I searched and found nothing. I'm going to be putting on some new rubber on some 17x8's with a 35mm offset, will a 255/40 17 cause rubbing problems in the front? I will be going with 275/40's in the rear, on w 17x9.5 (40 mm offset). I'm pretty confident about the rears, but not so sure on the fronts. I currently have a stock suspension, but will eventually get either the m2 springs or the H&R's, with Koni sports. Saying that, I need to keep those factors in mind. I apologise for this redundant question. Info is greatly appreciated. Thanks.

 

That front offset is WAY too low. You will probably rub even running 225/45 17 tires. To picture things better, that width and offset has less frontspacing than a 10-inch wide wheel at the stock +50 offset.

I would suggest getting a better fitting set of wheels. If you aren't willing to do that, prepare to roll your fenders and don't go wider than 225/45 tires.

Your rears are fine, although 265/40 would probably be a better choice.

 

Why do you think that I would be better off with the 265's? Just curious. I checked the tirerack website, and they recommended a 235/45 on the 17x8's. Do you base your statements on personal experience? Thanks for taking the time to help out.

 

265/40 17s are closer to the stock wheel+tire diameter. 275/40s are much taller than stock. This will effectively raise your final drive ratio (car will have higher top speed but slower acceleration), which will also put your speedo off a few miles an hour.

235/45 is also taller than stock and tire rack only recommends it because 225/45 doesn't maintain the same load rating capability of the stock 225/50.

Your fronts are going to be close to rubbing, even with 225 width tires. The 235/45s will push it even further. You really should consider a different set of wheels. BTW, if you lower the car, it will make the problem worse.

 

Unfortunately I will be stuck with the rims for now. Do you think there would be problems if I simply go with 225/40's up front? I'm wondering if that would make my car lower in the front than rear??? BTW, the stock rims are 50 mm offset??!!!

 

Of course 225/40 17s will make your car lower in the front, especially since 265/40 and 275/40 17s will make the rear higher than stock.

Yes, the stock wheels are +50 mm offset.

You can usually pick up a set of stock wheels for about $4-500. If you sell your current ones, you're not out that much money.

BTW, two most common 17" wheel upgrades are:

*17x8.5 front/17x9.5 rear, +40 to +50 offset, tire sizes would be 245/40 front, 265/40 rear

*17x9 all around with +45 to +50 offset, tire sizes would be 245/40 or 255/40

 

A 17X8 +35 actually has essentially the same front spacing as a 17X8.5 +40 (actually +41) - all else being equal. It'll fit ok. As rynberg points out though, tire size is the last mile when it comes to fit.

A 235/40/17 is probably a better compromise then the 225/40/17s (are there even any tire's available is this size?)

While the 275/40/17s will fit with 17X9.5 +40, I would do the 265/40/17s as rynberg suggests, to keep the overall diameters as close as possible.

 

Doh, I think I made a math error....actually, you should be safe running a 225/45 17 on that wheel. Many people are running the Volk fitment of 17x8.5 +40 with 245/40 17 tires, so you should be fine. Sorry about the confusion!

Note to self: don't answer wheel offset questions while at work....

Thanks for clearing that up dclin.

 

You guys have been great. It's nice to see that there are people out there that offer information, rather than the usual smart *** replies. So far it sounds like I should get the 265/40's and the 235/40's . I saw that rx7even has the same rims I do, and his rims are wearing exactly what you two are recommending. Thanks for all your help guys. Of course I'll post some pics once I get them on

 

Crap!! I went to tirerack .com to check out the pricing on the tires I will be getting, which are the Kuhmo exsta mx. They have a 235/45, and a 245/40. So you guys think that I will be able to get away with the 245/40's up front, coorect??????? Unfortunately the mx's do not come in 265/40's but they do come in 275/40's. Crap!!!I kinda want that low sidewall look....

 

Wait a minute, now I'm getting confused. I thought that the first #, such as 265/x or 275/x refers to the width of the tire in millimeter. If that is correct then why would the 275's be TALLER than the 265's? 275's should only be wider no? It's the sectional number that determines the height correct??

 

The sidewall height = width*aspect ratio = 275*40

The "40" part of the tire designation is the aspect ratio between the width and heighth of the tire. It is not a fixed value of 40mm.

Read about tire markings here:

http://www.tirerack.com/tires/tiretech/general/size.htm

 

Yes I believe I understand that. The # 40 simply means that the sidewall height is 40 % of the the sectional width. (am I correct?) That being the case, the sectional width has nothing to do with the overall height of the tire. I can see how a 274/40 17 would be taller than the stock 225/40 16 being that a 17 inch rims is are one inch larger. I do not know how much difference in height when comparing the aspect ratio of 40% on a 17 to the aspect ratio of 50% in a 16 . Anyone else want to comment? Am I missing something obvious?? If my info is correct , given the same aspect ratio of 40% , a 275 is not taller than a 265, just wider.

 

Yes, you are missing something obvious.

nominal sidewall height of 265/40 = 265*.4 = 106mm
nominal sidewall height of 275/40 = 275*.4 = 110mm

Note that those numbers are for "each" sidewall, so a 275/40 17 tire is actually 8mm taller than a 265/40 17 tire. 8mm = ~1/3 inch. This may not seem like much, but a 265/40 17 tire is already taller than stock, so a 275/40 is just pushing it further off.

Also, a 17-inch tire is not necessarily taller than a 16-inch tire -- in fact that's the whole idea in plus-sizing. When you go with a 17-inch wheel, you want to select a tire with a lower profile (aspect ratio) to maintain the same wheel+tire diameter. A 225/50 16 tire mounted on a 16-inch rim has the same diameter as a 255/40 17 tire mounted on a 17-inch rim.

Please read through the tire tech info section on the tire rack website. It will all become clear.

 

 

Dumb baseline question:
what is the width of the stock OEM 16 inch wheels, just to tell where this discussion is departing from...

 

OEM FD wheels are 16x8.