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Ken911 Ken911 is offline
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Join Date: May 2005
Location: Loxahatchee, florida
Posts: 2,711
OK i know I'm going to get a lot of negative feedback here. But here goes. For a forced induction engine equal length headers are useless. The fact that there is a turbocharger in the line causes back pressure which negates any scavenging effect of having the pulses of each exhaust valve opening and closing being lined up. The best bet for a forced induction set of headers is the smallest volume ie shorties length possible to reduce turbo lag. Now there is an exception for the twin scroll versions since the sides have to be balanced to take advantage of it. I have talked to a few people who have actually tested this on a dyno and they confirmed what i was thinking. Equal length headers are designed for normally aspirated motors so that the exhaust pulses line up behind one another ans they flow into the collector. This results in a vacuum scavenging effect in the primaries and increased flow through the exhaust valves. Any way chose to believe it or not but if there really was anything to gain by equal length headers on a turbo motor all of the factory race teams would have used them. Instead they went with shorties on the 935's and also later turbo 3.6's etc.
88 turbo Guards red Targa slant nose, and yes I am a horsepower junkie, 3.4liter,7.5 to 1 JE pistons, Adjustable WUR, Imagine fuel head, 1 bar waste gate headers,allthe cis toys. Now apart to become the next EFI monster. fabbing my own intake, headers Individual throttle bodies, MS-3, pauter rods, Xtreme twin plugged heads, gt-2 evo cams cop's.
05 Cayenne S lapis blue
Old 05-09-2014, 02:14 PM
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