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Maximum Wheel and Tire Width Fitment Guide for the FD

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Old 04-16-18, 11:11 AM
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Originally Posted by JazzyFD View Post
Hey guys I recently picked up some SSR Long Champ Vip Wheels from my buddy Circuit Theory. I need some help with tire sizing for a stockish 3rd gen. The wheel specs are 18x8 fronts 18x9 rears all with a +35 offset. And suggestions on tire sizing and Fitment would be greatly appreciated.
225/40-18 up front is best fit on wheels and for wheel lip and fender liner clearance. In back you may have some options, but 235/40-18 looks like the best bet there. 245/40-18 could work, but significantly taller. 245/35-18 could work but then you'd have front tires bigger in diameter than rears, which looks goofy... 255/35-18 might work, but getting kinda wide on +35 if fenders aren't rolled. Some negative camber would help there.
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Old 04-16-18, 01:06 PM
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If you're going to decrease the offset save yourself the hassle....roll the front fenders. I had 17 x 8 +34 wheels, with 235 x 45 x 18 tires, (stock is 16 x 8 +50 with 225 X 50 x 16 tires). the FD was lowered about 3/4 inch. Backing out of a driveway caught a fender....not good!

Rolled front fenders = peace of mind.
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Old 04-16-18, 01:38 PM
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If you're going to decrease the offset save yourself the hassle....roll the front fenders. I had 17 x 8 +34 wheels, with 235 x 45 x 18 tires, (stock is 16 x 8 +50 with 225 X 50 x 16 tires). the FD was lowered about 3/4 inch. Backing out of a driveway caught a fender....not good!

Rolled front fenders = peace of mind.


+1

Front fender lip roll is easy to do without messing up your front fenders.

One catch of the unrolled front fender lip on the tire can lead to damage that can't be undone as it kinks the sheetmetal.
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Old 04-16-18, 02:05 PM
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Originally Posted by Greg Sabol View Post
If you're going to decrease the offset save yourself the hassle....roll the front fenders. I had 17 x 8 +34 wheels, with 235 x 45 x 18 tires, (stock is 16 x 8 +50 with 225 X 50 x 16 tires). the FD was lowered about 3/4 inch. Backing out of a driveway caught a fender....not good!

Rolled front fenders = peace of mind.
235/45-18?! That's about 1 1/2" taller than stock! And you were lowered 3/4", no wonder you caught a fender... I think that 225/40-18 (stock width and diameter) on +35 should clear unrolled fenders, especially with some negative front camber dialed in which IMO is a good idea for handling anyway.
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Old 04-16-18, 02:24 PM
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Originally Posted by ZDan View Post
235/45-18?! That's about 1 1/2" taller than stock! And you were lowered 3/4", no wonder you caught a fender... I think that 225/40-18 (stock width and diameter) on +35 should clear unrolled fenders, especially with some negative front camber dialed in which IMO is a good idea for handling anyway.
You missed the info......they where 235 x 45 x 17's not 18's....Like Blue said....it's easy to roll the front fenders and doesn't mess anything up .....one curb or driveway turn-in and it'll cost much more to fix a front fender.

I've got 18 x 8 +40 with 18 x 35 x 255 fronts.... rolled front fenders....no problems.
18 x 9.5 +40 with 18 x 35 x 275 rears, rear fenders not rolled.

This set-up kept the rolling diameter close to stock.

Last edited by Greg Sabol; 04-16-18 at 02:25 PM. Reason: added info
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Old 04-16-18, 03:28 PM
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Originally Posted by Greg Sabol View Post
You missed the info......they where 235 x 45 x 17's not 18's....
I didn't miss it where you said "235 x 45 x 18 tires"! I did miss it where you said 17x8 wheels...

Like Blue said....it's easy to roll the front fenders and doesn't mess anything up
It often results in distorted/deformed wheel openings. Mine were professionally done by a good body shop and they're still not perfect.

.....one curb or driveway turn-in and it'll cost much more to fix a front fender.
Well, I was running 255/40-17s on +40 offset with very little camber, at 24.75" front ride height, I did tweak both unrolled front fender lips very slightly, no real damage. So I had them rolled. 225/45-17 tires have the same sidewall height but are 30mm narrower, so tire is 15mm further from the fender lip. Subtract 5mm for +35 offset vs. my +40 offset and you have a whopping 10mm more clearance than I had. That's plenty, should never touch the fenders at normal ride heights, particularly with some negative camber (like -1 or more negative).

