engine miss??

I have been getting a miss in my engine...351C with a stock 2 barrel carb. Runs great at idle and then with or without a load as I rev it up it seems to get a miss and runs a little rough. I replaced the points,condenser and ballast resistor....plugs are light brown...almost look lean. Could this be a slightly plugged passage in the carb?coil going bad? clogged fuel filter? any other things I should be looking at?

 

look for a manifold vacumn leak or an open port.

 

Sounds like you have an ignition wire breaking down. When`s the last time you put plugs & wires on it? The more rpm, the more kv[juice] that`s going through the wires. Very common on the Fords.

 

Timing??

 

and when all else fails, check the valve springs.

 

my 289 did that, and I had a broken valve spring. it was still atached, but it was kinda flattened. did a wick valve job, new springs and it ran great. My SBC 350 I had a miss, and popped the hood at night and when it was in gear, with a friend holding the brake you could see the arcing where the spark plug insulation was breaking down.

-Sobastrace

 

Check the fuel filter first. It's cheapest to replace. Coil breakdown usually occurs when under load. You can wet the wires and look for the spark as said before, but I'd think that a bad wire would either work or not.

Flatman

 

Timings spot on ( I usually check the cheap stuff first!) I will try the wires next as I have searched for vacuum leak already......I may change the one hardened vac line while I am at it. Thanks for the ideas!

 

Got hydraulic lifters?

You may have one or two too tight.

A compression check can tell you what's up there.