I have a question I just built a Chevy 383 stroker mild cam, stock crappie heads which I will soon change but I converted the ingition to HEI. Does any-one have a suggestion on plug type and GAP as there is a diffrence from the old points gap .035 I have seen high HEI gaps .065 and higher.Has anyone used shorty plugs for headders, Good, Bad, No Diffrence?

Any help would be Great.

You need to identify the heads, the sparkplug has to start with what fits the heads in terms of thread size and length, as well as what kind of seal being taper seat or gasket. Given that you said you're using "crappy" heads I take it to mean low compression in which case pick a heat range that fits the engine the heads came from. You can adjust to a hotter or colder plug later on if they're not right on.

Extra wide gaps with HEI serves no purpose, something in the neighborhood of .040 is plenty good.

Shorty plugs work well with headers because they provide enough clearance around some of the tight tubes to get a socket over them making installation and removal eaiser and less likely to damage the insulator. Other than that, they function just like a regular plug.

A thing called "O rachet" available at Sears and other places, makes doing plugs under headers a whole lot easier as the plug passes right thru the wrench, thus the wrench will fit in tighter places than a conventional socket and ratchet combination.

Bogie

      Thanks  OldBogie,

         As fo the crappie heads they are just the cast iron boat anchor heads small ex1.50- in1.94   5/8 straight plug.They are fresh thoe, just rebuilt that was all I could afford at the time BUT some day I'll get a GOOD set on the 1970 Monte Carlo 383 sleeper to help wake up the motor as it seams to be a MUST on a stroker gotta breath .I'm looking if any one has any they are wanting to let go reasonably priced.

Once again Thanks OldBogie and any-one else that can help.

Check out your compression volumes, some of these smogger heads will conspire to run the compression up pretty high on a 383. Better to know going in than after it's together and pinging.

Bogie