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mark houghton mark houghton is offline
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Join Date: Jul 2008
Location: Central Washington State
Posts: 3,893
My thoughts for what they're worth.

Ditch the 1.0 bar spring and try a .9. Overboost "spikes" are fairly common when going to a good free-flowing header system.
Second, get a decent boost gauge that tells you with confidence how high your boost is going. The overboost cutoff switch - when new - I think will activate somewhere between 1.2-1.4 bar. An old switch, on the other hand, may activate sooner. Again, you need to know exactly where your boost is at in order to decipher if it's an oversensitive switch or if indeed you're running high boost spikes.
Third, about this loud "psssssst" sound you're used to hearing. Unless you are running with an external blowoff valve modification that vents to atmosphere, you will never hear that tell-tale Ricer psssst when you shift gears and the valve opens. The stock system includes a recirculation valve that keeps the boost contained and doesn't allow it to vent to atmosphere. You should hear nothing when shifting....and should hear a nice loud roar when you've reached maximum boost and the wastegate opens to divert some un-muffled exhaust.
...and one more thing: Make sure that you have the boost signal hose connected between the IC and the WG. Your overboost could be as simple as that....the WG not opening at all.
Mark H. 1987 930, GP White, Wevo shifter, Borla exhaust, stock everything else. The result of a massive Pelicanite good will fire recovery effort. Truely an open book, ready for the slippery slopes to modification.
Old 11-10-2010, 10:44 AM
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