Switching to Square Setup C5Z
Thread Starter
Racer
Joined: Oct 2020
Posts: 305
Likes: 65
From: Huntington, NY
Switching to Square Setup C5Z
Please forgive me for my search skills are weak on this site.
I’m switching to a square setup on my C5Z (Stock 18’s all around). I would like to be able to rotate them when needed.
I wasn’t able to come up with a unanimous decision. What size tire do you guys recommend for the street? I was thinking 295/30-18
I just wanted to make sure before I buy. Thanks in advance for your response(s)!!!
Erik
I’m switching to a square setup on my C5Z (Stock 18’s all around). I would like to be able to rotate them when needed.
I wasn’t able to come up with a unanimous decision. What size tire do you guys recommend for the street? I was thinking 295/30-18
I just wanted to make sure before I buy. Thanks in advance for your response(s)!!!
Erik
Burning Brakes
Joined: Jan 2021
Posts: 878
Likes: 738
From: SW Desert
Those 295s should work nicely. I run 315/30/18 on 10.5s with a slight bit of rub-a-dub on the front brake ducts but my car is mostly for track duty. Just be aware that switching from staggered to square can mess with the wheel speed sensor function and you'll need to select traction control "off" or "competitive mode" when driving aggressively.
Instructor
Joined: Apr 2019
Posts: 162
Likes: 55
From: Raleigh, NC
Those 295s should work nicely. I run 315/30/18 on 10.5s with a slight bit of rub-a-dub on the front brake ducts but my car is mostly for track duty. Just be aware that switching from staggered to square can mess with the wheel speed sensor function and you'll need to select traction control "off" or "competitive mode" when driving aggressively.
Pro
Joined: Oct 2020
Posts: 529
Likes: 197
From: Columbus, MS
I'm running that setup on my car. I get just the slightest rub on the inside of the fender near the brake duct, as well as the inside of the top of the fender right where the paint meets the black plastic, and they only make contact under heavy suspension load. I'm running -3 front camber, running a more "normal" street alignment might result in more rub.
Le Mans Master
Joined: May 2006
Posts: 7,835
Likes: 223
From: Hillsboro OR
I have been running 285x35x18 square on the track for 4 years now in my 03 (nowhere near stock) Coupe. Running square does not cause any warnings. You don't have to turn off the nannies either. I believe that the whole 1" delta tire spec is a maximum spec. A less than 1" delta. or square is OK. 
Pro
Joined: Oct 2020
Posts: 529
Likes: 197
From: Columbus, MS
I have been running 285x35x18 square on the track for 4 years now in my 03 (nowhere near stock) Coupe. Running square does not cause any warnings. You don't have to turn off the nannies either. I believe that the whole 1" delta tire spec is a maximum spec. A less than 1" delta. or square is OK.
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Drifting
Joined: Nov 2017
Posts: 1,385
Likes: 299
295/30/18 Yokohama AD08R tires on my 02 for track days. Never had any complaints from TC or AH.
But the AH will fight you on track when you're trail braking, so you might want to turn it off anyhow.
I've heard of people running 285/35/18 and 315/30/18 as well. Actual size sometimes varies from the advertised size, so you really have to look at the detailed specs to be sure.
But the AH will fight you on track when you're trail braking, so you might want to turn it off anyhow.
I've heard of people running 285/35/18 and 315/30/18 as well. Actual size sometimes varies from the advertised size, so you really have to look at the detailed specs to be sure.
Le Mans Master
Joined: Oct 2007
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From: Akron Ohio
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I run 285/30R18 on 18x11 Apex EC-7 wheels square for the track and 285/35R18 tires on 18x10.5 OE rear square on the street. I like the taller sidewall for street driving and avoiding road hazards. No issues, and like mentioned, just be sure not the turn the wheel all the way and it wont rub.
Thread Starter
Racer
Joined: Oct 2020
Posts: 305
Likes: 65
From: Huntington, NY
I installed General G-Max RS CL 295/30-18’s. The fronts look better, the rears look horrible. That’s the largest tire size they make in that tire.
Can I install a wheel spacer on the rears just to stick them out more to match the fronts? Probably need a 1/2”.
If anyone knows please let me know!
Can I install a wheel spacer on the rears just to stick them out more to match the fronts? Probably need a 1/2”.
If anyone knows please let me know!