I just ordered some 18x8 245 50 18 rims.. But they only fit in the rear!! I heard some one say that if i put on some 235 size tires they would fit is this true?!?!?! Oh yeh, its a 86' 735i e23.
http://img61.imageshack.us/my.php?image=jan01414fc.jpg

the tire hits the strute before they even can be mounted. its 24mm offset...

You are not planning on changing out the two wheels and tires that are show in the picture are you??? The outside diameters of the tires are wildly different!

I'd be really surprised if you could fit 245/50-18's on an E32.

should i just put smaller tires on the front the make them fit? like some 225/40R-18 or something

The overall diameter of the should be the same between front and rear. If you have ABS it MUST be the same.

The basic idea is that you want the diameter too be as close as possible to the original tires, but to increase the width. Here is some basic info. There is lots more information on the Internet if you look for it. http://www.discounttire.com/dtcs/infoPlusSizing.dos

If its not the same with the abs system what would happen? I understand the plus sizing deal. Um this guy here has the same car I have. He says he has 225 40 18 fronts and 245 45 18 rear. http://img220.imageshack.us/img220/5935/dscn25155xk.jpg (http://img220.imageshack.us/img220/5935/dscn25155xk.jpg)
I wonder did he use wheel spacers too or somthing..

Here is the same rims i have on a e32..http://img101.imageshack.us/img101/1584/93740i6bn.jpg
I think its a e32 lol

If its not the same with the abs system what would happen? I understand the plus sizing deal. Um this guy here has the same car I have. He says he has 225 40 18 fronts and 245 45 18 rear. http://img220.imageshack.us/img220/5935/dscn25155xk.jpg (http://img220.imageshack.us/img220/5935/dscn25155xk.jpg)
I wonder did he use wheel spacers too or somthing..

You have an E23, correct? If so, you will be pretty limited, width-wise, in front (probably in the rear, too). Also, 245/50-18 is a somewhat unusual tire size...

I would put 225s on the front and go with 245s on the rear, assuming they fit?

Also, if the guy you reference above truly has the sizes he mentions, he's screwed up, circumference-wise, as I would think he would go 245/40R and 225/45F. Note that I didn't run these through any Excel program to see if they come close, but they look OK at first glance...

so u think the 225's should fit the front? I already have the 245's in the rear. Should I go with 225/40 or 225/50 since the tire hits the cup that holds the front shock and that i have 245/50 in rear.

Use a tire calculator like the one here http://www.miata.net/garage/tirecalc.html.

Try to get the new combination as close as possible to the original diameter. Then check the width to make sure that it will fit without hitting anything. Make sure to consider the wheel as it turns and when the suspension settles.


Use any wheels and tires that you have and work backwards. The tire cross section (width) is the larger number in milimeters. A tire that is a 255 is 255 mm wide (roughly). A 245 is going to be 10 mm narrower, or 5 mm per side if the wheel offset remains the same.

The one in this picture looks pretty tight on the clearance on the front tires. As you turn the wheel I'd expect that the outside edge to come pretty close, or contact the inner fender cover. The car in the picture is an E32. You have an E23, right? Big difference.

You are trying to put on tires and wheels from a 7 Series that is four generations later and four inches larger in diameter??? Good luck! The original size on the E23 was 205/70-14.

Use a tire calculator like the one here http://www.miata.net/garage/tirecalc.html.

Try to get the new combination as close as possible to the original diameter. Then check the width to make sure that it will fit without hitting anything. Make sure to consider the wheel as it turns and when the suspension settles.


Use any wheels and tires that you have and work backwards. The tire cross section (width) is the larger number in milimeters. A tire that is a 255 is 255 mm wide (roughly). A 245 is going to be 10 mm narrower, or 5 mm per side if the wheel offset remains the same.

The one in this picture looks pretty tight on the clearance on the front tires. As you turn the wheel I'd expect that the outside edge to come pretty close, or contact the inner fender cover. The car in the picture is an E32. You have an E23, right? Big difference.

You are trying to put on tires and wheels from a 7 Series that is four generations later and four inches larger in diameter??? Good luck! The original size on the E23 was 205/70-14.

When I used that calculator it seems like 225/40-18 would be a good size, that close to the original tire size. So when I get some 225/40-18 Fronts and some spacers the rims should fit right??

You will have to check the clearances to see if it will rub. Use a known tire size and measure for the additional width as explained earlier.

i have 225/50/16 on front and rear, u can probably fit 235 in front and 245 in the rear