Hey fellas....Im in kind of a bind here, trying to get my girl running again.

I have no idea of what type or reach plug should be going into my 781 heads.

Anyone have a part number in Delco? Im probably going to run a 44, but I need to know if it is the large or small socket, and what reach tip etc.

Thanks fellas!

I run an Autolite AR13 which is in their racing plu series. It's an extended tip with a cut-back electrode. The 781 head takes a tapered seat/small hex plug.

Hmm off the top of my head i think its 14mm 5/8" tapered seat and standard reach. A set of NGK 7052's are your best bet.

-Ryan

Dave,
The ones currently sitting im my garage have R45TS in them.

I run AC Delco Rapid Fire number 2s on my 781s. They replace them if they go bad or foul or?