Reply to "NEED HELP 351C won't run after new cam"

If you have 2v heads you need a 2v inlet manifold.

If your inlet manifold is a 4v it is likely not to seal properly on the 2v heads. This will cause all kinds of tuning problems.

If you want to use a 4 barrel carb on a 2v engine buy one of the many alloy aftermarket intake manifolds available that have 2v ports and a 4 barrel carb flange.

Also what harmonic balancer are you using ?

Is it new or is it the old original one ?

If it is the old one the outer ring may have slipped and the timing marks may now be in the wrong place.

Get number one cylinder (front left as you stand in front of the engine) to top dead centre on the firing stroke, look at the rockers and hold a piece of steel wire with your fingers in the spark plug hole if you have to and feel the piston as it rises to the top and pauses there , then check the marks on the balancer and see if they are correct.

One or two degrees out will be ok that is probably inaccuracy in you finding top dead centre but if it is 10 or 20 degrees out or more your balancer needs replacing, trying to time the engine from a balancer with a outer ring that has moved will be impossible.