azjagster

Road course.

kyle242gt

As a new owner getting ready to track my 08 for the first time, how big a deal is this? Coming from a Miata, I don't imagine I'll be driving the Corvette anywhere near its potential any time soon.

Here's what I did:
Brake pads (Carbotech XP10 and XP8)
ATE200 fluid (I've since learned that may not be good enough, but see my comment above about taking it easy)
Alignment http://www.billswebspace.com/Corvett...ev20110912.pdf
Rear tow hook

Z.06

Actually there is another path to protecting our pre-09 Z06 engines from oil starvation in left hand corners, and that is to increase the engine oil capacity to 10.5 - 11 quarts. This has been well proven by a CF member Dreamin, and has been working fine in my 08 Z06 for a couple of years. My home track has a long sweeping left hand turn where my car sees WELL over 1 G for 5 seconds, and there have been no problems. I have an Lingenfelter modified dry sump tank which increases my engine oil capacity to 11 quarts. GM found an equivalent solution where they added a pony tank to raise engine oil capacity to 10.5 quarts for all of the dry sump cars from 2009 on. With the Z06 it is easy to corner at more than 1 G on street tires, like Michelin Pilot SuperSports or Pilot Sport 4s. Make sure your engine oil system can keep pace.

Don't sell your old Miata short, there are plenty of them which have been modified and lightened sufficiently to make a Z06 sweat on many tracks. Actually, coming from a Miata, I suspect that you have already learned how to conserve momentum, which is a valuable asset in any car.

Looking at your list, the modification which I did not find is shock absorbers, and you did not disclose the model and age of your tires. The very first modification I made on my 08Z06 was the shocks. The OEM shocks were horrible. I am using DRM revalved Bilsteins, which I installed when my Z06 was new. They are OK, as are the Bilstein Sport Shocks. Of course more money brings other options to fore.

80atez

PLEASE just track your Z06 and enjoy.... It's ready if you are....


Oil starvation happens only with slicks if i remember right. I replaced my tank with a lingie, but have never put on slicks. Probably was not necessary. Just piece of mind. My track has a 270 degree RH turn I was worried about.

I would not worry about running a stock Z06 of ANY year on a track for several events in a row. Just check brakes daily.

The above stuff is all good info for eventual mods, but don't take it as necessary for a track day or weekend.

DOT 4 fluid after your first day is probably a good idea. I've run Motul 600 without regret. I use carbotach one piece pads (xp8-10 rear, xp 12 or enduro front) and have had them reworked with SS pistons in front.

I have coilovers and sways too, but after many days of tracking first. I found coilovers (LG G2) were the only way to prevent rear end pendulum effect on rough roads, and I think they help prevent snap oversteer on track. I love that mod.

I agree and endorse Lawdogg's post above because he's awesome, and it is the obvious choice, EXCEPT... I have been steered away from "bushing" my car because I hear the street ride and sound can suffer. Again, without slicks, I'm not sure you need to go that rigid...

I've not yet gone aero because I stopped tracking my car due to life, but that would be my next step, still without bushings and then with slicks... I never wanted my car to be a "track only" car...

I would add I put a one piece track seat in and 6 point harness with bar (possibly stiffens the chassis) and it really really helps with feeling the track and the car movements. With a HANS, I feel it is a safety improvement too (this is open for debate without a cage), and so I'd put that after brakes if you know you're going to track it for a while.

...Engine last (except heads).

GARY2004Z06

At some point you decide to do a clutch/FW, you can pick up a fair amount of HP and make the car rev quicker by choosing a LW clutch and aluminum FW.

kyle242gt

Is swapping a later tank an option?

No question. I hope to hang on to it, space allowing. I'm somewhat nervous the Corvette will be too fast to be fun.

Shocks are stock, 51K on them. I can feel there being some room for improvement there, but ... baby steps. Tires are ~5 years old, 70% F, 100% R, 275/325 MPSS.

Thanks for the vote of confidence!

