Going to make my own kit I decided. Just curious what size piping I need to run and what size WG and Bov. I decided that I am going to get a WG that release back into the exhaust. My setup is a 385ci LT1. Looking to run 20-24psi to make 1000rwhp. Its a GT47-88 turbo. If I cruise around town maybe on the weekends it will be set about 12psi. Is 2.5" piping to small? I was thinking that I should run a 3" dp or maybe 3.5"

 

whats the output diameter of the turbo? Try and use that size the whole system, or bigger

 

The output on a gt47-88 is like 4inchs.. you sure about that?

 

WEll, thats to prevent any loss... lol...

Got a friend with a '87 GN with a stage 2 motor. Got a T78 turbo with 4 1/2" output, and he has a 4 1/2" downpipe, and intake pipe. With a custom made Hogan sheetmetal intake.

If it was me, i'd put the biggest of everything i can fit under the hood

 

Outlet is 5" on the gt47-88... I wouldnt go less than 3.5" DP.

Saw this and thought of you: http://cgi.ebay.com/ebaymotors/ws/eB...0868&rd=1&rd=1

 

Get two. You'll have more fun that way.

Definately run the biggest down pipe you can get to fit in there.

Piping for the gate probably shouldn't be smaller than 1 3/4".

 

I think what I am going to do is run a 5inch dp reduced down into a 4inch right off the turbo all the way back to the rear axle. I am going to use 1 3/4" Piping for the Waste Gate or would it hurt anything to use 2"? The piping from the headers feeding the exhaust housing is going to be 2.5" with a flex pipe on one. What size piping should I run coming off the turbo going to the IC and coming out of the IC to the TB?