Erics_02_z06

so short of getting coilovers, what is recommended? I was thinking about just doing poly bushings and some new shocks and sways. What is a popular configuration? I'm not planning on tracking the car a ton, but it will see some track time

travisnd

Leave it stock and go get seat time. The car is great right out of the box. Avoid polys unless it's mostly a track car.

Erics_02_z06

tire/rim size ideal as well?

AlanC

Having had coilovers on my car in the past I would say they are a lot more trouble than they are worth.

I second travisnd's comment about leaving it stock and getting the seat time.

I had an 02 Z06 and put a lot of track time on it and we never did anything to it besides the following and it never skipped a beat.

• Lowering and Performance Alignment
• Track Tires
• Track Brake Pads
• Stainless Steel Brake Lines
• Race Seat and Harness

I now have a 2000 FRC with an extensive list of mods and I really can't say I'm having any more fun than I did with the Z06, although I am certainly spending a lot more money and working on it more often.

Alan

travisnd

C5Z06 wheels tires are perfect for the job... most of us race on them because you can't find a rim any stronger or lighter. Plus they're cheap and relatively easy to get more if you need to.

If you're new to all of this just make sure your pads have at least 1/2 thickness left, your brake fluid is relatively fresh, and go get seat time.

If you enjoy it then get a seat (the stock ones suck) and a harness bar and harnesses.

Then get some stickey street rubber in stock sizes like a Nitto RII or Toyo R888 etc. At that point you'll probably want to upgrade your pads to a track pad.

All the other crap is a waste of money for the most part.

AlanC

Yep. And even the stock Goodyear Supercar tires are pretty good for track use. We ran the Open Track Challenge (7 tracks in 7 days) on them one year and they were great.

Solofast

You don't need to do much. Most of it is all in there already. What you should do is cheap and doesn't take much time to do. You need to do the first two because they are cheap and will extend your tire life at the track to the point where it will likely save you money. Most of the rest is maintenance.

Lower it 3/4 of an inch and corner weight it.

Why... It is cheap, and you want to do that before you do the next thing (which you really need to do) anyway.

Put on an agressive alignment.

Why... You won't burn off the outside edges of your tires at the track. It will pay for itself in tires saved on the first track day. Novice drivers sometimes overdrive and if you do you will toast your tires. Best money you will ever spend and the car will be more fun to drive.

Put on a set of brake cooling and spindle ducts.

Why... The cost is minimal and even at a novice level it will save your brakes and you won't worry about bleeding cooked brakes between sessions. While some novices dont use the car to its capabilities, others brake too much and are hard on the brakes. Get it done and out of the way.

Look at your tires. If they are old or need replacing upgrade to something that can take the track abuse.

Why... If your existing tires are shot they could cut short your track day. Moreover, a better street tire will let you have a lot more fun on the track.

Think about shocks.

Why..... If your car has over 30k miles on the stock shocks you should replace them. Bilsteins are the best bang for the buck. It's no fun to have a floaty car when you are trying to learn, and all it will do is engrain bad habits.

Maintenance...

Fresh fluids, bleed the brakes (brake fluid in an 02 has been in there a long time and will boil prematurely. While you are at it, inspect the pads and replace if necessary. Also inspect your belts and balancer, replace as necessary. Change the clutch fluid.

Done.

Remember that bringing a poorly maintained car to the track is likely to end up with a wasted afternoon when something goes wrong. Do a little maintenace and it will pay off big time.

Erics_02_z06

awesome help guys. I've got 42 on the shocks so I'll replace them. Shock question:

c6 z06 vs Bilstein?

Also, the previous poster said not to get poly bushings. I was only thinking about getting them because I heard that without them, there is too much deflection will will negate the effects of the allignment. Is this true/not true?

But I really appreciate all the help. I'll be doing a seat/harness, steal brake lines, fresh tires + agressive alignment, new shocks, brake cooling ducts, and fluid changes.

