DIvorced downpipe/fuel cut woes

[Skeezix]

Alright so Tuesday was great got the BIC DDP put it on went great, quaility part. Now I have this old manual boost controller had it set to about 10-11 PSI. Now I can't put it down without it hitting fuel cut, so I backs the controller out a bit, still hitting it, back it out more and it falls apart lol. So my boost controller was at its limit for low which was like 8 PSI and creeping. Routed around it and set back to stock boost, hits 6 PSI right away and creeps up from there usually to about 10 PSI by the time I shift. Hit cut once like this when I had it to the boards in fifth doing 100 MPH. Had some problems with fuel cut before but not this bad. Was running open 2.5" downpipe and stock elbow no problem. SO question is,

A. Wastegate actuator is weak
B. Boost controller is fucked
C. Exhaust flows too efficiently with and open BIC DDP
D. Other suggestions?

Any help would be appreciated. As for exhaust it's not getting a muffler,cat, resonator, etc. Straight pipe all the way, was thinking 3.5" downpipe back but that may be pointless being as the DDP is 3" so should I just get 3"? And my mods are big FMIC/hard pipes, short ram intake, and DDP

 

[tyang82]

try running with out the boost controller. if it doesnt fuel cut then put one washer on each bolt between the compressor housing and waste gate actuator.
i put 3 washers, fuel cut bad. 2 washers, fuel cut. 1 one washer, no fuel cut, but i scare myself thinking something might blow.

 

[Skeezix]

Already running without controller. Creeps from 6-11 PSI or so.

 

[peste noire]

i would say maybe boost leak??

 

[tyang82]

Mine was like that with out a boost controller. Blown head gasket, rebuilt head then back to boosting stock boost.just saying, might want to do a compression test along with tightening the ic clamps.

 

[GrimJack]

Porting out the wastegate and hole in the ddp for it might help with the creep.

Still running the stock turbo?

You might also have a leak somewhere between the turbo and the intake manifold, which would make you hit boost cut early.

 

[Skeezix]

Still running the stock turbo but it starting to get some play an burn out so I just sent my other one out to Albert for a 57 Trim upgrade. Was thinking of porting the wastgate hole on the turbo. And I will look into my intercooler pipes tomorrow. I am waiting on a coupler for the 3000 pipe to throttle body as the stock one split. Got something going there for now but it's not the best. That may be my problem but could still be a few days for the coupler.

 

[radiod]

Porting out the wastegate and hole in the ddp for it might help with the creep.

Still running the stock turbo?

You might also have a leak somewhere between the turbo and the intake manifold, which would make you hit boost cut early.

I'd check for boost leaks first, but I can tell you a good exhaust on a stock turbo will get you up to fuel cut. My car did the exact same thing you described. I had also swapped exhausts with a buddy that had a perfectly stock car so I could get through emissions and while my exhaust was on his car he had the exact same things happening.

My exhaust was a BIC DDP + cat delete + 3" version of the BIC Thunder exhaust. I later added a high flow 3" cat to the system so I didn't have to swap the entire exhaust for emissions and it wouldn't hit it as fast, but still would hit it consistently under high load ~4k rpm. I never did get as far as trying to port the wastegate, so that may be worth a shot. It was on my list of things to try but didn't get done before I sold the car.