My friend Mean Dean Travis had both a fully tricked out FMF RM80 and a fully tricked out DG RM80. I thought they were both too pipey for their own good but it's damn hard to soup up a 80 and not make them too pipey. I agree that most people should leave their ports alone for just F'ing them up but then there are some of us that can actually port. Cleaning up ports does make a difference IMO but it really depends on what you start with. Back in the seventies, a lot of them came out of the crate looking like crap! Without changing the timing at all you could often get things flowing a lot better. The trick with the tranfers is to keep their "aim" right. I think a mirror polish on the exhaust does more than keep carbon from building up. It helps them FLOW. I use to get mine like a mirror and then every couple of tanks put the piston on TDC and clean them back up real quick for big payoffs! A friend of mine's dad use to polish the inside of his pipes with a frayed auto emergency brake cable. He said it made a noticeable difference and from my experience with exhaust ports, I don't doubt it although I have never tried it.
I know exactly what willis is saying about velocity over volume. I could look up the tried and true formula that proves this. More tuners should keep velocity in mind over volume but they don't. I grew up around short track races and I have seen SO many strokers tuned to a stand still for trumping volume over velocity. Most often by hogging out exhaust port height but . . . . High RPM power? First you have to GET to high RPM!!
supershaft screwed with this post 07-29-2012 at 09:54 PM