Olitho

I have a new set of Good Years I am running at a double regional this weekend at WSIR.

What hot and cold tire pressures are you running with Good Year GS-CS tires on C5 Z06's?

Is there a knowledgeable distributor or manufacturer number for asking dumb questions like this?

Who is running nitrogen in the tires? Is it worth it or just making life more difficult at the track?



Fastest regards,


Oli

John Shiels

When I ran them I would be at 33-34 F and 31-32 rear and end 40-41 hot on all 4. If you have practice time take the temps. I had 275 & 315 x 17

Jaymz

I was in the same ballpark.. 34F & 32R when I ran them.

Olitho

Thanks guys,

I have never run these tires before....

And I have no practice this weekend, just a 15 minute qualifier and then the race.

Those pressures are a bit higher than I was told by another driver. I will give those pressure ranges a shot.

Does Good Year have a site for this info?




PS. How ya doin' Jaymz?

BuckeyeZ06

29-25 cold on 315s all around.

John Shiels

If I ran them lower I would have rolled them off the rims

BuckeyeZ06

OK...but I never had a tire come off the rim.

Olitho

I will let y'all know if that happens to me this tomorrow.

More than likely I will get bumped and spun again!

John Shiels

figure of speech. I would have ruined the shoulders. Enjoy think positive my moneys on you!

BuckeyeZ06

It's all good.

Funny thing, is when I first started racing I used Goodyear (as opposed to Hoosiers today). I got these pressures from Kryderacing, and Reed Kryder (patriarc of the business) is a former Goodyear motorsports engineer. I also think John Heinricy suggested these numbers to me (at least the 4 lb f/r difference).

When I first heard that the pressures were to be so low, I too, was surprised. I was thinking more in the 34-35 lb cold level.

trumper Z06

GSCS 17 front/18 rear... 32 front/30 rear cold... shoot for 40/38 hot.

These pressures was according to a Goodyear tire engineer when they 1st came out.

I've been using Kuhmo V710's... 315/18's... for the past couple of years.

IMO... they "stick" and wear a little better !!!

NJCRUISER

Dave, before we switched John's car over to Hoosiers at runoffs HPT, we ran the new GSCS's at no higher than 31 cold. And we did use nitrogen. It was also pretty damn cold there as you remember. My back still hurts from moving, draining and filling some 50 tires with the gas. LOL

BuckeyeZ06

Evan,

maybe my memory isn't what it should be, but I distinctly remember going "low" at Summit Point 2004 (my first national race). What causes this to stand out was I fully expected the pressures to be higher. I did use straight air, as opposed to nitrogen. Doesn't N2 increase pressure with temp at a lower rate? If so, couldn't you start at higher cold pressures? This may explain some of the discrepency.

BTW: I normally am a bit higher on cold temps in my Hoosiers compared to some else we both know.

Olitho

I won my race group fairly handily today... by almost 30 seconds. The disappointment was that I was the only T1 car entered. John Norris (BMW ITR)was a good race for about the first four laps, but he went out on old Hoosiers and those things really fell off after about four laps. I was on the pole, but I did not like the feel of my brakes into turn one so I let him by on turn three and just followed him to bide my time. During the pace lap I did not warm my brakes at all, so when I went into turn one they felt soft. On turn three I let Norris by until I could determine if they were OK. They seemed fine after turn one, so when I started to pressur Norris he was all slippin' and slidin'.

I was not on new rubber either, but fresher than Norris'. My tires were not my new Goodyears GSCSs. I went on on the GSCS scrubs I got with the new set from Chris Ingle. They were in pretty good shape. From this first experience I have a few observations:
1. They don't seem to wear/last as well as the V710s.
2. They are very controllable and predictable at large slip angles.
3. They don't seem to be as fast as V710s, although I was not pushed very hard today, so I did not really work them to the edge of my ability
4. I kept bleeding off air. I started off around 32r and 34f psi and in all three sessions I came in around 41-44 psi.

So I never got to run them at the recommended pressures. I will try that tomorrow in qualifying and racing, although they are going to be so "done" by the end of the race. Norris in his BMW is going out on new Hoosiers Sunday. Based on his time today heat cycling them in, I am in trouble tomorrow. Norris is running A3S06s so it will be interesting to see how they hold up for 30 minutes. Hopefully I can up my game and make the tires last to hold him off....

Thanks for all of your feedback and recommendations,

Oli