351W wont start

[kysard]

I need help here, I took the heads off my 351 and had a valve job done, I also replaced the chain, upgraded to a mallory distributor, and rebuilt the holley carb. I did this all at once. Put every thing back together and there is severe backfire (flames) out the carb. I have messed with it all day and am at a dead end. I checked cranking vacuum with the coil unplugged and I get ZERO vacuum. There are no leaks. I put the engine at TDC and took off the #1 rockers and noticed that the valves moved up when I did this. Is it possible that the head shop milled the head enough that I need smaller pushrods? Or do I need to pull the timing cover and check that the new chain is on right?

 

[mustangdave]

Backfiring through the carb, no vaccuum sounds like the timing is way off. If you lined up the chain right, you are probably off on the distributor. Try removing the dist. and turning it 180 degrees; you may be trying to fire on the wrong stroke, which can be deadly to an engine.

 

[blue66tang]

That sounds like the problem.

 

[kysard]

Problem was I left off the keeper bars for the rockers. Not done any ford heads before and the head shop didn't return them. It runs great now. I should probably replace the power valve in the carb due to the backfiring?