Took my friend for a drive yesterday, 1-3rd gear. Running autochrome junk manifold and wastegate. Boost gauge showed 13 psi by end of 3rd even though wastegate spring is 5 psi.

Im not really worried about this if it turns out to be the manifold or the wastegate since im replacing both of those within the next week or two but i wanted to ask beforehand what is causing this. From my understanding on a 5psi spring its not uncommon to spike up to 8-9 psi but not 13psi.
Oh another issue might be the bov from same company, which im replacing next week as well. Its huge, friends are telling me its the right size for a twin turbo supra but not a mildly boosted prelude. Its extremely laggy. When i let off the gas i can hear compressor surge for a sec then the bov goes off. While i dont think this would cause boost creep i thought i'd just mention it.

Got one more question about the wastegate, or wastegates in general for that matter. I'm not running a dumptube right now so the wg just dumps into engine bay. Even when the car is idling i can hear the spring/valve opening and i can feel air coming out. Does the wastegate always open a bit before its specified spring setting? I always thought that the wastegate wont open at all until a certain psi is reached. Correct me if i'm wrong guys, i'm just a noob

 

Ouch.. def. sounds like a bad WG.

You need to adjust your BOV for 5 psi.

 

alright turns out i forgot to use that metal ring that goes between the flange and the WG. It was causing a constant exhaust leak as you can imagine. Car is quiet as stock now.

However the boost gauge still shows 13 psi if i hit it in 3rd gear. I am picking up a real Tial tonight, should this fix my boost creep problems???

 

I use a tial on my ssac and I don't have any creep (well maybe a pound or two).But if your going to replace it anyway then I wouldn't even bother bolting it on.Just stay out of it for a week.

 

yup the tial got rid of my problem. 7psi spring, spikes to 8