I have a 04 STI with stock BBS and pink springs, will the 245 be to big? Should i go with a 235?
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You should be fine.

I'm on RCE Blacks and I have Falken ZIEX 912 245/45/17's on my stock BBS and I have NO issues. The STI pinks give a similar drop.

If you are worried go 245/40/17.
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go with the 245/40. Im pretty sure the 245/45's will rub in the rear with people in the back seat or ish in the trunk. When I had JDM Pinks my rear was pretty low.
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rt-615 isn't an option in 245/40's. I'm sure they'd fit without any problems.
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^^^ skip the Falkens..

there are already Much better tires out there in the 245/40 size proven to work... better

Hankook R-S2
Bridgestone RE01-R
Dunlop Z1 (my preference)
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The Z1s run wide. On Luke's advice,I went with 235/45r17s on my 04 STi with Espilir GT springs,and it is a perfect fit. I don't think 245/45 would fit without rubbing.
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i have got Dunlop Dirtezza 245/45 R17 on stock suspension. Don't have any issuse. i think You will be fine with 245/45. my advice get 245/40 they look better on the car. 245/45 looks a bit to big.
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wouldnt 245 be kinda big? 04 sti came with 17x7.5 not 17x8..
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wouldnt 245 be kinda big? 04 sti came with 17x7.5 not 17x8..

True, but I'm pretty sure there are plenty of people running 255's on those wheels without problems.
It is a bit much tire to be squeezing on a 7.5'' wheel though.
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Are you an autocrosser? I have a 2004 STi on stock BBS wheels and RCE Tarmac 2 suspension. It is slightly lowered, but the 245-45-17 615's did not rub, but I will not be putting them back on the car. I run the REO1's (smae size) and love them. For those who have to buy the cheaper tire, I would go back to Hankook's RS2's (same size). I am a competitive driver, who finishes in the top ten in PAX (with great drivers such as DiSimo, Ruggles, San Nicholas, Litzul, to name a few), and I have been STU State Champ (FL) each year I have competed (this is my third season), but this is because Crash (Kornhaus) and other fast drivers stay out of SW Florida. The RS2's and I got along great, and down here I get them from Edgeracing for ~$106/tire. My camber and the 615's stiff sidewalls did not get along well. They wore out quickly. The REO1's wear good enough to of set the cost.
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