A6 & Z06 pressures for autox

[froggy47]

I've been on 710's for 4 years & ordered a set of H's to try.

I know what I like & what works on the 710's & I have heard H's want more psi.

Suggestions? Autox. Maxed alignment.

[SSSUPRA]

I've had good luck with hoosiers at 29psi but depending on the surface I sometimes run them at closer to 32~33psi. I'd really like to hear what others have to say though since I only have one season on H's.

[froggy47]

Looks like I'm gonna try +5psi f/r over what I was using with the 710's & take it from there, take some tires temps each run.

[dgoetz]

I am going the other way, hooisers A6's to Kumho 710's. I ran Kumho's on my CP Camaro but switched to a 04 Z06 SS for this year. I used from 32lbs frt & Rear to 38 lbs, but never found the best pressure. The higher pressure (36lbs) worked the best but the tires wore even faster and uneven. Found out the Hoosiers have more traction when new but would loose traction well before being used up. The Kumho's for me are more consistant and will last right up to almost corded.
I will use 295/40's and 315/35's K's as comparded to 295/35 and 315/30 H's, AX alignment, Pfaft SS Sway Bar, Pfaft Shocks.
So what air pressures were you using in the Kumho's?

[froggy47]

pm sent

[VettesRule]

32 front and 28 rear. Stock shocks with competition alignment.

[DennyM]

Originally Posted by SSSUPRA

I've had good luck with hoosiers at 29psi but depending on the surface I sometimes run them at closer to 32~33psi. I'd really like to hear what others have to say though since I only have one season on H's.

Thanks for posting!

[mjorgensen]

I ran the White Cobra in ESP since 98' and have been a KUMHO contract driver the last few years. I would definitely tell you you can go much lower in pressures on the V710. Our cars in equal trim are about the weight and I run about 21 rear and 24-26 front. They will wear faster but not much and give you much better feedback at the limit than any other brand. The higher pressures do not allow enough flex in the tire to heat quickly and make it less controllable at the limit IMHO.

Originally Posted by dgoetz

I am going the other way, hooisers A6's to Kumho 710's. I ran Kumho's on my CP Camaro but switched to a 04 Z06 SS for this year. I used from 32lbs frt & Rear to 38 lbs, but never found the best pressure. The higher pressure (36lbs) worked the best but the tires wore even faster and uneven. Found out the Hoosiers have more traction when new but would loose traction well before being used up. The Kumho's for me are more consistant and will last right up to almost corded.
I will use 295/40's and 315/35's K's as comparded to 295/35 and 315/30 H's, AX alignment, Pfaft SS Sway Bar, Pfaft Shocks.
So what air pressures were you using in the Kumho's?

[SSSUPRA]

Originally Posted by DennyM

Thanks for posting!

Pleasure.



I checked with hoosier yesterday and they say for a car in the 3000lb range you should be at 37 psi hot and 3 deg negative camber. There may be some truth in the pressure but I can't imagine 3deg on a Z. Regardless I'm going to try it at my next event.

[dgoetz]

This is exactly what I found when I talked to people at Ax events about what air press they are using in the same and similarity set up Corvettes. There is no set air pressures. I realize that some of them could be lying but I don't think most are. These are drivers from my caliber (4yrs) to past National Champions. With Hoosiers on a C5 corvette I have heard from a high of f-36lbs r-38lbs to a low of f-30lbs r-26lbs. The only thing that was close to consistant was most used 2-4lbs less press in the rear.

[froggy47]

Ran 35/32 & 34/32 (last run). May go a bit less next time. Tire could have rolled over about 1/2 in more & been ok.

Temps were about 145 f with infrared , very hot San Diego day. (I know not accurate like the pyrometer that sticks in.)

These did not seem to gain as much pressure between runs as the 710's, not sure why.

Fun tires.

[mjorgensen]

Tires gain pressure from "working" the sidewall and tread. The more they come up the better the tire is gripping at least to a point then you are over driving them so it is a fine line.

Originally Posted by froggy47

Ran 35/32 & 34/32 (last run). May go a bit less next time. Tire could have rolled over about 1/2 in more & been OK.

Temps were about 145 f with infrared , very hot San Diego day. (I know not accurate like the pyrometer that sticks in.)

These did not seem to gain as much pressure between runs as the 710's, not sure why.

Fun tires.

[DJWorm]

Hoosier A6:
AutoX Concrete = 40F/36R cold starting pressures, then bleed back to 40/36 hot between runs.

AutoX Asphalt = 38F/36R cold, bleeding as above to 38/36.

Hoosier A6/R6
High speed track = 35F/33R cold to reach 38/36 hot. Only bleed to maintain hot pressures at 38/36

Dry Nitrogen fill.

You can run lower rear pressures when you need more rear trction IF you run stiffer bars and springs and proper suspension set up on. The MINIMUM rear tire pressure is = Total Car Weight (including driver and fuel load)/100

Run Rain tires +4 PSI all starting pressures.

For info see:
Hoosier Racing Tire - Tires Designed For Champions

If track or AutoX conditions (traction + pavement temp.) warrant we have run ranges between 44/40 and 36/32

[froggy47]

Thanks DJ

[outsideline]

04 z06 315 x 17 all around v710, nitogen fill auto x
I have run diffrerant pressures but have found mine work best @
28 frt 24 r. If the course is really hot, or on a road course, I will
increase up to 32 frt 28 rear. Have not yet tried the Hoosiers.