" From: Tom Jennings <tomj@xxxxxxx> " " [] " " Question: is there any likely scavenging benefit possible from running " something like 48" of skinny pipe (like 1.75") down from the manifold, " then dump into larger 2" - 2.25") from muffler to tailpipe? Keep in mind " this is a small engine that spends most of it's time 2000 - 2800 rpm " (hence the 48" number). i've read that if you double the pipe diameter at the step, it's effectively much like running a straight pipe that long. you'd have to go about to 3" for the rest of the system though. ________________________________________________________________________ Andrew Hay the genius nature internet rambler is to see what all have seen adh@xxxxxxxxxxxxxxxxx and think what none thought _______________________________________________ Amc-list mailing list Amc-list@xxxxxxxxxxxx http://splatter.wps.com/cgi-bin/mailman/listinfo/amc-list