Perry Casson wrote:
        >
        > Using the Spintech part # system as defined  by
        > http://www.spintechmufflers.com/spintech/styleimages/index.htm
        > Are you going to be making  #9137 or #9139?  From what I've read if you do
        > not use collector as in #9139 has you loose virtually all gains from
        > attempting to build a tuned exhaust.
        >
        > Perry Casson


        Perry,  I think that we need 2 inlet pipes of 1.75" each and 1 outlet of 2.25".  The reason for the 2 separate inlet pipes opening into the muffler is because the reversion wave for the scavenging of the combusion chamber starts when the exhaust pipes 'sees' an 'open' area such as an atmospheric opening or the opening to the muffler.  Each pipe should see this change independently of each other so that the scavenging can be timed for each cylinder.  Racing Beat discusses this in some detail as well as most Hot Rod books on exhaust.

        Ken Powell

 
The AirCraft Rotary Engine NewsLetter.  Powered by Linux.
ACRE NL web site. http://home.earthlink.net/~rotaryeng/            
Copyright 1998-2002 All world wide rights reserved.