I have an '82 Bronco that I replaced the 302 with a 351C 2V. I rebuilt the motor back to stock except an Edlebrock Performer with an old Carter AVS 4734. I also used the Cleveland distributor base with the guts from the 302 distibutor. Every since I put this all together I've had problems with the way it runs. Cruising down the highway its fine and it idles good (about 15 in. vacuum). When I leave from a stop sign or idling around town and step on the gas (gently) it misses on a few cylinders (almost sounds like a Harley) for about 30 yards until it clears itself up. If I tromp on the gas it usually from a stop it either coughs or does nothing for a few seconds and then roars to life. I was leaning toward it being a carb problem but today I built an adaptor plate at work and bolted on a Rochestor 2 barrel from a Chevy (yuck) 350 and it acted the same exact way.
I'm thinking about replacing the distributor because I noticed a fair amount of slop when I wiggled the rotor.

So my questions are:

When I go to the parts store, what year distributor do I ask for? I know the 351M, 400, 429, and 460 are interchangeable but what works with my 82 Duraspark II (the fender mounted ignition box has the blue plug if that makes a difference)

Also, do the Duraspark II components in the distributor wear out slowly or do they just go out all at once?

And finally, am I on the right track with my diagnosis or am I missing something? I'm great with old Volkswagens but I'm new to working on Fords.


Thanks for your time.

 

It sounds like a lean bog to me. Of course the carburettor gets blamed for all kinds of malidies caused by something else. In general the ignition system needs to be in good shape before tuning the carb. Also 15 in hg sounds low for a stock rebuild, to me at least, you might want to check for vaccume leaks.

 

The 351C/M/400/429/460 all take the same distributor. Ask for a 78-79 400 distributor but put a 1971 400 vacuum advance unit on unless you have polution equipment etc.

Something is not right with that low vacuum figure unless you have a big cam which is not "stock".

 

I've checked the top side of the engine for leaks but everything looked good. If it were leaking from under the intake, wouldn't it be burning oil? If not how would you check for that?

 

Maybe, maybe not. While the engine is running pull the oil filler cap and put a piece of cardboard over it. The PCV will pull enough vacuum to hold the card in place and it usually takes a couple of seconds to do so. If there is excessive vacuum you can count on an internal manifold leak. Ask me how I know.

 

slow in time will cause low vacuum.the dist,was the same from 74 to 85.from the time it came out till they went efi.

 

Well I picked up a new distributor, cap, rotor, and a set of intake gaskets today. Hopefully I can gather up the energy to work on it tonight. I'm going to concentrate on the vacuum situation after I get it running. Thanks for the input.