The 135/185 is a MAC motor by CMB, also the new cmb s are using the same timing with good results. I run a AA parabolic pipe (or the old andy brown parabolic which is the same thing. The drum timing is 35 /62.
My 90 dub jett will do 16,000 on a cool day 15 nitro 11/8 apc prop.. I opened the carb to .475 and opened the case tracts a bit matched the ports.
I also believe the higher intake on the transfers helps low end for boats getting off the shore line with that
big speed prop. Planes it makes for a easy needle setting. As the blow down gets wider you may get the top end but low end suffers.
Rich B.
Last edited by SACKRC; 12-14-2017 at 07:12 PM.