mike h wrote:
 >
 > Paul, I havent' been back on the list since February or so due to my
 > workload, but I have a question for you and your bunch of engineers that
 > no-one else has been able to approach with an answer.
 >
 > I did the math for speed of sound in in/sec and the time of the exhaust
 > pulses at 5500 RPM (0.0109...) and it works out to almost exactly 12
feet.
 > This makes sense, as that is a pretty good length for a long primary
system.
 >
 > What I'm trying to figure out is some sort of equation that will show me
 > harmonics; IE 1/16 of the 12 feet is 9", which would make an adequate
length
 > shorty header. But I don't know if my reasoning is sound.
 >
 > End goal is to have as short an individual runner header as possible
before
 > a collector and/or expansion chamber, that's better efficiency wise than
the
 > stock log manifold.
 >
 > Engine, if it matters, is a stock port 1985 12A.
 >
 > can you put this question to the list and see what it joggles free?
 >
 > Thanks!
 >
 > Mike Harrington
 > gtx1990@hotmail.com

-mike h wrote:

Exactly what I wanted - thanks a lot!
- 

 
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