Hi,
I have 1972 Dodge Power Wagon, it doesn't run much. Well we had a used engine put in it. Well I been having issues with it since. It back fire constantly, no power at all it idles and back fires. I good oil pressure, plenty of gas, and my carburetor is good, and the my distributor is not lose. The timming chain was check a while back.....

Do anyone have a suggestion??

 

Are you sure the distributor is good? I would start there.

 

Check the tune-up.... Spark plugs, Wires, Cap, Rotor, Points, Condenser, Coil, and wire....
Dead time the engine back on number one cylinder and make sure all is well with that setting...
Keep us posted.... Cheers

 

I think its timing for sure