I run a 31.9" tire with 4.56's and it's great on the street. I loved it, every gear is usable, 85mph was around 1800rpm and it makes it appear the 4.8 has torque. Now that I'm able to build more boost in first gear, I find myself shifting into 2nd really early. Also if I ever go to the track, I'm going to need slicks. They don't make a 32" slick for a 16" rim that's not 2 feet wide and under $200 a tire. So that leaves me with 28" slicks. With my current tire size and gear ratio, it's equivalent to a 26" tire and 3.73's which is very common in the car crowd. F-body guys run 3.42's and higher with 26" tires and they pick up some mph and lower their ET when they switch from 4.10's or 3.73's. Turbo's love high gear, but there's a happy meduim in order to get the weight moving.

As for you building boost TURBO8, you shouldn't have a problem leaving with boost. Don't you have a 2-step? I would imagine you'd be able to leave on at least 10psi. I don't have a boost controller or a 2-step or anything, but just by messing with the timing and fuel in my tune I can build 5psi by just reving. I hit a full 10psi in neutral the other night, but it took awhile to get there.

Anywho, I planned on buying a used set of 3.42's and running a 28" slick at the track and a 28-29" tire on the street. 6th gear won't be totally un-usable at that rpm level, but then again 5th would be that much lower of an rpm. I just worry that a 3.42 and a 28" tire won't be enough to get my 5000+lbs moving. I think it's time to start the weight reduction. If only they made a 3.55 for our rear ends.

 

I dont think I should have any problems off the line as far as boost goes. I was just thinking about between shifts, but I have not tryed the 411's at the track yet. Well see. Sounds like a good plan.

 

Sounds like you are taking a look at the f-bodys on tech. A couple of guys have done just that. But they run ~26" tires.

 

Yeah I was thinking of runing a 26inch slick or drag radial for the track.

 

And then you would step back up to a ~30" tire for the street?

It does sound like a proven combo to copy, at least on the track side of things.

 

THat is the plan, now if I could just get the wife to go for it. Wish me luck!