Confused by rim sizes - BMW Forum

lsmith42 · 09-14-2006, 06:04 PM

Couldn't think of a better title...

My girlfriend's 1998 1/2 (?) Z3 (2.5, I think) needs new tires. It has BMW 15" rims and 205/60R15 tires. The issue is that every web site I go to (and a few local shops) insist that the car came with minimum 16" rims, and some shops will not even sell her tires because they are not the original size.

She is not the original owner, so the rims may have been swapped before she got the car.

Are these the wrong rims for her car? Any ancient wisdom would be appreciated.

///M Power · 09-14-2006, 06:27 PM

Any pictures? I thought they did come with 15" wheels standard.

lsmith42 · 09-14-2006, 06:49 PM

Quote:

Originally Posted by ///M Power

Any pictures? I thought they did come with 15" wheels standard.

Thanks for the response. Will post a picture when she returns from LA next week. I'll also get the VIN so I can figure out what this car really is...

nukeduster · 09-14-2006, 07:58 PM

Even my base model 1.9L z3 came with 16's stock, so double check they were originally for her vehicle.. you CAN fit 15's but they would be from a different bmw (that size is stock for a e34 525i, for example).

Otherwise, the size you'd need would be 225/55/15. That would be the most accurate replacement for a z3 if you actually ran a 15" wheel.

Check the offset on the wheel.. remove the wheel and there should be the word "ET" and a number after it... if its low.. (0-25) its an old 5/7 series wheel.. if its higher (35-45) its a 3 series or z specific wheel from maybe a 318 perhaps.

lsmith42 · 09-14-2006, 08:25 PM

Quote:

Originally Posted by nukeduster

Even my base model 1.9L z3 came with 16's stock, so double check they were originally for her vehicle.. you CAN fit 15's but they would be from a different bmw (that size is stock for a e34 525i, for example).

Otherwise, the size you'd need would be 225/55/15. That would be the most accurate replacement for a z3 if you actually ran a 15" wheel.

Check the offset on the wheel.. remove the wheel and there should be the word "ET" and a number after it... if its low.. (0-25) its an old 5/7 series wheel.. if its higher (35-45) its a 3 series or z specific wheel from maybe a 318 perhaps.

Thanks, this is useful!

RexKing86 · 09-15-2006, 01:22 PM

um... shops shouldnt ever bitch about smaller wheels... only larger... just order whatever is on the tire from tire rack and just bring it to a shop...

drz · 09-15-2006, 02:34 PM

I agree with Kingo. If she has 205/60/15 tires on the wheels, then she should be able to buy that same size as replacements.

Maybe those are not the wheels that came on it stock, but that does not make it unsafe (if they fit right).

nukeduster · 09-15-2006, 03:37 PM

It can make it unsafe.. larger or smaller if not oem we are always warned against using as they are a liability.. esp with alot of the new DOT laws that came out that dealers have to enforce as of earlier this year..

to some its just not worth dealing with aftermarket.

drz · 09-15-2006, 03:45 PM

Hence the "if they fit right" parenthetical.

lsmith42 · 09-25-2006, 01:15 PM

OK... got my grubbies on the car and did a little investigation. The door jam sticker says specifies no less than eight "proper" tire sizes for the car. The size that's on there is one of the three "M+S" sizes, and the only one to use a 15" rim. I can post pics tonight if anyone's interested.

It's also odd that none of the online databases get that this car could have a 2.8l. They all list either 2.5 or 3.0l.

Did BMW make a few Frankensteins just for fun? I think the black with red leather interior is somewhat rare as well.

Bottom line... she's getting some new BFG GForce Sports and an alignment today... new bushings all around when I have the time!

lsmith42 · 10-05-2006, 12:16 AM

Here are the pics (pre-new tires)... notice the array of sizes...