Thanks! I wish looks = performance. After all that, most I got
out of it was 10.2K rpm. Then I tried reducing the size of the
boost port by putting epoxy on the outside wall, and also lowering
the 'FDA' ports. Result was 9.2k max, and when I opened the
motor again, almost all the epoxy was gone. Back to drawing
board.
Then I tried increasing the main transfer channels by cutting
them all the way down as well:
That got me back to mid to high 9k's... Then I replaced the head
with one that had smaller squish band, raised compression from
118lbs to 140, retarded timing ~1degree, and lowered barrel
by using silicone gasket maker instead of base gasket.
Much better! Almost, if not all back to step 1
(10.2k rpm).
Now we've had a few fairly cold days, and I noticed noticeable
performance increase, so I should try one size smaller main jet.
It did an odd thing on a test run though. Porting should be for
around 10.5k, but when it gets to around 9.8-10.2k, it will quit
accelerating even down hill! Like the motor refuses to spin
any faster even when the load is reduced.