my 84 truck with 1990 roller 302 cutting out bad at WOT
 

I have an 84 F150 that i put a 1990 roller 302 in that is out of a crown Vic. I have always had a problem since I got it running this summer when I would mash it to the floor it would start popping out the exhaust and cutting out. I was thinking it was the carb so I got a new holley 600 and it does the exact same thing. I have checked the timing many times and changed cap and rotor plugs and wires. I was told I had to get a distributor out of a 85 mustang because of the roller cam. I bought a reman from Napa. Could it be something to do with the weights for the advance being that it's for a light weight car? I have ran out of ideas.

Sounds like a fuel delivery issue. Does it run really good for about 3 or 4 seconds, and then start throwing a fit? That would be a sign that is has used all the fuel that's in the carb, and the fuel pump/filter or something in the fuel system is not filling the carb fast enough.

no it's just as soon as I mash it to the floor. It was real bad but it got better after I disconnected the vacume advance. It also seems to do it more when the engine is not fully warmed up. I am running about 12-13 degrees timing right now. When I had the vacume advance hooked up the most I could run for timing was like 0-2. Are the weights differant for the cars maybe?

Go ahead and set the timing by road testing, and see if you can get it to run good. I did this same swap in my 80(the first engine I had in it) and I can't remember the details of the timing pointers and front covers, but it may be a situation where the pointers and the harmonic balancer don't match, which would throw the timing marks off. Also on not so rare occasions, the harmonic balancer outer ring will slip, throwing the timing marks off.

Water in the gas run 2 bottles of heet and 2 bottles of iso heet. The methanol sinks
and removes the water sitting on the bottom of the tank and the isopropyl gets the water in solution. I would also take the fuel filter off and fill it with iso heet so the
fuel system gets a blast of it to grab the water. Try that before doing anything
drastic.

Good call on the fuel filter...mine was crappin out same way and i pulled off the filter...
it looked like it was full of black coffee
ran tons better aftera new one that.

I tried a new filter also. Ran many bottles of heat too. I just think it's something with the ignition

You need a good smooth advance curve in which your mechanical advance is coordinated to work with your vacuum advance.


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