small front sway bar and Big rear. Current setup is a 20/26. It makes the car pretty loose and in my opinion thats how SHO's need to be to get around the real tight stuff, At least that's what I've found with Auto-X.
Adjustable End Links
I have no clue.
Control Arms
Anything adjustable for the rear is needed.
Alignment & Camber Plates
I'm learning

Interior:

Gauges
Oil Pressure, Oil Temp, Trans Temp.
Roll bar or cage
4 Point should suffice if all your doing is HPDE's, No need for the extra weight.
Racing seats
The lightest and most comfortable thing you can get, But then again this isnt your daily, So the lightest!

Seat belts
5 points anchored down properly!
Fire Systems
At LEAST something near the area of the power steering pump.
Helmet
Depends on the sanctioning body, But no reason to skimp on safety.
Driving Suit, Gloves, Shoes
No Clue.
Video Camera
Working on that.
Lap Time Recorder

Data Toyz has a nice setup.

So that's what I know (And that's not much). I've mainly been Auto-X'ing this car built for the road course. It's very interesting. Most the cars beating me are cars I know I could waste on the road course however I'm getting faster. I will say this, Auto-X puts some insane stresses on the car. There's a part of my cage (It's actually the welded in rear strut tower bar) where the welds are breaking! It certainly wasn't like that when I got the car! And I thought Auto-X was supposed to be cheaper!

-Sam

 

[NJSHO]

- Doesn't have the "I can't wad it up" scare factor. This is worth 4-5 secs lap

Other than lack of driver experience, Im pretty sure that is responsible for most of my passing of porches, bmw's, ect...

Before putting anything in the car, probably a good idea to remove as much weight as possible, then pretty much what drivinhard said.

 

[RonPorter]

I never had a strut tower brace, so I can't comment.

But, across four SHOs that I had on the track, one had the full-length "subframe connectors" welded in, and that care definitely had a better response.

I also had a variety of sway bar sizes across the cars, and I personally could get the car to react with all of the combos. IMHO, it's just what you perfer.

I agree with the "less weight" comment. After running a few diferent rim widths on the LGT, I would definitely find a way to get wider (7" - 8") rims on a SHO if I had another one for the track.

Oh, and breaking the welds and getting a good alignment is very key. Dial in as much negative camber as you can. On my SHOs, I ran -1.5 all the time, and, with regular tire rotations, had no wear issues. For a track-only car with track tires, I suspect that -2 to -3 would work better.

 

[SHOspazz92]

I never had a strut tower brace, so I can't comment.

But, across four SHOs that I had on the track, one had the full-length "subframe connectors" welded in, and that care definitely had a better response.

I also had a variety of sway bar sizes across the cars, and I personally could get the car to react with all of the combos. IMHO, it's just what you perfer.

I agree with the "less weight" comment. After running a few diferent rim widths on the LGT, I would definitely find a way to get wider (7" - 8") rims on a SHO if I had another one for the track.

Oh, and breaking the welds and getting a good alignment is very key. Dial in as much negative camber as you can. On my SHOs, I ran -1.5 all the time, and, with regular tire rotations, had no wear issues. For a track-only car with track tires, I suspect that -2 to -3 would work better.

Ron, Are you talking negative Camber on the Front or rear tires?

-Sam

 

[RonPorter]

Ron, Are you talking negative Camber on the Front or rear tires?

-Sam

Front.

I never messed with the rear. I know that there are some desirable rear camber setups, which require aftermarket parts, but others can chime in on that. I regretably admit that I didn't ever mess with the rears. But I also have never run track tires.

Nonetheless, proper F&R alignment settings are preety key for good SHO track performance.

 

[SHOmanBC]

Agreed that Drivinhard has most of it coverd, after the SHO is sorted out its real easy to drive at the limit because it will always have power on understeer, and a little lift mid corner will almost always bring the backend around.

