turbosmart ic mbc install questions and boosting problems

[slidewayzka]

just installed my turbosmart in cabin manual boost controller it comes with a boost tee pretty easy install except im wondering if im supposed to use the top nipple on the mbc for anything. its a in cabin controller but i kept it in the engine compartment and all the instructions say for that upper fitting is mbc exhaust fitting route hose to engine compartment so i left it open being its in the engine bay thinking the instructions were just stating that it releases air that shouldnt be in the drivers compartment!? am i wrong or does it in fact need to be used? also i have it set on the lowest setting but when i went out for a drive it'll boost to almost 20 psi by like 3500 then lower down to like 16 or 17 psi, what would cause that?

i bought this because i have a 92 talon tsi auto with just a GEAR intake pipe, k&n filter but my boost gauge was reading 15psi (autometer) and im installing a full 3" exhaust tomorrow downpipe back and i heard that going all 3" will raisr boost alot. since it was already at 15 i didnt want to hit boost any higher but this mbc at the lowest setting is boosting 20psi? i know that the 1g auto have the smaller 13g turbo but doesnt it also have the 390cc injectors? any ideas on what the hell i need to do?

 

[winterftbl]

you have your boost controller wired wrong. If you can upload a pic of it