So I'm a little bit of a bind right now trying to figure out what plugs to go with for my new engine main reason being is clearance for the headers! the factory AC's are almost touching them with no boots on. so here is what I have and I need the shortest possible to make my life easier

377 with dart aluminium straight angle heads
Edelbrock coated shorty air headers
10.7:1 static CR
in a 91 firebird vert
cant wait to be done!!!

I'm thinking that my best bet will be about 2 heat ranges cooler than factory due to my compression ratio but I do not know how having the aluminium heads will affect everything

also how much gap should I go with?

 

I have no clue on heat ranges, etc. - spark plug specifics I'm not knowledgable about. But My 350 has 10:1 dometops in it, and I HAD to use the Accell header plugs - not for the headers, but for the fact that they have less threads, and thus go less deep into the head. On my first crank, I had regular plugs for a 350, and the piston smacked the plug and bent the electrode! So you may need to consider compression chamber clearance as well as header restrictions.

 

thanks for the imput but my heads are the .750in tread depth so need to go with those and I have flat top pistons in it so I should have enough room in the chamber. however my question is still unanswered exept for the accell plugs. I still have no answer to my original question though especially since those accell's are not available in my area and a fortune to order into Canada