Z06 Track tire sizes
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From: Waynesboro, Va
Z06 Track tire sizes
What tires are you guys going to run on the track? What tires for Autocross? Would it be worthwhile to drop to 18s for more sizes? Anyone running 295s or bigger up front?
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Joined: Feb 2023
Posts: 78
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From: SoCal
With a holistic view, are you also planning to increase the rear tire size to maintain the corning balance of the chassis?
I'm assuming you have the correct camber for the tires and you're springs are mated front to rear as a set.
(what springs and tires are on the car now?)
With the above settings correct, illusive balance must be chased by other means and just increasing tire sizes may not be the answer.
Welcome to the world of endless chassis adjustments and turning.
Is your goal increasing the front tire width to reduce understeer? If understeer is the issue, you could soften the front swaybar, or
stiffening the rear bar settings. Either of which would less expensive than a set of front tires.
From my experience, my LT1 and the Ron Fellows LT2 Z51 Stingrays are too soft for on-track play and both have a bit of understeer.
Now the Biggest conundrum: do you want a track-car with stiff springs or a comfortable street-car? One car cannot be both and the question of
enduring a track-stiff ride on the street, arises.
In the final assessment: it is most important to get the on-track tire temps hot enough to reach their optimum adhesion window. I build a 914 with a 383 Chevy track car: 475 HP with a 2550 weight. I mounted 245 mm fronts and 315 mm rears. It look awesome....But, I could never get the tires hot enough to work
at Willow Springs in 100 degree heat. My tire temps were never more than 130 deg. while their "happy region" was 160 to 200. The tires were too wide to create
slip-angles and heat up. Maybe, after running minimal toe, front & rear, I should have cranked in big toe-in to induce scrub.
Chassis tuning is a complex challenge, but it's great to start with the well developed stingray chassis.
I hope I'm being helpful, Terry
I'm assuming you have the correct camber for the tires and you're springs are mated front to rear as a set.
(what springs and tires are on the car now?)
With the above settings correct, illusive balance must be chased by other means and just increasing tire sizes may not be the answer.
Welcome to the world of endless chassis adjustments and turning.
Is your goal increasing the front tire width to reduce understeer? If understeer is the issue, you could soften the front swaybar, or
stiffening the rear bar settings. Either of which would less expensive than a set of front tires.
From my experience, my LT1 and the Ron Fellows LT2 Z51 Stingrays are too soft for on-track play and both have a bit of understeer.
Now the Biggest conundrum: do you want a track-car with stiff springs or a comfortable street-car? One car cannot be both and the question of
enduring a track-stiff ride on the street, arises.
In the final assessment: it is most important to get the on-track tire temps hot enough to reach their optimum adhesion window. I build a 914 with a 383 Chevy track car: 475 HP with a 2550 weight. I mounted 245 mm fronts and 315 mm rears. It look awesome....But, I could never get the tires hot enough to work
at Willow Springs in 100 degree heat. My tire temps were never more than 130 deg. while their "happy region" was 160 to 200. The tires were too wide to create
slip-angles and heat up. Maybe, after running minimal toe, front & rear, I should have cranked in big toe-in to induce scrub.
Chassis tuning is a complex challenge, but it's great to start with the well developed stingray chassis.
I hope I'm being helpful, Terry
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