i have an 88 10th ann. w/ many mods, including a garrett t3/t4 hybrid turbo, street perts, and a greddy profec b-spec II boost conroller. anyone who has this type of boost controller knows all of its complex options. i have been able to get a good lo boost setting, with good spool-up time and a contant 8-9 psi. but i cant get it to set the high boost where i want it. i want it at around 15psi. it always seems to just fall off after 5000 rpm. it will go up to about 11-12 psi and just drop. i have noticed though, that if im not on full throttle the boost is much more conststant. holding at around 12.5 and droping off near red line. has anyone ran into this prob or have any tips? if you do have this set up and are running a consistant high boost, what arew your percentages and settings? truly anyt help would be wonderful; the car just isn't showing its true potential w/out it.

thank you for any help

 

What wastegate spring do you have !? It's general concencus that you can't exceed the wastegate spring by 3X it's base spring rate....
I.E. 8'lb spring, max boost 24 lbs. Otherwise I'd expect the kind of erratic behavior you're talking about... How are you plumbing the Profec into the wastegate would be nice to know, and have you checked all your vacuum lines ??

 

i have checked vacuumes. i am running 4mm hose to solinoid. i did turn the the limiter off and that solved it. but after that it didnt have the power it should at 14 psi. i richend it up and that solved that, but now its still falling off and only going to 12-13 psi and droping off at 6000 rpm. i believe i just need to mess w/ it a little more. thanks for the input. if you have anymore i'de be glad to here it