Square Setup 295 - 30 or 35 profile?!
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Joined: Apr 2022
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Square Setup 295 - 30 or 35 profile?!
Hello, I tried searching but couldn't find a definitive answer, sorry if my searching sucks (just shoot me a link).
I am currently running 295/35R18 square setup on my C5 Z06 track rat. While looking for the 2023 season I've noticed the tire options (and wallet) to be slim. When looking at options I noticed that some place (Apex Wheels for one) mentions that 295/30R18 is a good track setup and in my research offers up a few more tire options. For reference the stock rear size is 295/35R18. I might be splitting hairs here but the overall circumference and diameter are large enough to make a difference I'm sure (at least on the speedo).
Does anyone here run a 295/30R18 setup on the track? Would you all the smaller diameter here helpful or even noticeable?
Insight from the experienced is welcome. Thanks!
I am currently running 295/35R18 square setup on my C5 Z06 track rat. While looking for the 2023 season I've noticed the tire options (and wallet) to be slim. When looking at options I noticed that some place (Apex Wheels for one) mentions that 295/30R18 is a good track setup and in my research offers up a few more tire options. For reference the stock rear size is 295/35R18. I might be splitting hairs here but the overall circumference and diameter are large enough to make a difference I'm sure (at least on the speedo).
Does anyone here run a 295/30R18 setup on the track? Would you all the smaller diameter here helpful or even noticeable?
Insight from the experienced is welcome. Thanks!
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Joined: Jan 2019
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From: Somewhere, Florida
St. Jude Donor '20-'21-'22-'23-'24
I have a 305/30 square setup, so not EXACTLY yourr question, but I definitely noticed the difference in effective gear ratio from the smaller tire. It makes my cammed car a little happier cruising in 6th at lower speeds.
Assuming you have a base car that was originally equipped with 275/40-18 rears, your effective ratio goes from 3.42 to 3.65. You will notice it. If your car is a Z06, the difference from 295/35 to 295/30 is an effective gear ratio of 3.58.
EDIT: I didn't read, you said Z06. So ignore the first half of my math, but I'm keeping it up in case anyone else searches for this in the future lol
Assuming you have a base car that was originally equipped with 275/40-18 rears, your effective ratio goes from 3.42 to 3.65. You will notice it. If your car is a Z06, the difference from 295/35 to 295/30 is an effective gear ratio of 3.58.
EDIT: I didn't read, you said Z06. So ignore the first half of my math, but I'm keeping it up in case anyone else searches for this in the future lol
Thread Starter
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Joined: Apr 2022
Posts: 68
Likes: 13
I have a 305/30 square setup, so not EXACTLY yourr question, but I definitely noticed the difference in effective gear ratio from the smaller tire. It makes my cammed car a little happier cruising in 6th at lower speeds.
Assuming you have a base car that was originally equipped with 275/40-18 rears, your effective ratio goes from 3.42 to 3.65. You will notice it. If your car is a Z06, the difference from 295/35 to 295/30 is an effective gear ratio of 3.58.
EDIT: I didn't read, you said Z06. So ignore the first half of my math, but I'm keeping it up in case anyone else searches for this in the future lol
Assuming you have a base car that was originally equipped with 275/40-18 rears, your effective ratio goes from 3.42 to 3.65. You will notice it. If your car is a Z06, the difference from 295/35 to 295/30 is an effective gear ratio of 3.58.
EDIT: I didn't read, you said Z06. So ignore the first half of my math, but I'm keeping it up in case anyone else searches for this in the future lol
Racer
Joined: Nov 2020
Posts: 401
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From: Baltimore, MD
I've wondered the same thing. The 295/30 are even a touch smaller than the factory front tires. In the rear they are over an inch shorter than stock. How are the 295/35's on the front? Any rubbing? To make it even more confusing, 285/35 are an option, but not a lot of choices in that size. I'm also struggling to decide which way to go for my next set of track tires. It seems like most folks are running 315/30-18 square for their track setup. Right now I'm leaning toward the Spec Corvette tires.
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St. Jude Donor '09-'10-'11
A 295/30 is going to be the better option for tracking. The smaller sidewall will provide a more crisp turn in feel, and lower the gears a little for better acceleration (not super noticeable though). The shorter tire also offers more fender clearance as you start going lower.
Racer
Joined: Sep 2013
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From: Snohomish, WA
St. Jude Donor '21-'22-'23
I've wondered the same thing. The 295/30 are even a touch smaller than the factory front tires. In the rear they are over an inch shorter than stock. How are the 295/35's on the front? Any rubbing? To make it even more confusing, 285/35 are an option, but not a lot of choices in that size. I'm also struggling to decide which way to go for my next set of track tires. It seems like most folks are running 315/30-18 square for their track setup. Right now I'm leaning toward the Spec Corvette tires.
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Advanced
Joined: Apr 2022
Posts: 68
Likes: 13
I've wondered the same thing. The 295/30 are even a touch smaller than the factory front tires. In the rear they are over an inch shorter than stock. How are the 295/35's on the front? Any rubbing? To make it even more confusing, 285/35 are an option, but not a lot of choices in that size. I'm also struggling to decide which way to go for my next set of track tires. It seems like most folks are running 315/30-18 square for their track setup. Right now I'm leaning toward the Spec Corvette tires.
A 295/30 is going to be the better option for tracking. The smaller sidewall will provide a more crisp turn in feel, and lower the gears a little for better acceleration (not super noticeable though). The shorter tire also offers more fender clearance as you start going lower.
Starting this year, I am running 295/35-18 square using factory Z06 wheels (+58mm offset). I have noticed at full lock, I do rub the front wheel liner slightly (front edge at the crown). I also have it lowered about 1/2" on the factory bolts, FYI. I tried to heat the liner a bit to reform it slightly so that it doesn't rub however, that SMC (?) material doesn't move much with heat like plastic would. I will most likely purchase new tires mid-year and I too am debating the 35 vs 30 profile topic. The tire I'm interested in (Bridgestone RE71-RS) is offered in both profiles in 295-18 size so it may boil down to what's available when purchase time comes. I am interested in lowering my CG by ~1/2" though so maybe 30 profile it will be...??? Decisions, decisions...
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