Dan_the_C5_Man

This.

Hib Halverson

I'd start with:

Alignment and tires.
Brake pads and premium brake fluid
0W40 engine oil
Upgraded trans and axle lubricants.

Then, I'd get my track driving skills to the intermediate level.

Once you are there, then I'd consider additional modifications for the engine and the suspension.

C6Z06Silverbullet

I kinda disagree with that statement, with a tune headers and exhaust should add about 25HP

80atez

That's sound advice for starters. I've always used the OEM rear diff fluid as it matches the clutch plates. What do you consider an "upgrade" from that synthetic fluid? Thanks.

Apocolipse

A tune will ad 25hp. The rest nothing.

kyle242gt

Just did my first track day in this car, Laguna Seca, about 75 ambient temps. All stock with Carbotech XP10/8, MPSS in stock sizes.
Aligned it:
F -1.2 camber, 8 caster, 0 toe
R -0.8 camber, 0.2 toe in
Tire pressures: ~32R ~37F cold, ~38R ~41F hot.
Tire temperatures: even at ~125 R across, RF was ~125/135/145 suggesting more camber needed (CCW track, not surprised), LF was about even at 125.
Engine got to about 205F, oil about 235F.
Max speed about 120.

After I figured out what I was doing, I really felt like I needed more tire. I get that everyone's different, but does that sound reasonable? IE a (somewhat) experienced driver reaching the limits of the Michelin tires in a single day? I found the fronts got greasy and pushy, and the rear was ready to step out any time I gave it (too much) gas on corner exit. Or perchance I still just need to come to grips with the power of this thing and stick with the stock tires for a while?

Thanks for any advice.

Apocolipse

Sounds like you needed less tire pressure to get some extra grip.

kyle242gt

I may be out to lunch here, but if tire temps were even (or even gradient) how would less pressure help?

jorge18

Tire pressure seems a bit too high. Just did a track day this weekend and started with 28 cold, aiming for 32-34 hot (as per our resident racer/instructor, @Mordeth )

kyle242gt

Thanks for the followup - any chance you've got a link to discussion about this? I'd been under the impression that tire temps were a better way to judge alignment and tire pressure than static pressure.

Kind of a bummer to hear I left some grip on the table.

Mordeth

You need more negative front and rear camber, and a small bit of toe out for the front. This will help a great deal with turn-in and overall cornering grip and greatly extend the useful life (and grip) of your tires on a race track.

How old are the tires? How much tread is left? How are you measuring tire temperature? Do you use a probe? How quickly after you exit the track do you measure it?

After you get into the pits, tire temp measured and compared across the tire (inside, middle and outside) will tell you how well your alignment is set up and how well the tire is responding to your car setup, driving and track conditions, but it won't necessarily tell you whether you are at optimal OVERALL operating pressure and temperature for that tire and your car and that track. The best way to target a HOT psi as you can measure this ON THE TRACK. So you start at for example 28psi cold across all tires, go out for a session and on your cool down lap check all pressures on the DIC and mentally note them. Any tire above 34psi HOT should be taken down to 32-33 psi (so if you see a 40 psi tire on the way into the pits on the front left, you mentally note that you need to take 6-8psi out of that tire, regardless of what you see after you get into the pits, get out of the car, and measure). You do this repeatedly until the tire stabilizes at a certain pressure on the track (which is ultimately a temperature). As the day progresses, the ambient temps increase, the track heats up and you get faster, you may find that repeated bleeds are necessary until the tire stabilizes. You still measure the heat gradient across the tire using a probe, but this is to tell you about the setup of the car and how the tire is responding, not whether you are at an ideal overall pressure/temp while ON THE TRACK. By the way, the next morning you might find that you are at 23psi cold on the FL, 24psi on the RR, 25psi on the RL and 23 psi on the FR or some such example. In which case you start the whole process over again (don't go out with 23psi cold on an MPSS for HPDE). So now you make the necessary adjustments to starting cold pressure (maybe this time you start 27psi cold on fronts and 28psi cold on rears), and bleed down as needed in between each session as the tire heats up during the day. In a race, you only get one shot at this.