I've got 18 x 8 +40 with 18 x 35 x 255 fronts.... rolled front fenders....no problems.
18 x 9.5 +40 with 18 x 35 x 275 rears, rear fenders not rolled.
I wouldn't run 255/35-18 on 8" wheels anyway... 225/40-18 would be a better fit on the wheel and give +15mm more clearance to the fender lip.
For the 17x8 +35 and 18x8 +35 front wheels kensin and JazzyFD have, I'd go 225 tires (225/45-17, 225/40-18) and not bother with rolling fenders.
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Old 04-16-18, 04:59 PM
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Originally Posted by ZDan View Post
225/40-18 up front is best fit on wheels and for wheel lip and fender liner clearance. In back you may have some options, but 235/40-18 looks like the best bet there. 245/40-18 could work, but significantly taller. 245/35-18 could work but then you'd have front tires bigger in diameter than rears, which looks goofy... 255/35-18 might work, but getting kinda wide on +35 if fenders aren't rolled. Some negative camber would help there.
With that suggestion will the tire maintain a meaty look. I would like a tall sidewalk that matches front to back.
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Old 04-16-18, 07:50 PM
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Originally Posted by JazzyFD View Post
With that suggestion will the tire maintain a meaty look. I would like a tall sidewalk that matches front to back.
Best fit and sidewall height match on 18x8 fronts and 18x9 rears is 225/40-18 fronts with 255/35-18 rears, which I *think* should fit in back with unrolled fenders, but again, negative camber helps and is a good idea anyway for handling. Very close on sidewall heights, BUT check the dimensions for the specific tire you're choosing. Just noticed that Hankook RS4 225/40-18 is much taller than others for some weird reason... *IF* you ran RS4s, you would want 245/40-18 rears to match the sidewall height of 225/40-18 fronts.
Tire Rack website has dimensional data on most tires, check there to be sure.
What kinda tires are you considering, and for what usage?
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Old 04-16-18, 08:19 PM
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Originally Posted by ZDan View Post
I didn't miss it where you said "235 x 45 x 18 tires"! I did miss it where you said 17x8 wheels...

It often results in distorted/deformed wheel openings. Mine were professionally done by a good body shop and they're still not perfect.

Well, I was running 255/40-17s on +40 offset with very little camber, at 24.75" front ride height, I did tweak both unrolled front fender lips very slightly, no real damage. So I had them rolled. 225/45-17 tires have the same sidewall height but are 30mm narrower, so tire is 15mm further from the fender lip. Subtract 5mm for +35 offset vs. my +40 offset and you have a whopping 10mm more clearance than I had. That's plenty, should never touch the fenders at normal ride heights, particularly with some negative camber (like -1 or more negative).


I wouldn't run 255/35-18 on 8" wheels anyway... 225/40-18 would be a better fit on the wheel and give +15mm more clearance to the fender lip.
For the 17x8 +35 and 18x8 +35 front wheels kensin and JazzyFD have, I'd go 225 tires (225/45-17, 225/40-18) and not bother with rolling fenders.
thank you so much for the information.
my wheels are 17x8 +35 and 17x9 +38
Not 18s lol. But i get the point tho

so 225 40 17 front with -camber and 255 40 17 in the rear
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Old 04-17-18, 09:23 AM
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Originally Posted by kensin View Post
thank you so much for the information.
my wheels are 17x8 +35 and 17x9 +38
Not 18s lol. But i get the point tho
so 225 40 17 front with -camber and 255 40 17 in the rear
225/45-17 front with 255/40-17 rear for same sidewall height, stock tire diameter.
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Old 04-17-18, 02:30 PM
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Hi Guys,

I'm going to be purchasing some wheels in the following sizes

​Front - 18x9.5 +45
Rear - 18x10 +40

What are the max tire sizes I can run for the front and rear? I was thinking either 275/40/18 or 285/35/18 Rear but I don't have a clue about the front. I don't mind rolling the fenders a little but certainly no pulling etc

I'm looking at a few tires but the Michelin Super Sport and the Continental Extreme Sport are looking like winners at the moment.

Last edited by 7_rocket; 04-17-18 at 02:51 PM.
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Old 04-17-18, 04:39 PM
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Originally Posted by ZDan View Post
225/45-17 front with 255/40-17 rear for same sidewall height, stock tire diameter.
if im retaining stock diameter and side wall height, wont it rub on the front since i got +35 offset ?
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Old 04-17-18, 06:30 PM
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Aggressive 17 in set up that will NOT fit Stoptech brakes.
17x9 +45 Front
17x10 + 38 Rear
Just to confirm, will this fitment require rolled fenders? Car will be on coilovers.


Looking for atleast 9" on front and 9.5 on the rear. Was just wondering how far you can push it out on unmodified fenders.
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Old 04-17-18, 07:17 PM
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Originally Posted by ZDan View Post
Best fit and sidewall height match on 18x8 fronts and 18x9 rears is 225/40-18 fronts with 255/35-18 rears, which I *think* should fit in back with unrolled fenders, but again, negative camber helps and is a good idea anyway for handling. Very close on sidewall heights, BUT check the dimensions for the specific tire you're choosing. Just noticed that Hankook RS4 225/40-18 is much taller than others for some weird reason... *IF* you ran RS4s, you would want 245/40-18 rears to match the sidewall height of 225/40-18 fronts.
Tire Rack website has dimensional data on most tires, check there to be sure.
What kinda tires are you considering, and for what usage?
Honestly I want to run Falken 615k+ or Continental Extreme Contacts
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Old 04-18-18, 09:16 AM
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Originally Posted by kensin View Post
if im retaining stock diameter and side wall height, wont it rub on the front since i got +35 offset ?
I run 255/40-17 on +40 offset, which puts my tire's sidewall 10mm closer to the fender lip vs. 225 on +35. I *barely* tweaked the unrolled fender lips while running very little camber (-0.5 IIRC). With 10mm more clearance, you should be OK even with modest camber (but I'd still run at least -1 for handling). Again, 255/40-17 are the same diameter, same sidewall height as 225/45-17.
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