Originally Posted by DrCharles
AndyF has a (frequently made) point, but I wanted a simple old-school setup, AND I don't feel like plowing another 2 grand into EFI (and doing all the associated fabrication). It would be nice to be able to tune from a laptop instead of: drain bowls, remove fuel line and four bolts, remove jet/bleed, drill a new one, installation is the reverse of disassembly! I've already had a "helpful" person tell me to get a smaller cam, too rolleyes

I tried going up to .033 on the primary MAB. Not sure if it helped (no dramatic difference). Cruise at 3000 rpm, 15" Hg still 12.5:1, and accelerating moderately (10" Hg) still 14:1. There is a lean flat spot at tip-in that I don't usually hit anyway, but 30 mph 2000 rpm cruise is 15:1 smile

Also I leaned out the idle screws 1/4 turn to an indicated 14.5-15:1... same vacuum and RPM, and I don't think any lumpier, so that was probably too rich also.

Might try enlarging the MAB some more, say .036 and see what that does. work I really want to get the 3000 rpm cruise as lean as possible (like the 14-15 with my 800).


Wanting to have excellent street manners and race car performance is a difficult goal to accomplish.
When you start making compromises or concessions to one , the other will suffer.
My " street " toy is a 12.85 :1 , E-85 swilling solid roller and carburetor having bundle of joy.
There are some driveability issues that I live with , because when I push my right foot down with enthusiasm , I quickly forget that little stumble on tip in.
You can get them close , but I have yet to see perfect.