Adrian Worman wrote:Do you run a vac can on the distributor? The only way I can get a clean exhaust at idle on my fairly mild 440 is to run manifold vac to the dizzy. I can't see how you can run on the street without it
I agree Ade! Pat,,do you have open chambers, (they need more timing), do you have early/late intake timing events,(240 degrees or more @.050), more initial timing also need,,whats the idle vacuum and is it fairly steady at idle? Bigger cams show the needle fluctuating but not wildly. Anything below 14" is gonna need 18-24 or more of initial. Is the timing stable,,I'm going to order a Shaft Collar for my distributor,,they seem to work well and help stabilize the timing curve. Having a richer mixture kinda helps confirm you might need more initial? Richer mix burns quicker. What do the plugs look like? If all this checks out,,then I would look into the carb inner workings,,have you tried holding a finger over the high speed air bleeds at idle,(the closest one to the center of the carb),,does it pick up revs when you do this? Hope you get it figured out Pat,,oh yeah,,no gasket overhang or anything like that,,I think you have been thru them a few times,,nice custom work Pat!
I too use ported Manifold Vacuum on my 440SixPack,,starts right up,,idles very nicely,,12" vacuum nice throttle response,,,I use the Pro-Max metering blocks and rear billet adjusatble base plate. I have 20 initial,,14 Mech. Manifold Vacum FBO Dizzy with 12 degrees vacuum in the Vac. Pot.