currently i have 3 wastegates on my 98 and still is not enough to keep boost psi to a safe limit, the internal gate on the s300, a 35mm external gate from manifold to hot pipe, and 38mm ext gate from manifold and dumped, i have a head being built with o-rings at j&h jerformance, i want to get this head on, install an ats manifold, studs, and bump up to 140hp sticks (5x0.014), but the question is, will a bigger gate from the manifold to the hotpipe help me at all? right now i am seeing 25-30psi from the s400 @50psi over all, with out the third gate, with the third gate i can still hit over 50 psi real easy, but it also drops 10-20psi in the cold pipe, with all the new stuff i would still like to keep it around 65 psi and i want to ditch the third gate

 

Sounds like you need to visit CompD... Competitiondiesel.com that is, there`s a LOT of knowledge over there and a ton of threads on gating twins. I personally have ZERO experience with twins, but I figured I could steer you in the right direction