Well this is what happened I just bought some 16 " rims for 300$ but the two in the front are running 40's (tire size) and the rear ones are running 45's so when im driving at around 55-60 my steering wheel starts shaking

 

Well the different tire size probably isnt helping, but I doubt thats the cause. The difference between the 40 and 45 is just overall tire diameter. (Actually, the sidewall aspect ratio,b ut to keep it simple, lets just say it accounts for a diameter difference)

Sounds like a tire balancing issue, if it just happens at a certain speed.

 

I would make sure all the hardware for the wheel is installed properly (eg. lugs, centering rings, etc.). If installed incorrectly, these items can cause a vibration. You can also download a vibration flow chart off of our website to help diagnose the problem. Here is the link:

Vibration Flow Chart

 

well one of the rims was hit prety bad and it has a dent, it looks like they hit a bumb prety hard I also went to a tire place and theey told me taht is also because the tires a different speed something, one says83 v and the other says 77 t.

 

If the wheel has a bend in it, I would say pretty confidently that is the reason you are getting the vibration. Also, mixing a "V" speed rated tire with a "T" rated tire is a very bad idea. That tells me you have some type of performance tire (probably driectional tread design) mixed with a passenger or touring tire (probably symetrical tread design). This is a poor combination in dry weather as well as wet weather. The tires are going to handle and tread debris differntly, causing the car to have a "split personality". I would highly suggest a matched set of tires for the best and safest performance.