fwiw, my 17x9 +45 wheel gives me almost no clearance to the strut in the front. We're talking something like 6mm (next time i have the car in the air I can check that for you). According to tirerack a 255/40/17 mps4s is 9.1" wide while a 245 hoosier is 9.7". I fit a 245/40 DZ3 with some clearance, and that's an 8.8" tire. On a 9" wheel, I think a 245 hoosier won't exactly fit and you'd rub on the strut, but on an 8.5" wheel you might get away with 1mm or maybe 2 of clearance. I say this assuming both would be 45 offset, that the 8.5" wheel would sit exactly the same (meaning 0.25" narrower on inside and outside of the wheel), and that the inside and outside of the wheel have the slightly offset mounting. Visually it makes sense in my head, but do tell me if i need to explain it better, lol!
What's interesting is that your chart has the 255 a052 and 255 dz3 as similar width with the yoko being a touch narrower, but when i mounted my 235/45/17 yoko it was a touch wider than my 245/40/17 dz3. I know they're different sidewalls, but it's interesting.
So the main reason for posting was to see what is the largest 17” slick I can safely stuff under the fender. Was using Cliff’s experience with past and present wheel fitments as a guide.
My initial request for a 17” Apex wheel spec was for a 17x8.5 et 45.
Basically a middle of the road wheel size that could accommodate a range of track friendly tire sizes, without creating major fitment issues and negate the need for wheel spacers and be BBK friendly.
My RSE16 17x8.5 et45 fits With the 255-40-17 NT01’s. 8.8’ tread width and overall diameter of 25”. There is a little clearance to the front strut on the inside. On the rear it has rubbed the paint off the fuel filler guard. I’m assuming due to tire deflection under cornering.
I need to decide between:
17x8.5 et 45
or
17x9 et 45 (does this need to be an et40 offset?)
The biggest clearance issue is the right rear on the stock GTi. The R’s have a little extra wiggle room at the back. The R’s and regular GTi’s have the same front fender clearance from what I understand.
The 9” rim is better for a 245 to 265 tread-width tire, giving a better tread width contact patch, at possibly the expense of fitment issues. Cliff is running 18x9’s without any clearance issues on the front struts.
I noticed that there is a fair difference in tread width between the 35 profile 18” to the 40 profile 17”. The A052’s are similar, but there is a sizable difference between the RE71R’s.
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