17 Inch wheels, what size tires would be proper?

[Spaz]

Alright guys i'm looking to buy some 17's for the car, i think the offset is et37 or et40
and they are 17 inch rims. i know very little about spacers/tire size comparison and so on. i was just wondering what size spacers i will need and also what size tires will be proper for the car? and will i need to roll my fenders?

thanks alot

[rwh11385]

how wide is the wheel?

if it is 7.5 my preferred offset is ET20 because it puts it right up against the fender (perhaps some rubbing issues, but fender rolling = badass :twisted: ) My 7.5in wide wheels, ET20 require the fenders to be rolled a little, but they look sweet filling with well! However, my rear is fooking slammed low, so you might not have that problem.

tires = 215/40-17 standard issue.

maybe 15mm spacers for ET37 and 20's for the ET40. I **think** Et25 would work as well. Not sure.

[Kavkazia]

If wheel is 17x7, you'll be alright with et 37-40mm, but it will look little tucked in.

As said before 215/40/17s are way to go.

Over here, no rubbing issues on 17x7s with et33mm offset and 215/40/17 tires.

:)

[cheades]

Depending on how lucky you are you may be able to get away with 5mm spacers or 8mm, I got 17x7.5 Kosei's in 35mm and they fit fine with no spacers and 215/40 tires. The front is the only place you need to worry about.

[Jordan]

My 17x7 ET38 MM11-2's rub the strut in front without a spacer.

This is no tire on at all, the wheel physically contacts the strut.

I run 10mm hubcentric H&R spacers all around. I would like 15-20mm in the rear.

[MattM20]

i ran 215/40 on 17x7's et20 without any problems

[Spaz]

alright thanks so far guys, but will this mess up my spedometer at all, and is there a correction?

[Jon325i]

alright thanks so far guys, but will this mess up my spedometer at all, and is there a correction?

The tire aspect ratio may be off a bit....but not too much. If its slightly undersized then your speeds will read higher than your actual speed and vice-versa with oversized tires.

I can't remember what the aspect ratio is for the stock wheel/tire set up (someone here is bound to know). Compare that figure to what you're interested in buying.

Jon

[Rob]

http://www.miata.net/garage/tirecalc.html

comes in very very handy

stock size is 195/65/14 afaik

[Jon325i]

http://www.miata.net/garage/tirecalc.html = :up:

I had forgotten about that link. It now resides under Favs. Thanks for posting.

Jon

[Sean]

Yeah, I have that book marked. THE SWEETEST tool to have when trying to find a good tire size. :D 8)

[M42Technik]

Awesome tool! But now I know that my speedometer is %1.2 fast. Oh well ES100's are sweet anyways. :twisted:

[darien28]

i may be selling my 10mm hubcentric spacers soon. they have a 72mm outer lip to fit most aftermarket wheels. (i.e. Enkeis).

I can also turn them down to whatever outer hub size you need as long as it doesn't make the walls too thin.

[Rob]

I actually prefer an optimistic speedo and undersized tires, slightly better gearing and it keeps me out of trouble, sort of.

[grlaneriejr]

Hey guys, I'm not an expert, but I can give you an easy way to figure out plus sizing.

Each inch you increase in rim size, your treadwidth and aspect ration also increases, and this will keep the tire height the same size (=/- 10%).

In other words,

185/65R14 = 195/55R15 = 225/45R16 = 235/35R17

Since that would be way too wide for our cars, have your tire dealer find something that will be the same height as a 235/35R17 and that's what you can run for tiresand keep the spedo accurate. Don't know about the rim offset factor, though.

Find a good tire dealer in your area (not an el cheapo chain, but a place that knows about tires) and they can rattle this stuff off in their head. If not, Michelin makes a book that lists EVERY tires height and width, and they can look in that.

Hope this helps