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View Full Version : Twin Engined Wildthing !!


crustycampbell
Jul 19, 2007, 06:38 AM
Just thought I would throw this out there for the purpose of
discussion....
I am in the process of building a Wildthing hull from the plans on this
site. I will power it with twin in line 25cc weedwackers. The question
is do I use seperate tune pipes and run the engines 180 deg. out of
phase or run them in phase with a exhaust manifold feeding both motors
into a custom built 50cc tune pipe ??


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crustycampbell
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Thin water
Jul 19, 2007, 11:58 PM
You will probably have to run them in phase if you are going to try and
use one pipe. It might not work as the shock wave inside a tuned pipe
draws the next charge into the engine. If you ran them out of phase one
shock wave would probably disrupt the other engines running.

I only have played with motorcycles and they always have one pipe per
cylinder in 2 stroke engines (as far as I know, but there may be
something that is different).

JIM


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Thin water
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crustycampbell
Jul 20, 2007, 05:01 AM
Thats it jim I dont know how the return wave would be affected being
split in two going back to the engines. Hell of a job making identical
length manifolds to fit in the space I have to. I will have to get my
tune pipe calculator out and see if it is even physically possable to
fit a 50cc tune pipe on the boat !


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crustycampbell
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