TMitchell

What is the widest tire anyone here has mounted on the stock 17" x 8 wheels? I know that 265x40-17" are just about the same diameter as the 235x45-17", but they recommend 17 x 9 wheels or wider for the 265s. I figure that the 265s would fill my rear wheel wells better, without having to get a new set of 18 or larger wheels. I notice that some suv's run this width on just 8" wide wheels. What is the downside of doing this?

bitkahuna

iTrader: (20)

If your goal is to fill the wheel wells better, wider tires isn't the way to go because the rims will still look so inset.

I have 265s on 9.5" rears and I'm told I'm ok putting a 275 but that's it. From everything I've heard I'd never put a 265 on an 8" rim. 265mm = 10.4" so that's a lot of overhang on an 8" rim. I haven't even heard of anyone doing a 255!

RocketSlug

I have a gs430 with 255/40/17's on my rear stock 17x8's. Almost no overhang, and almost imperceptible wheel well filling. I am going to try to take them back and see if I can get 265/40's. I bought H-rated DiscountTire Rage tires to tear up at the drag strip, and I wanted more BMW-like overhang than I got. Back in the days 5-10 years ago, on 3's and 5's, BMW put a tire on 2 sizes too wide and tall for the wheels, and it had a powerful look to it, like tires that wide were needed to control the power.

But the stock 17x8s are holding my 255/40/17's in the rear with no problems. This comes unfortunately, because I wanted them to look different. They are 1.16% faster spinning, contributing to 1700 more miles per 10000 miles driven. 255/45 will also fit and save you mileage on the odometer, but the 255/40's lower my gear ratio a bit, and I'm anxious to see what it will do on the track. I am only going to keep them on during drag season, which ends 11/01 here in Ohio.

GS4Will

Hey rocket,

thanks for the detailed info.

mind analyze the diff(if any) on the odometer or any other factor, of choosing 245/40/18+275/35/18, versus 245/40+285/35

based on my calculation, the 1st combo is the closest to the original 225/55/16.

thanks a lot.

william

TMitchell

[QUOTE]Originally posted by gs4will
[B]Hey rocket,

thanks for the detailed info.

mind analyze the diff(if any) on the odometer or any other factor, of choosing 245/40/18+275/35/18, versus 245/40+285/35

based on my calculation, the 1st combo is the closest to the original 225/55/16.


http://www.powerdog.com/tiresize.cgi

You can find the info you need on this site

GS4Will

TM,

thanks for the info.

GSman

iTrader: (2)

Rocketslug,

Will the 255/4017 also fit on the front without rubbing? What size tire will you switch back to after the season?

TMitchell

I would keep the 235/45x17 on front and put 265/40x17 on back, if I could. It is too bad you can't order 17" factory chromes in 9 or 9 1/2" widths. If that was possible I would order 2 and leave the front and spare as is.

paulcars

RocketSlug's information was great. The difference in 10,000 miles is only 170 miles not 1700 at 1.7% as stated. Those darn decimals!!

///MDex

Any pics RS?

TIA

RocketSlug

Sorry, I haven't replied in so long. . .I will dust off the digital camera and get a photo on here of what it looks like.
As for 255/40/17 on the fronts. . .There is almost NO overhang, and I believe it indeed would work on the front wheels. In fact, that's what I will probably eventually do when I need new tires. I don't think I can measure the overhang, it is under 0.5 inch or less.

17x8 wheels are plenty big and there are a lot of tires that can fit without modifying odometer/speedometer. The perfect replacement tire to match stock diameter is 265/40/17, which is what I should of put back there.

Another note on my 255/40/17's, they almost never slip on a launch, but when they do, it seems like the VSC and Traction Control are more aggressive on the 2001 gs430. I lit them up last night on an offramp. . .can't wait to see the patch.

I drag with them tomorrow.

GSman

iTrader: (2)

Rocketslug,

Any pics of the 255/40-17 setup on frt and back would be appreciated.

Thanks,

RocketSlug

Ok,

Sorry for the wait, but it was too dark when I got back from the track for photos. The 255/40/17s did what I wanted them to do, I had no slips off the line, and I feel a lot better about doing burnouts on $250 tires instead of $500 ones.

Ok, to clear up confusion, I have stock 235/45/17 (stock Z rated) on front, 255/40/17 (DiscountTire H rated) on rear. Because 255/40/17 does not overhang the rim of the wheel, and because it is actually 1.7% smaller in diameter, I predict the following combination for those who have the stock gs4(30) 17x8s. When its time for new tires, try:

255/40/17 Front
265/40/17 Rear

This would result in less than 1% change in mileage and odometer, since 265/40/17 is almost the exact diameter of stock 235/45/17.

TMitchell

I may just go with the combo your talking about. My 95 540i was 235/45x17 front and 255/40x17 rear. I did some checking and found out, as you have, that 265/40x17 would have been a better match, but the tires I wanted didn't come in that size.

gs4to4

Please post some pics. Can't wait to see how that setup looks.