Currently I'm running Koni's with 400/600lb springs and 22/26 bars, previous setup 600/600 and 0/26 bars. In the dry both setups feel very similar, however in the wet the 0 front bar setup is by far the faster. A ridgid chassis is a must, front and rear STB's, 4-6 point cage for HPDE stuff. Take a much weight off the nose of the car, bumper shocks replaced with rectangular alum., chuck the AC / ABS / sunroof glass etc. etc.

Brakes ..TCE Wilwoods, A,B,or H pads. 1 set of pads will last me 4 weekends at mission and that track is a brake killer. Rear generic organic pads...cheap and replaced twice per season.

Alignment: Front -3 camber min and as much caster as possible, 1/8 total toe out. Rear -2.5 camber, 0 toe.

8" wide wheels and 245 R compound rubber, Hoosiers are fast new and then fall off, Toyos get faster with use.....take your pic.

Its all about balance, just what the SHO dosn't have...put the battery in the fwd end of the spare tire well and build a 50lb "H" brace. This will help put some heat in the rear tires.

 

[Shoaz]

With coilovers/custom spring rates, the sway bar thing isn't as applicable, you just have to play around with it. Eric TT champ can chime in here.

Well, I just caught up with Les's previous setup a while back, and have 20/23 with 500/600 springs. Or 20/26, I don't remember off the top of my head (and I'm travelling, so can't check).

It was great until I had to add more ballast to meet my minimum competition weight, and after I added that last 30lbs in the trunk it became an evil-handling beast again (i.e., bad, no fun, slow). I'm moving 30lbs from the rear up to the passenger seat area, re-doing the corner weights and alignment, and will see what happens.

I think what I learned with that is that there can be a fine line between a fast, easy-to-drive car and one that is a nasty beast. I'm trying to get back to fast and easy.

Our tracks around here are medium-twisty without a lot of long straights, so there's not a ton of setup change required from track-to-track. What works best for a particular driver on a particular track might not work well for another driver on another track, though, and that doesn't consider other differences in the cars.

 

[PAracer]

Fuel vapor buildup in the gas tank...

That will put a quick end to a track session. I guess at this point we've concluded that the way to deal with it is to shield the gas tank from the exhaust pipe.

Brakes: I really liked the 11.6" cobra setup I had on my car. It may not be the biggest rotor on the track, or the fanciest caliper, but I can replace them with a quick trip to the pars store. Pads are really only good for one event anyway, and rotors can be bought locally for $20.

Chassis: Is there any reason why we struggle to get the chassis as stiff as possible? The springs, sway bars and Quaife all work to get power to the ground. The front is generally planted by the weight of the drivetrain. The rear is really just along for the ride. I don't really understand the reasoning behind adding bars and whatnot to make the car stiff. I'd rather let it flex and potentially keep the inside rear tire on the ground if possible. Don't confuse this with safety. That's the most important upgrade to a track SHO.

Weight savings: Yes! Yes! Yes! It doesn't matter where it comes from. If you don't need it, get rid of it. I don't care as much about weight distribution as I do about getting the weight down. How many of us have spent an entire weekend cutting loose wire ends, and shaving off grams of material only to find that the car is now 4 ounces lighter.

Suspension. Ground Control coil-overs with the SHO source upper mounts are the way to go. Not only are the spring rates much better for the track, plus adjustable corner weights, and ground clearance, but the whole setup knocks 50 lbs off the weight of the car. Half of which can be considered unsprung. As far as I am aware, Koni struts are the only acceptable choice (though more damping would be better).

Tires: Competition tires are pretty much all the same. From best to worst, your looking at fractions of a second, and hundreds of dollars. Go with whichever one makes you happy. I used Avon Tech-R tires from the Rack. They fit my 16x8" wheels and were perpetually on sale. Keep an eye on tire clearance at the fender and strut, especially after making any mods to the car. It's not hard to cause a rub. You can make wheel spacers fairly easily out of aluminum plate.

