the new tire test fitment was semi successful

[Devious27t]

I need spacers in the rear to clear the upright in the rear (duh) but the good news is that it should be fine with a 3mm there. I think the new tires give it a much more aggressive stance. Also, yes I know I need to finish rolling the front fenders :-) Probably going to roll the rears too

[Squarrl]

Are those VMR VB3?

[Devious27t]

Are those VMR VB3?

they are Work Ryver FR's. Ultra rare in 5x112 fitment and very very old school. I had them refinished in black as when I got them, the silver wasn't doing it for me.

[onemoremile]

Nice. Are you running the same size all the way around?

[Devious27t]

Nice. Are you running the same size all the way around?

I am running staggered tire size and offset.

Fronts are 245/40 ET32 on an 18x8

Rears are 255/35 ET38 on an 18x9

Oddly enough I was running 225/245 stagger before and the turn in and rotation was better than any other quattro car i have driven to date. Get the keyboard tuners to explain that one

[audispeed]

could you do me a favor and actually measure the width of the tire? i am debating some 255's as an autocross tire but am not quite sure if they will fit. the reason i ask you to measure is i have had tires that actually measure up 20 mm narrower than the claimed with. if your tires are a legit 255 i will go ahead and get some. thanks.

[djwimbo]

could you do me a favor and actually measure the width of the tire? i am debating some 255's as an autocross tire but am not quite sure if they will fit. the reason i ask you to measure is i have had tires that actually measure up 20 mm narrower than the claimed with. if your tires are a legit 255 i will go ahead and get some. thanks.

In the fronts, you're not going to be able to fit 'em. At least not without modifications. At that wide your suspension movement will put the tire into the fender.
feel free to try, but I would think otherwise.
A 235/40 will fit w/o issues, and you can get a real sticky tire in that size.

[onemoremile]

235/40-17 is an easy fit and 245/40-17 isn't bad.

[Devious27t]

In the fronts, you're not going to be able to fit 'em. At least not without modifications. At that wide your suspension movement will put the tire into the fender.
feel free to try, but I would think otherwise.
A 235/40 will fit w/o issues, and you can get a real sticky tire in that size.

with a staggered offset and some hefty rolling, the front would actually be easier to fit IMHO. 245s are absolutely no problem with the offsets I am running.

[audispeed]

any chance you could get a measurement on the 255's for me? djwimbo and onemoremile, I am looking to run 245 or 255/40 r17 which (255) would be roughly equivalent to his 255/35 r18.

[Devious27t]

any chance you could get a measurement on the 255's for me? djwimbo and onemoremile, I am looking to run 245 or 255/40 r17 which (255) would be roughly equivalent to his 255/35 r18.

i ran around with a set of 255/17s on for about a month on my old car and they fit no problem. My suspension setup was full H&R sport and H-sport sways and had zero rubbing under any cornering condition. They were mounted on a set of the 5 spoke 17" B6 sport wheels. i will get the width today for you.

[djwimbo]

any chance you could get a measurement on the 255's for me? djwimbo and onemoremile, I am looking to run 245 or 255/40 r17 which (255) would be roughly equivalent to his 255/35 r18.

For comparison.
Toyo RA1 235/40R17 has an "overall" width of 9.6, vs the same tire in a 255/40 is 10.4. Their website doesn't specify tread width. I just measured my 235/40R17's @ ~8.8", but they are not mounted.
Falken Azenis which I've used, as opposed to the RA1's I have, but haven't mounted and balanced yet. I used a 225/45R17 have an overall width of 8.9 and a tread width of 8.3". A 255/40R17 Azenis measure 10.3" and 9.4".

I'm sure with some spacers and heavy fender rolling you can stuff something big under there, but it's also limited on how low you want to go as well.
Low does not mean fast. You are supposed to have suspension travel.

Just remember the more you change tire and wheel sizes to more you mess with a "factory tuned" suspension. Going much lower than stock sport height may not give you an advantage.
Look up some of the posts by "onemoremile" if you want to learn about suspension stuff. He knows what he's talking about.

[audispeed]

For comparison.
Toyo RA1 235/40R17 has an "overall" width of 9.6, vs the same tire in a 255/40 is 10.4. Their website doesn't specify tread width. I just measured my 235/40R17's @ ~8.8", but they are not mounted.
Falken Azenis which I've used, as opposed to the RA1's I have, but haven't mounted and balanced yet. I used a 225/45R17 have an overall width of 8.9 and a tread width of 8.3". A 255/40R17 Azenis measure 10.3" and 9.4".

I'm sure with some spacers and heavy fender rolling you can stuff something big under there, but it's also limited on how low you want to go as well.
Low does not mean fast. You are supposed to have suspension travel.

Just remember the more you change tire and wheel sizes to more you mess with a "factory tuned" suspension. Going much lower than stock sport height may not give you an advantage.
Look up some of the posts by "onemoremile" if you want to learn about suspension stuff. He knows what he's talking about.

Trust me, I am not of the "lower is better" mantra. My car is set up at a good compromise ride height right between good road/track performance and getting in and out of my parking garage.

As far as tire width, I only ask because I have two sets of 225/40/18 one of which measures tread width of ~ 8" (falkens, closer to 205 mm) and the other of which measures 9" (kuhmos - and approximately 225 mm). Just trying to figure out if a genuine 255 tire will fit.

Thanks for the tread info. That will be helpful in selecting tires in the future. why can't a 225, 235, or whatever tire actually measure out as claimed

[djwimbo]

Trust me, I am not of the "lower is better" mantra. My car is set up at a good compromise ride height right between good road/track performance and getting in and out of my parking garage.

Thanks for the tread info. That will be helpful in selecting tires in the future. why can't a 225, 235, or whatever tire actually measure out as claimed

I'm glad there's other people that understand that.

The rating of the "225" or "255" is the section width. It's the widest point of the tire. Typically this includes the "rim lip protector". Almost all tires have some curve in the sidewall. My 225/45R17 Azenis didn't have much at all, but still some. This also depends on the wheel width compared to the tire width.
You can't cram a 225 on a 9" wide wheel and make the contact patch any larger either.

The rating of the tire is in basic terms. Nothing is really set in stone. My Cooper Zeon ZPT 245/50R16 on my Camaro were almost 3/8" wider than my friends 255's on his Acura. It really just depends on the tire company's design.

[onemoremile]

245/40-17 Yoko Guardex on the left, 225/50-16 Sumitomo HTR 50Z on the right. The level is flat on the Yokos and less than 1/4" off the Sumis.




Track tires are a different animal since they are usually shaved. This removes the tread and reduces the overall diameter which helps with clearance. This also serves to lower the car a bit without messing up the suspension geometry. I don't see a problem with running a 255/40-17 or 255/35-18 on an 8.5" wheel. With the right offset it would fit easily. A brand new street tire would be a much harder fit.

[Devious27t]

245/40-17 Yoko Guardex on the left, 225/50-16 Sumitomo HTR 50Z on the right. The level is flat on the Yokos and less than 1/4" off the Sumis.




Track tires are a different animal since they are usually shaved. This removes the tread and reduces the overall diameter which helps with clearance. This also serves to lower the car a bit without messing up the suspension geometry. I don't see a problem with running a 255/40-17 or 255/35-18 on an 8.5" wheel. With the right offset it would fit easily. A brand new street tire would be a much harder fit.

I finally got off my ass and calc'd my ratios to find that there is only a 2.7% difference between my 245/40's and the 255/35's which is within the 3% spec listed for quattro cars.