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RarlyL8 RarlyL8 is offline
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Join Date: Jan 2000
Location: Huntsville, AL
Posts: 13,563
Rudy - it will help if you dump the exhause before full boost, during the spool up.

I have been developing a 930 active exhaust for over a year and have found it to be much more challenging than you would think it should be. An exhaust dump is not too difficult but the timing of the event to maximize performance advantages is a bit tricky. You have to consider A/F ratios and backpressure/spooling events as well as the same when the gate slams shut as you get off the gas.

If you use a fairly free flowing muffler to begin with these troubles are relieved somewhat.

What I am doing is going from a very quiet muffler to a straight pipe that opens at boost onset. This sudden dynamic change has to be balanced to retain smooth operation.
RarlyL8 Motorsports / M&K Exhaust - 911/930 Exhaust Systems, Turbos, TiAL, CIS Mods/Rebuilds
'78 911SC Widebody, 930 engine, 915 Tranny, K27, SC Cams, RL8 Headers & GT3 Muffler. 350whp @ 0.75bar
Brian B. (256)536-9977 Service@MKExhaust Brian@RarlyL8
Old 06-29-2008, 07:24 PM
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