Originally Posted by 70nova327
checked vacuum its great, between 10 and 16 at idle, checked fuel pressure and it was at 8.5 so im off to get a regulator, started to advance the time and the engine the engine sounded beautiful but then started to rock, i noticed that my glass fuel filter was only a 1/4 of the way full, vapor lock because of the intake air bypass? but then i randomely unplugged the dist advance at the carb and the rpms shot up and it leveled out the rock and ran amazing! why would this occur? did i just find the problem?
Hey Bruce, sounds like ur getting there, the engine started to rock once you went too far with the initial timing...when u randomly unplugged the dist advance, the revs shot up because you created a vacuum leak at the carb where the hose came off and then the 'rock' leveled out because the engine revs went up enough to deal with the excessive advance that caused the 'rock' in the first place.
When you disconnect the vac advance to set ur initial timing, be certain to plug the carby so it don't suck air. Easiest to take the hose off at the advance canister end and shove a screw or whatever in the hose to stop the suction.
Another way to check total advance with your timing light is to wrap some masking tape around your balancer, to measure the circumference, then take it off, measure it, and divide the figure by ten, this will be 36deg (360 divided by 10) make a mark on the tape at that measurement then put it back on and transfer the mark clockwise from the TDC notch on ur balancer. Next time u can check ur total by referring the timing light flash to that new mark when you raise ur revs to 3000-3500rpm
Hope this helps