Depending on the track layout, alignment, car setup and your driving characteristics - different tires (and different corners of the car) will heat up at different rates. As temperature and pressure are directly related, pressure will go up accordingly as well. You want all tires within 1-2 psi of each other ideally (hot). So different adjustments must be made on each individual tire as appropriate. And again it is circumstance and setup dependent.

For MPSS, ideal HOT pressure is 32psi - 34psi (this is not only from a massive amount of my own testing but also from Michelin themselves), with anything over 36psi being too much. At your outrageous tire pressure (41psi hot), the tire is not operating at either the ideal pressure or temperature range for maximum grip and maximum longevity. It will become greasy and wear unevenly (middle tread will show more wear than outer and inner tread). You want only enough pressure so that the sidewall doesn't roll over and so that the tire isn't "soft" (which can damage the tire). On my Hoosier R7s I start at 22 psi cold, targeting 32 psi hot for a race. On Hoosier A7s I start at 20 psi cold and 31 psi hot for a race. On MPSS for HPDE I start at 28psi cold and target 32-34psi hot, and bleed down as necessary. For NT01 I start at 27psi cold and target 33 psi hot. I find these pressures for these tires on my car to be optimal (ie., maximum grip, maximum longevity and not damaging to the tire). All tires are bled down as needed to maintain the ideal tire pressure through the day. My alignment is already perfect and my temperature is already consistent across the tire (within 5-10 degrees). So all that matters is tire pressure (which is uniform heat). Even if your alignment is off (as yours clearly is), you still should be targeting a specific HOT PSI for all tires, which for you is 32-34psi (and never more than 36psi).

So you manage the alignment and car setup (in part) by measuring the heat gradient across the tire. But you also must manage the overall tire pressure (independent of the heat gradient) as there is an ideal pressure for these tires, your car, your setup and the track you are on. Much of it will also come from your own personal testing and feel, but much of this information is already known within a certain degree of accuracy (so you can use this knowledge as a basis to begin your own testing). If the tire gets greasy at 38psi then lower pressure to target 36psi or 34psi, or 32psi. If you mark your tire with chalk from the tire tread down the sidewall and you notice the sidewall chalk is worn off then you likely have too little pressure (or if the shoulder and edges of the sidewall are worn). If the middle of your tire is worn more than the outside and inside then too much pressure. You do this by bleeding or adding pressure on individual tires after you have recorded them HOT and investigated what has happened to the tire (by looking at it) and how the car felt. The heat gradient you across the tire (in the pits) is very useful (for setup purposes), but not necessarily for determining optimal overall pressure/temp.

Here is what Michelin has to say on the matter (and ideal hot pressure for MPSS). Note how they stress that YOU YOURSELF can find the ideal optimal hot pressure though testing (which is dependent on a variety of factors). Please take note of this, as I have also mentioned it above.

kyle242gt

Thank you very much for all the useful info. In retrospect, I should have done a little more due diligence on this before heading out. Coming from a Miata, I basically was thinking reasonable temp gradients at the end would be the answer.

I didn't want to go too far on the camber my first day; since I still have the Miata and wasn't sure how terrified this would be, I wanted to keep it on the streetable end of the pfadt suggestions. Same thing for toe-out in front, didn't want to make it darty. My lone concession was rear toe-in to get away from the (then assumed) rear instability. After seeing the before specs (about 0.20* rear thrust angle), I might have gone a little less rear toe, frankly.

Tires are garaged, 80%+F 100%R, about six years old front, four rear (give or take). I've been under the impression that garaged tires don't degrade too quickly, so wasn't real worried about them drying out (or whatever).

Temps were measured with a Longacre immediately after pulling in, inside/center/outside, RF/LF/LR/RR rotation every time for consistency. I didn't measure cold pressures, rather lowered hot pressures to address temp anomalies.