Inliners International Forums General Discussion Engines missing while at slower speeds

My truck starts fine and once it is warmed up purrs great for about 30 seconds and then has a little hiccup, then runs good again, then the hiccup and so on. It will run great at about 45-55, never drive faster than that, but while driving it at slower speeds like 30 it has a constant miss. Just sputters away. I can put it in 2nd and let it idle down the road it just sputters and wants to buck on me. There is also has a hesitation when I take off from a dead stop. While at a light it purrs with no hiccups. Any help on where to start would be great. The engine has about 500 miles on the rebuild and everything is pretty much new, dizzy, coil, points, plugs, wires, carb, intake , etc. I did a search but couldn't find anything that may help. Thanks.

stock intake/exhuast and ignition?

I am running an offy intake, Holley 350 cfm 2bbl, stock 2 1/2" exhaust manifold, and stock ignition. I have a convertor from 24v-12v that runs the ignition.

It was running great when I first got it going and driving it often, then the miss just showed up. Fuel filters are all clear, checked those last night. I also checked all the wires for any chaffing or rubbing.

What color are the plugs??

I didn't get a chance to pull them last night. Only had time for a quick visual. I will pull them tonight if I get the chance and post back.

do you have enough heat to the intake? does the heat riser work?

Okay; do that and re-check your valve adjustment(s).

When the valves seat, the lash becomes less and sometimes they can't close competely etc.

Good luck.

The plugs look great. The valves seems like the next place to look at. I will readjust them this weekend.