Cage, seat, harnesses, and a good steering wheel: Three of those are essential if you are at all serious about going fast. The steering wheel is the exception. The stock wheel is huge and thin. A good wheel from Momo, Sparco, etc. will be easier on the hands though the benefit is largely mental (It just looks damn cool). A wheel adapter for an sn95 Mustang will fit though you will lose your clockspring. Keep an eye on the diameter if you are planning to keep the car street legal. I know that here in PA, there is a minimum size, and it's not hard to find a wheel that's too small.

 

[SHOspazz92]

This is a great Thread.

-Sam

 

[drivinhard]

Pads are really only good for one event anyway, and rotors can be bought locally for $20.

My Wilwood "A" pads would last many weekends, although the rotors wore at a faster rate. I have never seen a more abrasive pad. I have never used a better pad either

I get pretty good (about 5 events worth) wear out of the carbotech XP10 and XP8 on the Z06, not sure if they make them in the stock SHO sizes?

 

[PAracer]

My Wilwood "A" pads would last many weekends, although the rotors wore at a faster rate. I have never seen a more abrasive pad. I have never used a better pad either

I get pretty good (about 5 events worth) wear out of the carbotech XP10 and XP8 on the Z06, not sure if they make them in the stock SHO sizes?

That's good wear. One event would wear down a set of HP+ pads about 70%. Since I don't feel like doing multiple pad changes at the track, I just tossed them. An 11.6" rotor would score and begin to crack after two days. Not bad enough to come apart on the ride home, but I certainly consider them to have been turned into scrap. Any rotor I tried had the same wear pattern, so I chose to go with the cheapest available. A set of rear pads (anything semi-metallic) will go for a whole season. The rotors that were on the car were the same ones I put on there in 2003 when I did the 11.6" rear upgrade. I had homemade bias plugs in the proportioning valve.

 

[Shoaz]

That's good wear. One event would wear down a set of HP+ pads about 70%. Since I don't feel like doing multiple pad changes at the track, I just tossed them. An 11.6" rotor would score and begin to crack after two days. Not bad enough to come apart on the ride home, but I certainly consider them to have been turned into scrap. Any rotor I tried had the same wear pattern, so I chose to go with the cheapest available. A set of rear pads (anything semi-metallic) will go for a whole season. The rotors that were on the car were the same ones I put on there in 2003 when I did the 11.6" rear upgrade. I had homemade bias plugs in the proportioning valve.

I can only guess that the tracks you go to are ******* brakes. I've been running on the same set of rear pads since I got the car, and on my old car I never changed the rear pads, either, and sold it with the R-4S pads that had been on it for years. I change front pads maybe twice a year (or a bit less), which covers probably 10-12 events. The tracks where we spend most of our time are fairly easy on brakes, so that helps.

And ventilation helps extend pad life quite a bit as well. If you don't have ducts or some way to ventilate the brakes, that may be contributing to your short pad life.

 

[Shoaz]

Chassis: Is there any reason why we struggle to get the chassis as stiff as possible? The springs, sway bars and Quaife all work to get power to the ground. The front is generally planted by the weight of the drivetrain. The rear is really just along for the ride. I don't really understand the reasoning behind adding bars and whatnot to make the car stiff. I'd rather let it flex and potentially keep the inside rear tire on the ground if possible. Don't confuse this with safety. That's the most important upgrade to a track SHO.

Wanted to comment on this before I forget.

Since a lot of suspension tuning involves tweaking the opposite end of the car to get one end to work, e.g., stiffen up the rear to increase front grip to reduce push, chassis stiffness is important. The less rigid the chassis the more difficult to tune handling by adjusting bars and springs. Using the same example, trying to reduce push by stiffening the rear would be ineffective if the chassis flexed more than the rear springs.

Even with an ideal, perfectly stiff chassis, increasing the suspension spring rates shortens the transient responses and makes the car respond more quickly to smaller control inputs. If that's what you were asking.

 

[Michelle]

I think the female driver is the best setup for the road course. :theyareontome:

 

[K-Dawg]

I think the female driver is the best setup for the road course. :theyareontome:

Yeah, it scares all of the other drivers off the track...

 

[Shoaz]

I think the female driver is the best setup for the road course. :theyareontome:

I don't disagree with that at all.