[buckwam]

Looking at new performance all season tires and trying to decide if a staggered or square set up would provide the best handling on the street. I have a set of 18x8.5 and 18x9.5 wheels on a T4 camaro. A 255/40 would fit either wheel or could do 235/245 on front and 265/275 on back. With less power than a V8, would the wider tires up front provide better braking without the need for a wider rear to hook up? I assume I could not rotate the tires on a square set up due to different wheel offsets?

[2SS Capt]

I would go 245 up front and 275 in the rear and call it a day, you are correct, with the staggered wheel sizes you can't rotate...

[bishopts]

I agree with 245 and 275.

[arpad_m]

245 and 275 will be fine. You can go up to 255 and 285 on these 8.5" and 9.5" wheels if you want a slightly beefier look, I ran a setup like that for quite a while with zero issues.

As others pointed out, you will not be able to rotate with a staggered setup, only switch from side to side, which doesn't help much if any, so tread life will be affected significantly (as in, almost cut in half). Just something to keep in mind.

[buckwam]

Staggered it is. Tire Rack considers the Pirelli P zero AS Plus 3 a better warm/dry tire than the Continental Extreme Contact DWS 06+. Even calling it the driver's choice tire. The Continental edges out the Pirelli when snow and ice performance is considered. 265/35 is the widest Pirelli makes this tire in size 18. Continental makes the DWS 06+ in a 275/35. Would the wider size negate the Pirelli's warm weather performance since the test was done on equal size tires? Any other tire you would recommend over one of these?

[arpad_m]

Hm, I overlooked the fact that your wheels are still going to be 18".

When we mention "275/35" or "245/40", we typically mean 20" wheels, and your original size (245/50/18) is exactly the same as 275/35/20, so that kind of change upsets nothing. However, 265/35/18 or even 275/35/18 would be tiny compared to your original 245/50/18s, your speedo will be way off, if that setup even works (I never tried even when I had 18" wheels on a different 6th gen Camaro).

I strongly advise that you get tires with more sidewall, 40% at the very least but ideally 45, and Pirelli's sizing doesn't even come close. Overall, as far as I can see, quality 18" all-season tires don't come in the variety you need for a true staggered setup, likely because the intersection of the two buyer segments that want all-season tires and that want very wide sizes is almost zero.

So, I'd consider

• just staying square with better tires in your current size (245/50/18), which the Contis do come in, or
• getting proper summer tires instead of the all-season nonsense; for example, the Michelin PS4S does come in 255/45/18 and 285/40/18, which would be ideal for a staggered 18" setup, and it's a proper 3-season tire that you can use down to 34-35 degrees, dry or wet (not in the snow though)

[buckwam]

Is there any handling advantage in having the front and rear tires as close to the same overall diameter or is anything less than 3% difference acceptable? I would think a smaller front sidewall would benefit steering response and a slightly taller rear sidewall would benefit traction.

[arpad_m]

If you deviate from the original front-to-rear ratio by more than ~3%, ABS and Stabilitrak will become erroneous, which is the last thing you want.

You can try short sidewalls as long as you keep the above ratio difference under 3%, but then again, your car will be much lower to the ground, wheel gaps will be gaping (no nice lowered look), your speedo will read 60 mph when you're only doing ~55 mph unless you adjust tire sizes in the tune... a thousand little cuts IMO. But, at the end of the day, it's your car and your money