I'm running a Greddy b spec II and boost is inconsistent. For example: After the engine is warm I'll go WOT and hit ~13 psi (or whatever I had it set for) but after a few hard pulls I'll only get 11.5-12. I could also be set at 12 and get 10 after a few hard pulls. I have to crank the duty way up with a couple of points on the gain to get it to hold 13. The next day I'll warm up, hit WOT, and run into FC at 13.6-13.8 psi and have to drop the duty and gain back down. Is this a boost controller issue or might it be a wastegate/WG port problem? I also have the actuator mildly shimmed to hold boost longer. Stock ct26, walbro @12V constant, clean fuel system (filter/injectors), stock afm w/screw backed out, harpipes w/out leaks, 1g dsm bpv (uncrushed). Any thoughts appreciated.
