Best wheel sizing...

I will be getting some new 17x9.5" wheels. i can customize the backspacing.
My question is this...well actually i have 2 questions...

1. I want to have the new wheel stick out just like .5"-1" more than the stock wheel. What offset do i need to accomplish this?

2. Will 245/35/z17 tires be the right size for these wheels?

Thanks!

If the offset is correct, these 17x9.5's will stick out further, since they're 1.5" wider than what you've got now. You might get 3/4" on both sides of the wheel.

275/40 is the perfect size tire for 17x9.5's. If you wanted to stretch a 245 on those wheels, 45% would be a better aspect ratio than 35.

The stock 16x8" wheel has a 55mm offset. That means the front edge of the stock wheel sticks out about 2.3" from the face of the hub (frontspace). That means for a 9.5" wheel, you are looking to move the outside edge of the wheel out 0.5" to 1.0". To do that, you would need an offset in this range:

2.3" + 0.5" = 2.8" frontspace = 60mm offset (too large a backspace, may not fit without rubbing on the steering knuckle)

2.3" + 1.0" = 3.3" frontspace = 48mm offset. This is OK, and will look exactly like the 17x9.5" OZ Monte Carlo's in this picture:

http://cjcfo.fbody.com/members/injuneerzz@aol.com/PhotosD/3_4View.jpg

You could even go a little lower on the offset... the TT II 17x9.5" wheels are 45mm offset, I believe, and this car has the TT II 17x9.5's in the front:

http://www.kellydrown.com/Showcase/120-2036_crw_std.jpg

On the tires, you really have to match the stock tire diameter. A 245/35-17 would be about a 23.8" diameter, which is almost 2" smaller than the stock 4th Gen tires (assuming your car came with 245/50-16's) and would drop the car 1" closer to the road, and would open up the already huge gap between the tire and the fender by a full 1". It would look terrible.

As noted above, most people will use a 275/40-17 or a 285/40-17 with a 9.5" wide wheel. But if you want the skinnier 245's, you need the 245/45-17, as noted in the post above.

I'm going to be dropping the car an inch too so....

I want my wheels to look like the wheels in the first pic link you posted.

Thanks!