Tire size calculator

[MR 325]

Looking for aftermarket wheels and tires for your E30? Are you wondering what size wheel and tire will land you as close to the stock size diameter as possible? Use this handy tire size calculator to do this!

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

[Justin B]

There was this other one. I forget where it was though, it was at some online tire shop though. You could enter the original size (I think the car too? and it would know?) and like 3 others and it would show how tall they are, rollout, all sorts of things and speedometer error. Anybody know what Im talking about? :\

Nevermind, found it.

Here's another then--

http://www.1010tires.com/TireSizeCalculator.asp

[bimmer8604]

good links, thanks for posting!

Kyle

[bsut]

my favorite tire size calculator

http://ejelta.com/tiresize

Lets you explore a range of possibilities all at once

[permit]

http://www.bimmerzone.com/speed.htm

[M42Technik]

For those that don't know, the stock size on E30's is:

195/65/14 for 318i, 318iS, 325i, 325iS, 325iC...

205/55/15 for 325iX and M3...

[89is]

http://www.willtheyfit.com/

This is the one I use, I like it fairly well

[Highway1]

I was searching for that site forever. thank you!

[Ryann]

http://www.rimsntires.com/specs.jsp

[Sagaris]

I made my own in Excel which allows you to see what to expect when changing tire sizes as well. If you want to go from 195/65-14's to 195/60-14's it will give you the effective differential ratio change, which means going to 60 series will be like changing out a 3.73 diff to a 3.85 diff.

It also spits out the old vs new tire diameter and circumference in both mm and inches to save some time calculating. Then on another tab it has the typical gear ratio calculator for a 5 spd transmission (you input the gear ratios) up to 10,000 rpm. If anyone wants the file I can email it to you. Just PM me your email address

I could also add in speedometer error if anyone is interested

[mutty]

1010tires.com