lostpatrolman

DaveL82, where did you order your superlites from?

72 RAY

Thereisnospoon,
This is a tuff one!
I would have to say the engine is the most bang (literally). The most dollars and the most improvement.
That being said it only works this way if you have done the other stuff.
Meaning make the car handle as best as you can on the track. Then when you add the H.P. all you have to learn is throttle management.
Now this raises an interesting chain reaction and the DIHLEMA.
STREET OR ROAD RACE. It's very hard to have a dual purpose car if you are competative in nature. You will think this is good enough but when that guy with the Wilwoods out brakes you into the hairpin. You will start looking up kits on-line the next time you get a chance. Hence the race-upgrade, race-upgrade money pit.
I went with the suspension, brakes and trans first. Then the steering. Then wheels. Then the motor (includes exhaust and ignition and guages). Then to all of the cooling issues. (Coolers on everything). Once it was working OK, I had to learn to drive it. (very easy on the gas pedal). THEN (this is the part I hate) back to wheels (wider). Then brakes (wilwoods) and then to the suspension (adjustable a-arms and steel bushings).
You see as my skill increased so did the load on all of the components. Braking deeper, going faster into and out of the turns. Basically where does it stop. Well it doesn't.
THE DIHLEMA!
In hind sight I should have build two cars one for the track and one for the street. My car now is more race than street. It's a monster on the street and I love it but it demands your respect. (street tires just don't handle like race) I'll say no more.

I'm rambling here.

Advice- Have a plan and work it. Build the car around the motor (eventual if needed). Mostly just get out there and Drive , Drive, Drive. The mods will come to you as you gain experience. A 600 H.P. motor will do you no good if you can't drive it. In fact it could hurt you. Work your way up and ask questions along the way.
Good Luck!!

72 RAY

Parts to keep an eye on.

Steeroids brackets cracking. In my opinion the passenger side bracket needs some extra bracing. Better yet weld them up.

VB&P smart strut bracket. (the one that attaches to the pumkin). Also prone to cracking. I totally boxed mine after it cracked three times.

Also the transverse spring bolts for the pads. Loc-tite these and check them after each session.

Lastly nut and bolt everything after each weekend (or before). Even check the a-arm bolts. I lost one on the street once (no fun). Thank God it was not on the track.

Anybody got any other checks?

ThereIsNoSpoon

Thanks a lot 72 RAY! This thread is gonna be the end of my bank account.

427V8

I have raced at Brainard MN. a nice 3 is mile road course. The club I run with puts me into the modified class because of my aluminum heads, so I am competing with modified C5's

I wasn't too bad, I could keep up with the wrx that was there he was a tad faster in the corners but I was a lot faster everywhere else, but I was running BF goodrich Radial T/A's a horrible tire!
Well I went off turn 1 at 105 and while I didn't break anything I went on a mad rampage of upgrades, and got layed off in the middle of it which slowed down the upgrades.

That was 2 years ago and I am finally getting everything back together.
I went with Wilwood brakes, front and rear. The fronts also have brake fluid recirculators so they will never boil the fluid again! And with 13" rotors I should have all the brake I need.

Steering is now a home made rack and pinion with super heavy duty brackets, re-enforced 1/4" plate steel things that everyone here said was extreme overkill... I am just finishing up the power steering install. I was going to try and run manual, but she is just too heavy to throw around corners without power.

Iam also running 255/35R17 Kuhmo escta in front and 275 in back. These tirres stick very well. prolly not as good as Hoosiers or anything but compared to the old T/A's they are like glue.

If anything I have a bit of understeer, but I'm sure I correct that with a little right foot action to the 434 smallblock.

I can't wait till I can run it again, but that will probably be next spring.

turtlevette

here's a general info clutchdust started in the road race sect.
http://forums.corvetteforum.com/show...6&page=5&pp=20

I've never really run on a good tire yet because i'm too cheap. I think that's 80% of my slowness. Radial TAs are junk even the 295/50/15s i ran squeeled like a banchee. The 255/60/15 Firestones i'm on now are even worse. Once these tires are done i will never buy a 60s tire again.

It seems my car understeers in certain lower speed turns and oversteers in high speed turns with the back end feeling very light in the high speed turn. I feel this is very dangerous and need to do something about it. Wider tires in back will help. I have gone to a softer spring in back to decrease oversteer but it didn't seem to help much. This light feel in the rear end keeps me from pushing the car like i need to to be fast.

jackmoore

If you are letting the car hang out, maybe an approach change. You set the car up earlier in the turn by hanging it out there and using the throttle to push it through. On a road course I think you can actually run a little faster that way. That's one problem with little slalom courses, they don't really replicate GT or road racing. Everything is so compressed that it favors little cars.

turtlevette

yep,

i need to get back to basics and do all my braking in a straight line rather than trailbraking into a turn and make sure i push my apexes out later rather than earlier.

