I was looking for 15x7 wheels for my car, and instead got a deal on some scratched/gouged/generally ugly 17x7 wheels. Refrigerator paint will fix that right up, and 17" tires are easier to find nowadays than 15", right?
The only problem is, I don't know what size tires to run. I have a somewhat traction limited rear drive and this shades me to want to run the 215/40 for more footprint. But, that is running right out at the minimum recommended rim width, which I don't like, which makes me consider the 205/45.
That is approximately the diameter I want to run. Bonus criteria: Looking for ultra performance summer tires under about $100 a pop. Use is street driving, autocross, maybe a track day or two.
205s would probably be considered "right" for that size wheel.
Personally, I prefer slightly narrower than right to get an effectively stiffer sidewall, but I'm not sure what you're going to find in a high-performance tire for a 17" rim that's that narrow.
Tirerack apparently has Yokohoma S Drives in 195/45R17 for $92/piece, for what that's worth.
HEAT.......... MASS
footprint is fine, but when it comes to real handling... you want to build heat. depending on the mass of your car... a 205 might actually handle better on the track because you can get it up to a proper heat....
Tire heat is no problem, the car is not particularly light, and I have a reputation for overdriving the car a wee bit.
I currently run 225 width tires on 15x7 and I'd like to see even more, but at some point there's only so much my wallet can provide, and 245-width tires get to be an expensive consumable.
195/45 would be incredibly short for me!
My opinion is that 225 is just too wide for a 7" rim. Most cars that come factory equipped with 245s do so with 8" rims. If you want wider tires, you need wider rims to mount them on, plain and simple.
What bolt pattern are you working with?
ReverendDexter wrote:
My opinion is that 225 is just too wide for a 7" rim.
That's what scads of Mustangs had from the factory.
Most cars that come factory equipped with 245s do so with 8" rims. If you want wider tires, you need wider rims to mount them on, plain and simple.
That's why I have the dilemma between 215/40 and 205/45. More treadwidth or more sidewall stability?
What bolt pattern are you working with?
4x114.3, truly an orphaned size. I'm changing out from 4x110, thus why my current wheels are no longer useful.
My first thought before diving in to this project was to grab scratched/gouged/ugly wheels from 240SX drifters. Little did I know that most of them convert to 5 lug before getting Big Fat Wheels.
Knurled wrote:
ReverendDexter wrote:
My opinion is that 225 is just too wide for a 7" rim.
That's what scads of Mustangs had from the factory.
Scads of Mustangs that weren't exactly known for handling prowess, hahaha.
Tire compound is going to a bigger difference.
Just get the Dunlop Star Spec in 215/40, I think that's what I'm going to put on my E30.
ReverendDexter wrote:
My opinion is that 225 is just too wide for a 7" rim. Most cars that come factory equipped with 245s do so with 8" rims. If you want wider tires, you need wider rims to mount them on, plain and simple.
What bolt pattern are you working with?
I have 225s on an 8 inch wide wheel. The wheels are on the slightly wide side of ok. I have run 205s on 8 inch wheels and the wheel is wide enough that the wheel lip is exposed. 225s work just fine and fit nicely on 7 inch wheels.
ReverendDexter wrote:
Scads of Mustangs that weren't exactly known for handling prowess, hahaha.
I'm sure the tire/wheel relationship had little to do with it, in light of the absolutely horrid suspension geometry at both ends.
I'd love to have the Star Specs, but they're out of my price range. I was thinking of the G Force Sports or regular DZ101s.
The Sumitomo HTR Z looks tempting, but the ones I drove on a Formula 350 felt like greased peanut butter.
z31maniac wrote:
Tire compound is going to a bigger difference.
My thoughts exactly. Get the best tires, not necessarily the biggest tires.
Discount Tire has 215/40 RT-615s for $103 a pop, and an $80 rebate if you buy four before some date in April.
Decision's made 
Thanks guys.
ReverendDexter wrote:
Knurled wrote:
ReverendDexter wrote:
My opinion is that 225 is just too wide for a 7" rim.
That's what scads of Mustangs had from the factory.
Scads of Mustangs that weren't exactly known for handling prowess, hahaha.
Funny how many Mustangs have won AS...
In reply to John Brown:
Despite my signature, I'm not on the "Mustangs = crap handling" bandwagon.
I like my Mustangs. I'm sad I just had to get rid of my Cobra. I'm attempting to make an automatic 5.0 convertible a force to be reckoned with at my local autocross (yes, I'm aware I'm totally delusional, but we have LOOSE classing... all they care is that I have a V8 and if my treadwear is under 140).
I just think 225 is too wide for an 7" rim. It's 126% of the rim width, and my understanding is 110-115% is ideal, and 125% is as big as you want to go. Maybe my numbers are wrong, or don't take something important into consideration?
ReverendDexter wrote:
I just think 225 is too wide for an 7" rim. It's 126% of the rim width, and my understanding is 110-115% is ideal, and 125% is as big as you want to go. Maybe my numbers are wrong, or don't take something important into consideration?
Something VERY important: aspect ratio.
A 225/50 is just about right for a 7", in my opinion. Maaaybe a 7.5" would be better, more than that and you start stretching the tire (which may be what you're after for more response)
A 225/40, or even a 225/45, will require effort to get mounted on a 7" rim.
A 225/75 would look ridiculously stretched.
Mind you, the 225 is not the treadwidth, it is the total width of the tire on an arbitrary rim size (I forget how they determine that.) As the aspect ratio gets lower, the tread width tends to get wider as the tire gets more squared off.
I run 235/45s on 17x7.5 rims on my Ti.. they look "just right"
Knurled wrote:
Mind you, the 225 is not the treadwidth, it is the total width of the tire on an arbitrary rim size (I forget how they determine that.) As the aspect ratio gets lower, the tread width tends to get wider as the tire gets more squared off.
If you look at the spec sheets for a tire, they'll tell you what the width of the wheel used for the measurements is. No idea how it's chosen, but it's easy to check for a particular tire.
So, a funny thing happened between then and now...
I'm now thinking I need 275/50 tires, if only they made such a beast in a decently cornering tire. (And I could find 15x10 wheels cheaply enough)
Bridgeport is not just a city