One final question. I've heard that lowering the car too much can have an adverse affect. Is there an A-Arm angle I can measure to find the optimal drop for the car? I don't know if the car has been tampered with since I'm not the original owner, so dropping it 3/4 might be way too much if the car has been previously lowered.

thehammer69

IMHO...a better suggestion would be Pfadt's Sport Shock

argonaut

The poly's are definetly good for handling but the problem with them for a mostly street driven car is they are harsh and do take some amount of maintenance that the stockers don't. Personally they were lower than sway bars on my list.

wtknght1

Don't lower the car unless it's done by a pro shop that knows the EXACT perfect height. You can really screw up a great handling car by doing that (suspension geometry, bottoming out shocks, etc.)

For now, leave the car alone including the shocks. Get lots of seat time and enjoy the car and the reliability. When you think you're ready, take it to a shop like Phoenix Performance, stick a set of T1 sway bars on there, corner balance it and tune the engine and run the **** out of it!

Joe_Planet

I just bought a c5z and i'm worried about blowing the engine, as my stock c6z blew the motor after 3300 miles. Does the ls6 have the same problem?

Z06trackman

This is not true. The deflection is a function of the grip you have. What is true is that you do not need as much static chamber with polys to produce a given chamber while the car is loaded with lateral G. It is also true that polys will make the car feel more like a race car. However, many folks have fabulous handling cars, with even-wearing tires using the stock bushings. Proper alingment makes all the difference even with the stock bushings.

wtknght1

No. They're pretty much bulletproof.

Erics_02_z06

alright, I've got a plan now, thanks. Does anyone have lowering measurements that I can use to lower my car though? I figure fender height isn't the best way...is there a consistent way to measure so I can just copy what you've done? I'll be using stock rims and tire sizes

sothpaw2

Eric,

Ignore the fenders as the body position on the frame isn't perfect.

Best I can say is to lower the fronts almost all the way--leave 1 thread before before bottom out. When you do this, measure the number of 360-degree-turns it takes on each side--you want to lower it evenly assuming this is factory set (previous owner did not change it).

On the rears--I would again bring it down with full turns and be sure to do it evenly, RR same as LR. How far down? Here I measured the car on the frame rails at the jacking (hockey puck) points. You want to lower so that there is .25-.5" MORE height at the rear jacking point. When I did this I got about 4.75" F rail and 5.06" rear rail.

For measurements, since a garage floor is not perfectly level, I pick 2 points on the floor and measure the rears there. Then move the car backward so the front jack points are over these same 2 positions. Now I move the car again and get a second full set of measurements with the car facing backwards. Average the measurements at a corner...this averages out the left/right imperfection in the floor. Approximate but better than nothing.

A good check when you're done is to measure the A-arm height left to right on the Front and rear to ensure that you don't have wildly higher left vs right heights. But if you start off factory and do things evenly...you should be ok.

Z06trackman

Solofast said:

He said it this way because trying to lower the car without a corner weight is a guess at best no matter how precise your height and turn measurements are (plus your corner weight is likely off now). The weight is much more sensitive to adjustment than rake, so measure from the frame to get your rake, then make the final adjustment on a set of level scales. Your local dirt track shop can tell you who does corner weighting if you don't have someone. Don't forget to sit in the car. The goal is to get the LF and RR total = the RF and LR total. (within 1/2% or so)

sothpaw2

However, I'd add, the couple of shops I've talked to about cornerweighting are hesitant to do it on a leaf springed car. I think the settling of the spring makes precision difficult. For HPDE, I'm hoping that an educated guess is as good as factory which is good enough. For real racing/TT, I can see being more adamant about getting this done.

boogienights

Fantastic, thank you!

SunnydayDILYSI

My $0.02. I generally agree with the above, but if this is mostly a street car I would not lower it. The benefits on track are marginal but the scraping on the street and curbs on the track as you learn will be greatly increased. I learned this from experience as I cracked a front fender while rolling my right front wheel ~3/4 of the way up an curb on an apex (cracked fender behind the wheel on way back down). I also did poly bushings which do help on track, but make the car undriveable on the street (loud squeaks and very harsh ride). Camber kit helps enables a more aggressive alignment and is a good investment (it keeps the alignment in tact even when you spin out, I was constantly getting into alignment issues without it). But this will wear your tires quicker on the inside if you put a lot of street miles on it. The increased wear is reduced if you don't put in much tow.