Tire advice

[DRM500RUBYZR-1]

Originally Posted by EvanZR1

For standing mile events, you must run a tire that is speed rated for what speed you'll be running. Right now a Y rating (up to 186) would be fine as I ran 176MPH last fall. If I add 3.90/4.10 gears and/or a small nitrous shot, I could see potentially getting up to/over that, which means I'd need tires with a (Y) rating (over 186).

I absolutely get what everyone is saying and would agree that the tires aren't going to explode for a brief run over their rated speed, but once you move to standing mile, the event organizers have absolutely ZERO give in their requirements.

It probably really doesn't matter that much as even with better gearing I doubt I'd hit 186, 10MPH in the standing mile is a HUGE change. Having said that, I guess having to buy new tires would be a nice problem to have because the car was too fast.

Well said, Indeed!
Good luck with your tire purchase and your further mods!
Marty

[spork2367]

Originally Posted by EvanZR1

For standing mile events, you must run a tire that is speed rated for what speed you'll be running. Right now a Y rating (up to 186) would be fine as I ran 176MPH last fall. If I add 3.90/4.10 gears and/or a small nitrous shot, I could see potentially getting up to/over that, which means I'd need tires with a (Y) rating (over 186).

I absolutely get what everyone is saying and would agree that the tires aren't going to explode for a brief run over their rated speed, but once you move to standing mile, the event organizers have absolutely ZERO give in their requirements.

It probably really doesn't matter that much as even with better gearing I doubt I'd hit 186, 10MPH in the standing mile is a HUGE change. Having said that, I guess having to buy new tires would be a nice problem to have because the car was too fast.

Makes sense. While I'd agree that 186+ is ambitious, it looks like the Pirelli P Zero Rosso is going to be one of the only (Y) rated tires in the size range you're looking for, at least for rears. On the Corsa, the smallest rim size is a 19" and at that diameter, the widest tread width is 265.

[EvanZR1]

Corsa is available from Tirerack and Discount in 335/30R18 in a (Y) speed rating. Thinking about Rosso in front and Corsa in the rear.

[spork2367]

Originally Posted by EvanZR1

Corsa is available from Tirerack and Discount in 335/30R18 in a (Y) speed rating. Thinking about Rosso in front and Corsa in the rear.

Ah. Not the "Corsa," but the "Corsa System". Why name two different tires so similarly...

That looks like an awesome tire.

[EvanZR1]

Yeah, I used these on my supercharged 2013 GS in the rear, and they worked very well. Best of the "streetable" track tires I've ever used. Handled the 700rwhp in my GS pretty well, so thinking they should handle 391 motor's power pretty well.

[XfireZ51]

Evan,

There’s a standing mile HP calculator at the bottom of this page.

Just playing w some SWAG figures, u would need another ~ 100hp to jump 10mph in trap.

Give it a play:

https://www.rbracing-rsr.com/aerohpcalc.html

[EvanZR1]

Well 100HP is certainly doable, just throw a small nitrous setup on it.

[EvanZR1]

Originally Posted by XfireZ51

Evan,

There’s a standing mile HP calculator at the bottom of this page.

Just playing w some SWAG figures, u would need another ~ 100hp to jump 10mph in trap.

Give it a play:

https://www.rbracing-rsr.com/aerohpcalc.html

Interesting calculator, more of a potential top speed calculator, not standing mile as it doesn't account for gearing, but I've got a separate calculator for that. Looks like fully loaded (driver, fluids, roll bar, etc), with cd and frontal area for C4, I should actually be able to hit 200 with perfect gearing, since I should be over 600HP with the 391 engine can cams.

[USAZR1]

Evan, what 18" rear tires are your competitors running, for those speeds? I'm assuming you are running 335/30/18's, now. Still have a 3.45 rear gear?

[EvanZR1]

Yes, I'm on 335/30/18 rears, and still running the stock 3.45 rear gear. No real competitors in C4s that I've seen at the events I've been to. Most Vettes at these events are C6/7, with a few C5s, and almost no C4s.