This is >>>>IMHO<<<<<<<

I am running an SDJ header (collects at the end expanding to a 3" round) and have 3" pipe running all the way to the rear. There are two 45s that put it in the proper position and I have a dynomax barrel style muffler. On the dyno...she is very hot!

NOW...last race, we were running 3" OVALIZED tubing which my engine builder and a few other collegues warned against...and...they were correct. The pipe blew out about 90"s back just past the first 45 degree section and when I say blew out...I mean BLEW OUT. I felt it happend AND I noticed a rather "noticable" drop in HP as well. (BTW...I am usually at 100db MAX)

Atilla Lucaks (39IT-7) on the other hand is running straight that turn 45 degrees and exit at the front of the right wheel. He is PLENTY good on power.

Now..what I have been told is the the "sound" wave traveling through the tail pipe is a Sin-wave. And the "trick" is to have the wave exit at the zenith of the sin. Only effective way to do this is on a dyno.

SO..IMHO...there are two answers...both relating to the sin wave upon exit.

A lot of people will experiment on the dyno with different "extentions" to see the variation in lenghts to HP. From what I have heard, Density Altitude (temp/PA) has no effect on this lenght so, once you find it, you find it.

Again, just my humble opinion....



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Balz
#67 IT-7
www.balz.myip.org
"I live my life one Apex (seal) at a time"