So I'm wanting to change the rims on my Mustang. I have 16" factory alloy wheels now but I want to put low profile tires on it instead. Do I need to put 17" rims in place of the 16" to make sure that the wheel well stays filled, or what do I need to do? I just want to make sure that I don't leave too much space between the actual tires and the fender.

 

Have you lowered your car yet? If so then the 16" rims might look ok. Either way, lowered or not, I would go with the 17" rims so that they fill in the weel well really good!!

 

I haven't lowered it yet, but I plan on tossing in some 1.5" or 2.0" lowering springs. Would the 2.0" still be fine later on if I put 17" rims on the car?

Also, would I need to do anything to make sure the speedometer still reads correctly or are the speedometers of Mustangs not tied to the diameter of the wheels?

 

The 16" tire is getting harder to find in the sizes you will probably want. The 17" package looks like it will be around for some time. Unless you drive on a pool table all the time a two inch drop is not very street friendly.
RB

 

Yes the speedo will get screwed up if you change the overall height of the tire your stock height is 26" i believe so as long as you stay close to that height the speedo will stay close.If you go taller you will need a speedo gear or a tuner to correct the problem.

 

Not true about 16" tires. There are PLENTY of different sizes and brands available.