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RarlyL8 RarlyL8 is offline
Crotchety Old Bastard
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Join Date: Jan 2000
Location: Huntsville, AL
Posts: 13,691
I did a fair amount of header research when designing our equal length 930 headers. Conventional wisdom at the time was the shorter the better. Turned out that was only half the story. The full story was the shorter the equal length the better. What true equal length primaries and secondaries do for you in a turbo application is allow the engine to produce more torque off boost and then to produce more peak power on boost. This is in a street application mind you, racing is a whole different ballgame. I dyno tested every system I could get my hands on using the same engine. The equal length system is magic. The tuned sound alone was worth the effort. The key is for each pulse to reach the turbo in the same timing as the firing order, not a mish mash of odd fire pulses. Each pulse hits the turbine in a coordinated efficient beat.
Building short tube headers is easy and gives you a high percentage of gain over standard heat exchangers. I would not have gone to all the effort and expense to build a tuned system if it had no added benefit. This is not a new or unique idea.

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 05-09-2014, 05:07 PM
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