I need to attend more events and get more seat time.

72 RAY

I to was fighting oversteer for a long time. Can't say exactly what I changed but now I'm pretty nuetral.
Mechanically I went to steel bushings everywhere and removed the rear sway bar. I have the dual mount from VB&P.
I put about 3/4 neg. camber on each side and set the suspension on hole #3 (the same as the front).
The key I think is the tires. If I run some worn tires up front I have understeer. If thay are used in the back then I have oversteer. With a new set the car is great. Of course you can't run new tires everytime so you have to do the best you can.
Mostly it comes down to your foot. With a 7000 rpm 434ci Monster at my disposal throttle managment is key.
It's all about seat time, which means more tires, which means mo-money.
That's why I'm going to work right now. So I can play in a couple of weeks.
Later!

norvalwilhelm

Doesn't removing the rear sway bar change the car from oversteer to understeer??? The removal of the rear bar could be the reason you no longer have oversteer.

StingrayDK

VB&P recommend that you remove the rear sway bar when you install the dual mounted rear spring, for the same reason.


This is a great thread

Wrencher

Exactly. I have not run my vette (no rollbar yet), but I get my BOSS 302 on track 4-6 times a year. With a fresh modified engine, stock brakes (with good pads) and no-name 60 series tires, it's good for about 10 laps before the brakes are GONE. Surprisingly, the tires get real hot and goey with acceptable traction, MUCH better than the Goodyear RSA plus's I ran at first.

So my experience is similar to most of the others. I will definitely upgrade the brakes, and go with alloy rims and probably Hoosier tires. I want to do this on both cars, but the Mustang will probably be first due to limited funds. I'm having a blast, even with my antique cars!

Hans

69autoXr

Definitely. And the fact that his rear tires look much wider than the fronts, this will reduce oversteer.

BTW 3500 lbs is very heavy for a '72, why is it so heavy? Running a big block? I see your car is fully trimmed out, but 3500 lbs?

edit: reread, 3500 lbs with driver, got it now

69autoXr

245-50-15 Hoosier R3S04 will work nicely. That size is only offered in the "R" compound, as opposed to the "A" compound (A3S05) which is softer for autocross, the slighter harder compound R tires will work well for track days. A friend even autocrosses his 72 on the 245 R Hoosiers and does fairly well with them on a stock Corvette.

Twin_Turbo

yes, a good thing to remember so you don't get confused as to what effect a change has on cornering, a tire only has so much adhesion and when cornering it's used to corbner but when you put some other load on it it detracts from the cornering ability, so using a stiffer roll bar means less roll but more weight transfer in the outside wheel, do it in the rear and hte thing could become twitchy and oversteer, and vice versa...stiffening the front sway bar to reduce body roll has the same kind of effect as softening the rear, what you do where depends on how stiff you want it and if you can get away w/ it. For fast times acceleration out of the corner is very important, those that have the best balance between cornering speed and traction out of the corner without the rear end breaking away usually record the best lap times.

69autoXr

Lower A-arm rear mount extensions should be gusseted. The welds here are prone to cracking.

Twin_Turbo

* Hole for steering ram bracket mounting plates should be welded over. (the big hole in the frame where the steering box mounts)
* Frame horns gusseted for stiffness of sway bar mounts

norvalwilhelm

About a year ago this was a hot topic. Most of us have welded up the lower A arm channels and added gussets already.

I am actually installing a rear sway bar this week. After reading Herb Adams on how to set up a vet I went all the way to a 1 1/4 rear speedway bar but only .187 thick.
I want to do some testing in a local large vacant parking lot to see how it compares with and without a big bar installed.
I am running a speedway 1 1/4 front bar with bearings rather then bushings.

69autoXr

How about this one...the pinion mount bracket welded to the frame crossmember can be torn away if it is weakened by rust. Then the pinion will be free to pivot up and down as torque is applied and released.

turtlevette

be very carefull. If you go overboard with the rear bar the thing will be very loose, oversteer like crazy. You had posted a thread earlier where you were in a high speed sweeper and the car got loose on you.

I like lots of oversteer on an autoX course cause you can really whip the rear end around faster. Just disconnect the front bar when running autoX.

For the road course you want a car that understeers until you get really good. Don't want to loose it at high speed. Two weekend warriers have been killed this year at DE events.