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911nut 911nut is offline
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Join Date: May 2001
Location: Michigan
Posts: 2,511
Thinking more about this.....I decided after installing the hybrid bov that I needed a way to vent air when the boost does not achieve maximum (13.1 psi on my car). There are times when it only reaches 10 psi and then there's off boost events too.
Also my desire was to keep the turbo freewheeling during these sub-maximum boost events. This meant that the decel valve could not be discarded, so I disconnect the decel valve output and capped off the hose leading to the intake. Now the decel valve operates normally (in that it opens when receiving it's vacuum signal) and vents to atmosphere as opposed to shoving air into the engine behind the throttle butterfly. This allows the revs drop quickly, which makes for much faster shift, smooth clutch operation and increased clutch life. A side benefit is that there's no need to plug the intercooler openings for the recirc valve and the decel valve.
Paul B.
'91 964 Turbo
Port matched, SC cams, K27/K29 turbo, Roush Performance custom headers w/Tial MV-S dual wastegates, Rarlyl8 muffler, LWFW, GT2 clutch & PP, BL wur, factory RS shifter, RS mounts, FVD timing mod, Big Reds, - 210 lb
Old 10-20-2008, 03:09 PM
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