upgrade wheel package for my 05 gt
 

The choice between 18" and 20" rims on an 05+ is up to you. If you like the big rim look and have the money to pay for the tires go for it. I personally like smaller 18" rims, due to tires being cheaper and easier to find and better performance. Everything else sound like it was copy pasted from the American Muscle website so your sizes are fine. I'd go with a 275mm tire for a 9" rim and a 295-305mm tire for a 10" rim.

Honestly id say 18x9 or x10 either way not 20s. 20s are just bigger, not better in any way, after 18" your just loosing performance and a smoother ride. Plus i think 18s fit very well to all mustangs 20 looksa bit big to me.

ok great I'm starting to lean more to the 18" but now the question is what would be the best performance tire out there that would give me the best bang for my canadian crappy buck? Anybody that has tires that they would recommend?

Nitto's are a pretty good tire for a good price. :D

By the way, welcome to the boards and thank you for not being a turd. :)

Only go with 20's if your local roads are absolutely flawless/pothole free. Otherwise there is a pretty good chance that you will bend one of them. Guy on one of my other forums refused to listen to us when he was choosing wheels, and he ended up going with a set of 20's. He was so pissed at our "hatin" that he left our forum and went to another one. And sure enough, someone saw him on his new forum complaining about bent wheels within a few weeks. One pothole had taken out both wheels on one side of the car. Perhaps if he had listened to the advice of people that had gone through that before, then he wouldn't have had a problem. In my opinion, 18's are the best mix of performance/durability available. They look great, and they still (in most cases) have enough sidewall to adequately protect the wheels.

thx for being easy on the rookie- are you driving on nitto's now?

Yep. Been driving on Nittos for 7 months. I have the 18x9 wheels with 255/45/18 in front and 18x10 wheels with 285/40/18 in back.

I'm assuming you like them or too early to tell? We seem to have similar taste- going for the same sizes but chrome rims, also 05 blk with red leather,satin alum dash etc.