feeling a bit stumped 52 suburban running really rough

[martybose]

Don't all these heads use a 3/8" reach plug?

 

Jeff

All of the stock heads do, but not all heads.  I found out after a while that my Edmunds head was designed for a 1/2" reach plug, and had messed up threads because of running 3/8" plugs.  That said, I have no idea whether any of the other aluminum heads use 3/8" or 1/2".

 

Marty

[Don Coatney]

He is not answering an email?

Any one with the Langdon distributer - what plugs did you get sent/use

I have R44SX 

Try the telephone.

[58prostreet]

Yes, the 306 autolites are gapped at .060.

Bob

[52Suburban]

I kept thinking about this and having the same problem, so I tried something different - So the stock gap is .028 and the Langdon plug is .060 so it is .032 longer - they plugs have the same reach. So I found spark plug washers, designed to move the position of the electrode. I used one that is .032 and now the plugs should be higher in the chamber and rotated to the position they were at with the .028 gap but have the bigger gap for the HEI. The car is running great!!

Edited May 25, 2015 by 52Suburban