95 ///M - Can I put 245/40/18 rubber all around?

[trahsub]

I have 18x8 BBS RX wheels and would like to run 245's all around. Can I do so without rubbing? I'm lowered on H&R coils, not a crazy drop though.

[Ace M3]

You MIGHT have to run spacers, or you MIGHT have to roll your fenders. It all depends on your offset. My guess would be at least a roll.

[SG_M3]

you'll want 245/35's for the correct overall diameter.

[trahsub]

I have 18x8 BBS RX wheels and would like to run 245's all around. Can I do so without rubbing? I'm lowered on H&R coils, not a crazy drop though.

I think the offset might be 38..?

[Tremelune]

245/40 will be closer to the stock rolling radius: http://www.carbibles.com/tyre_bible_pg2.html

You want to find out the offset of your wheels. It is the largest unknown contributing factor to your rub-or-no-rub question.

[Vonbimmer]

Hard to say, as other stated. I had 245/40/17's on my 95 when it was on stock suspension and nothing rubbed, but I went to the stock size once I lowered it just in case.

[m3jones]

245/40 will be closer to the stock rolling radius: http://www.carbibles.com/tyre_bible_pg2.html

You want to find out the offset of your wheels. It is the largest unknown contributing factor to your rub-or-no-rub question.

Stock radius is 12.2". 245/40/18 radius is 12.9". 245/35/18 radius is 12.4".

Offset is obviously much more important, but 245/35 is a better choice than 245/40 for 18" wheels.

[stanksbeamen]

Stock radius is 12.2". 245/40/18 radius is 12.9". 245/35/18 radius is 12.4".

Offset is obviously much more important, but 245/35 is a better choice than 245/40 for 18" wheels.

Why is that? Depending on how much power he has and if traction is any issue i thought you want to get as much in there as possible for grip. But he didnt say anything about that subject... Well im runnin 245/40/17 and im on GC coilovers and they barely fit. I have 10 mm spacer upfront also. Good luck.

[Devius1]

offset.... pure offset. I run 245/265 no spacers F/R. 3pc. wheels assembled to fit though.

[Tremelune]

Stock radius is 12.2". 245/40/18 radius is 12.9". 245/35/18 radius is 12.4".

Offset is obviously much more important, but 245/35 is a better choice than 245/40 for 18" wheels.

Oops, you're absolutely correct. My calculations were for 17" wheels.

[Tremelune]

Why is that? Depending on how much power he has and if traction is any issue i thought you want to get as much in there as possible for grip.

Well, it's a bit trickier than that. Lower profile tires will squirm less and feel a bit "tighter". My terms are incorrect, but essentially, with taller tires, there's more room for the rubber to move around when you change direction which can add to a bit of a sloppy feeling.

40 is low-profile. 35 is very low-profile.

The debate we were having was with regard to rolling radius. If you deviate too far from the stock radius too much your speedo/odo can be off by a significant amount...Your final gearing will also change. You'll see what I mean if you visit that link and scroll down to the calculator thing. When in doubt, stay as close to stock as you can.

[hinzm3]

I run 245/35/18 fronts and 255/35 rears. You can fit 255s up front if you wanted to

[Tremelune]

I run 245/35/18 fronts and 255/35 rears. You can fit 255s up front if you wanted to

What offset do you have going on?

[hinzm3]

What offset do you have going on?

I think they are 38mm I have 10mm spacers up front

[bennyfizzle]

On 18x8 et38 wheels I ran 255/35 PS2's with no spacers, only rubbed over harsh bumps in the front, on the fender lip. If you rolled the fender even slightly I would have never rubbed.

So in short, yes.

A friend of mine who had the same wheels ran 245/35 Goodyear F1's with absolutely no issues.

He's dropped on Eibach pro kit/bilsteins I believe, I'm on H&R coilovers on full slam up front.

Here's a few pics to show how flush it sat:

http://img.photobucket.com/albums/v225/bennyfizzle/M3%20pics/newwheels010.jpg

http://img.photobucket.com/albums/v225/bennyfizzle/M3%20pics/newwheels002.jpg

Fat ass:

http://img.photobucket.com/albums/v225/bennyfizzle/M3%20pics/newwheels006.jpg

:)

[trahsub]

Thanks guys. I eneded up going with new wheels. I got SSR Comp C's, ET44. I have 10 mm spacers up front and am going to run 245/40/17. I think I should be good. They are in my garage ready to be installed so I will let you know how it works out.

[bennyfizzle]

Just to let you know, speaking from experience, the best all-around tire size IMO for these cars is the a nice sticky factory recommended 235/40/17.

[trahsub]

Just to let you know, speaking from experience, the best all-around tire size IMO for these cars is the a nice sticky factory recommended 235/40/17.

I'm close to that. Square 245/40's all around. I'm anxious to see how these Direzza Star Specs perform. They look and feel the part. . .