Half throttle boost creep issue.

[travypoo]

While driving in any gear if I accelerate half throttle as soon as I get to 4 and 5 thousand rpm my boost starts to creep up, it almost sounds like my WG is quickly opening and closing and the boost is slowly climbing. Since I am half throttle im not overboosting, the boost is just spiking up. it will be at 9, then 11, then 13, then 15. But if I have the pedal to the floor it holds solid at 17 psi and will never go over. Here is a list of mods I have done that would possibly be an issue. Thanks for the help!

-Turbosmart 38mm external gate with screamer pipe
-AEM tru boost EBC (there are 2 different diagrams, one for internal gate, and one for external, if my vac lines are set up for external i have massive boost creep at WOT, so the controller is set up for internal)
-Megan bottom mount manifold(gate flange is welded directly above t2 flange)
-GT2871 .64 (when i first put the turbo on the car it had huge boost creep, so i went with an external gate)
-Vac nipple right above the turbo for the EBC solenoid

http://img.photobucket.com/albums/v421/travypoo/Picture004-10.jpg

[steve shadows]

I suggest you invest in a Blitz Dual Boost Controller, the dual solenoid eliminated my boost surge and creep with my GT3076R 38mm wg setup immediately after setting it up with the right amount of GAIN setting.

It truly is the best boost controller for the SR, at least for the characterization of the common surge issues all SR's seem to have.

Aside from that you could invest in a Larger WG itself, i.e. 44 mm

Another thing that can cause this is if the "Screamer pipe" or dump pipe has a TIGHT BEND in it right after the opening of the dump port of the wg.

It needs to be straight as possible, i.e. like a 30 degree elbow, instead of a 45 or even 90 degree sharp bend off the WG opening.

I actually used a Muffler Flex Pipe repair pipe, which you can buy at an auto-parts store and welded that onto a 38mm WG flange and bolted that onto my WG for a very long period, this helped elminate the creep and surge because the WG gases were getting expelled more efficiently that hitting a 90 degree bend on the way out- just another thought