Alright so i am new to this forum and i am posting for a friend we need help baddly with his 1984 ford f-250 300 inline six. recently we did a one to 4barrel swap along with changing out the electric feedback system with a new points distributor, coil, wires and some other stuff. we ripped out all the electrical unneeded stuff and now it runs like poop. we used a brand new offehauser 4bbl intake manifold and a used 1406 600cfm edelbrock carburetor which even tho is used i know it works because it was off of my truck. now his truck starts but hardly runs the timing is close but is hard to get spot on because it jumps up and down because the idel constantly changes and when driving it surges or jerkes you back and fourth we moved the jet sizes on the carb down three sizes and the 1406 is an already leaned out carb so i figured it would work the plugs are a little white and it isnt really running rich in my opinion. we set the points with a match box and the timing is around 10*. my knowledge to this is limited i know my way around an engine i have built a few but im unsure of why it barely runs drives a little but if not being floored or going down hill it surges like crazy and backfires. wont go up any hill at all and that’s where we live in the hills. so any feedback will be greatly appreciated if you have any questions feel free to ask thanks.

 

Manifold tight? It sounds like a vacuum leak.

 

yes manifold is tight we just tried to slap a 2bbl on there that carburetor is new and it idles a little better but is doing the same thing as before.

 

Put the #1 piston at TDC on the compression stroke, the timing marks on the harmonic balancer should line up at the 0° mark... verify that, verify your ignition timing. Balancer may have slipped.

 

i actualy already did that turns out the timing was a few degrees off and the 600cfm carburetor even being moved down on jets and metoring rods was completely overkill we finally got it to run today with a 2bbl carb from a dodge 318 thanks for your guys help today i appreciate it.