will 18 inch bbs rims fit on a 1983 porsche 944?

Answer 1

18" is larger than the supposedly largest wheel you can fit... though realistically, there is no reason (with correctly sized tires and correct offsets on the rims) why you couldn't fit 18" wheels.

However, there may be problems finding the right size tires to make this work, you will almost certainly need to roll the fenders in the front (and maybe the back) to prevent rubbing, and you will probably KILL the performance of the car.

A 1983 944 does not have alot of power, it's main strength is being well balanced and that it handles well. 18" wheels will increase the grip by giving a larger contact area... but you'll get a much harsher ride. The real problem though will be loss of usable power... Since you probably have 15" or 16" wheels on the car now (as it came from the factory), you'll realize about 12-15 pounds of extra weight at each corner of the car... 12-15 pounds of unsprung rotating mass!
This will be about the same as losing 16hp (more than 10% of your car's total power). Likewise, you'll be losing a similar amount in braking, and losing alot of the handling you gained from the larger contact patch.

Answer 2

They may fit. Width is more important than diameter. An 18x8 wheel will fit all 4 corners, with a 225 up front and a 245 in the rear. A 245 may fit up front with rolled fenders and a 275 may fir in the rear. I run 17s with 225 up front and 275 in the rear on my '88 and I'd run 18s if I could afford it.
The other important factor on the early cars is the offset. Check the following link, about 1/2 way down for the specs:
http://www.connact.com/~kgross/FAQ/944faq13.html
You'll see that the early cars have a 23mm offset and the later ones have a 52mm offset. That could be a deal-breaker for the wheels. Best to check the offset of the wheels first.
Here's another of my favorite links re tire sizes and overall diameter:
http://www.miata.net/garage/tirecalc.html
Also - get a lightweight wheel. The upsprung weight mentioned above is a significant issue
Good Luck!

Answer 3

18 Inch Bbs Rims

Answer 4

Annie, the number 16, 17 etc on a tire and rim refer to how tall the opening is the tire is. the rim size of 17 corresponds to the tire size of 17. a 16 would be 1 inch shorter opening on a tire than the 17 inch rim height. Annie, sorry but the 16 inch tire to 15 inch rim is actually impossible. The air would not seal against the bead of the tire to rim area. If it could by some strange fluke it would be as dangerous to the driver as removing all the lugnuts but one and having it hand tight!