Thanks for the compliment on my car. To asnwer your question on plans to lower the car, the answer is NO as I have problems with the front bumper scraping in some driveways, and if I lowered the car I'm afraid I'd have more problems.

 

18 you want some meat on those tires

 

20s on a mustang makes no sense to me. imo, it seems people who go with 20s on a mustang have an import car background. of course, some 20s look good on the mustang, but it is way too much unsprung weight and rotational mass for a performance car. just my 2 cents.

18s is the most i would ever go. 17s would be my choice.

 

I agree, I dont like the look of anything bigger then 18's and its the highest I personally would go.

 

20+ for show. 17-18 for performance seems to be the general consensus basically.

 

!7's baby!!! Well that is all I could afford when I bought them so I'm stuck for now but the tire size made a difference in the handeling. I went with 245 45 R17 instead of the stock P's.
So in answering your question I'd say go 18!

 

I like both depending on the rim, although I'm not terribly concerned with drag racing anyone, so wheel performance isn't an issue. 555's car looks awesome with 20s.