intercooler pipe size?

[Tim Barnum]

What size intercooler piping is the best for a gts 76 turbo, stage 2 heads and a powerstroke intercooler? I also have a 70mm t-body. My car has 3.5" intercooler pipe now and i think it's hurting spoolup and performance. Thanks Tim

 

[BAGN]

3in should do the trick. Thats waht PTE & Dequick uses with there intercoolers.