As far as looks go, does a 315/75-16 look similar to a 305/70-16? Does the width & height ratio of both look similar? Both would be on a 16x10 wheel.

Then how do they compare to a 305/70-17 on a 17x10 or 17x9 wheel.

From what I've been reading, there seems to be a lot of performance decreases with a 315/70-17, so I'm trying to staying from that tire and wheel combo.

Oh yea, I'll have a 3" body lift.

I know I've asked a lot of questions lately about these wheel combo's, it's just that I'm trying to get it right the first time before spending all the money. I promise to post pics once all said and done.

Greeny

 

I thought this link might help with your choices: http://www.miata.net/garage/tirecalc.html
It will tell you the differance between tire sizes and how much differance there really is. Hope it helps!

 

with 315's you'll deff feel a difference without regearing, not as much with 305's as you are talking about 2" difference roughly depending on the make of tire.

 

Try this site. You can play with all sorts of different tire size and gear ratio combos...

Tire size calculator