Would a 305/45/18 tire fit on a 18x9.5 inch rim?
Also would a 19x11 inch rim fit period?

 

I am going to have to say no to the 305's on a 9.5 inch rim...do the math....305mm is about 12 inches, so you would have 2.5 inches not on the rim at all.....

I think that 19's would fit you would just have to get a tire size that is appropriate with a fairly small sidewall...

 

the tire will get inflated and seat to the wheel. I am gonna have to say a 305 could fit, because SUV's running 20's get 305's and they have 9-10 inch rims. And about the 19's, you would need something with a 30 aspect ratio

 

The only thing with the SUV's running that size is two things...first off, if they are 10 inch wide that is a big difference even though it is "only" 1 inch...and the biggest thing would be the sidewall difference....you can run a wider tire on a narrow rim if you increase the ratio for the sidewall....

For example I am looking into getting 255's for my 8 inch rims....for a 255/45 an 8 inch is the recommended, but for a 255/40 the recommended jumps to a 8.5 inch....just an example

I would not recommend putting a 305 on there, you are not going to get a bigger contact patch that way...just throw on a 285 or something....

 

Thank you both for your replies, Nitto makes a 305 drag radial which is why I was contemplating the idea. However I will just leave my Z06 rims for street driving. I am probably just going to run 255 slicks on stock salad shooters at the track. If I have traction issues which I probably will I will just buy some 17x11 Zr1's and throw some slicks on those...there goes my rear end!

 

The 305/45-18 is almost 29" in diameter. From my experience you can't fit anything larger than 28" on a 4th Gen without taking a canopener to the wheel openings. My 28" ET Drags needed 1.5" cut off the rubber bumper cover. 29" tires will also have the same affect as swapping your 3.42 gears to 3.04's.....

BFG now makes 18" drag radials in their g-Force tire.