HEI conversion spark plug questions
 

I have a 72 c10 350 I'm swapping over to HEI and I can't seem to find a definitive answer in whether I should swap plugs or regap my stock plugs. If it matters, I'm running an aluminum intake, holley street dominator, and a mild cam (everything else is pretty stock). I'm sure this has been answered before, just can't seem to find it on here.
Any help is greatly appreciated
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Re: HEI conversion spark plug questions
 

Re-gap to 0.045" will be fine.

Re: HEI conversion spark plug questions
 

when I swapped to an HEI I simply regaped to .045 and changed out the plug wires to larger gauge. 8.0 or 8.5 I don't remember.
if your current plugs are in good shape you can always replace them later, then again no reason not to replace them as plugs are pretty inexpensive.

Thank you for the replies, I'll grab some quality wires and regap my plugs
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Re: HEI conversion spark plug questions
 

Late to the party but I agree with the above..... stock plugs, .045 gap, and HEI wires which IIRC are 8mm (stock wires are 7mm).

Re: HEI conversion spark plug questions
 

GMPP says use your stock plugs with an .038 gap for their HEI.

Re: HEI conversion spark plug questions
 

Hmmm, so which is it then? Someone had mentioned that i should do mine at .045 (which I did yesterday). Do I need to redo them all?

Re: HEI conversion spark plug questions
 

regap ,,, your plugs are specific to your heads

Re: HEI conversion spark plug questions
 

My engine is from a 78 so I gapped them to that engine, which was .043". Starts and runs fine, need to get to the carb next (oh and the exhaust and...)