1978 ford 4x4 running problems

[mitch1500]

i have a 78 ford 4x4 f150, its got a 351m to a 400. i got the truck not too long ago, and drove it for a couple of days and it started spuddering, so i timed it, put new plug, wires cap and button. and it kept on spuddering wen i drove it, it would idle fine but wen u put a load on it it would spudder, so i put a edelbrock 650 on it and it did a lil better, so i checked the vaccum advance and it was moving the distributor thing like it should, im not sure what the problem is, could it be fuel pump, coil or sumthing else,

 

[d-kuzmen]

If the distributor has points in it I would change them and it could also be the coil not being able to put out enough voltage under a load.

 

[blacksnapon]

i have a 78 ford 4x4 f150, its got a 351m to a 400. i got the truck not too long ago, and drove it for a couple of days and it started spuddering, so i timed it, put new plug, wires cap and button. and it kept on spuddering wen i drove it, it would idle fine but wen u put a load on it it would spudder, so i put a edelbrock 650 on it and it did a lil better, so i checked the vaccum advance and it was moving the distributor thing like it should, im not sure what the problem is, could it be fuel pump, coil or sumthing else,

Because the addition of the carb reduced the symptoms, I'd look at fuel delivery. Such as power valve, accellerator pump, or fuel filters.