Hi all, Anyone have any tips on the best way to sync the carbs on a 1986 Interceptor? I have rebuilt all four of them, new jets, o rings, set the floats etc. Tried with the 4 vacuum gauge setup but didn’t have a lot of luck. One of the right side cylinders is popping when revs are held at about 4000rpm and no matter what adjustments I make, won’t fix it. Would be really nice for some advice before I gas myself in the shed with carbon monoxide, lol..... Any help greatly appreciated.
popping means too lean in most cases or bad spark. could be failed diaphragm installation, which would be apparent when revvvvving......... if a slide doesn't lift. otherwise, a too-small idle jet or fuel blockage somewhere, possibly a synch error or not. find which cylinder pops, then switch ignition coils to test. compare that plug to others, switch plugs around. best way for inital synch is with eye-reference to the throttle plate edge where it first begins to expose the first progression hole to sight. @4k you're in a transition phase from top of idle jet to needle position with an overlap of both.
Thanks for that, will have a look and see what I can find out. In the process of re setting the valve clearances at the moment. Cylinder 1 and 3 were a bit tight. Might have had a valve not closing completely on 3 prior to firing. Can’t hurt to reset them though. Thanks squirrel man.