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skimp930 skimp930 is offline
Registered User
Join Date: Dec 2011
Location: Atlanta, GA
Posts: 86
Another overboost situation


Got the car back from shop after top end rebuild. Here's what I have done so far:

3.3 Stock P/C and stock 7/1 compression
Heads port and polished and increased head size to 38mm
GT35R turbo
B&B headers/ Rarlyl8 street muffler
Full bay Garretson intercooler
Rarlyl8 adjustable WUR/ Fuel head modified for more fuel
New fuel injectors
964 cams
964 BOV
swapped to 1 bar spring to stock wastegate
New clutch/pedal assembly/clutch cable
AFR gauge installed

Started breaking in the engine and I THINK I'm hitting the overboost switch. Before the rebuild I had .8 bar spring which netted me .9 on the gauge due to better flow from my headers. Now after switching to 1 bar spring and other things (see above), I get 1.1/1.2 bar and I feel I'm tripping the overboost sensor. (fuel seems to stop flowing and I loose all power, face to the windshield experience, with a large backfire(almost gave my wife a heartattack)). Curious to know what my options are and recommended path to take.

Also, still working to solve my rich AFR mixture. Not sure if this affects overboost.

Thanks for help,
Old 06-16-2014, 08:43 AM
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