Spark plug gap for mild Buick 350.

[MrSony]

The stock plugs for the engine according to the internet (scan of a shop manual from back in the day that I found)
says AC Delco R45TSX plugs at .060 gap with HEI. Should I run a smaller gap with my .469/.469 cam, qjet and modified HEI? I've heard a gap that big causes problems with HEI distributors and that .045 is better. Or does it not matter at all for a street engine? I have Autolite 25s in it and I believe they dont burn as well as the AC's would. What say you guys?

 

[pontiacgp]

The only real way to tell is to put it on a dyno with different spark plug gaps. Start off with a small gap and work your way up till you find which gap gives you the most power. And do that with different brands of plugs so you can find which plug gives you the most power. Don't forget to index the plugs as well.

 

[Qdub24]

There is a wealth of Buick knowledge over here: v8buick.com

I know there's a difference in gap sizes between points and hei distributor setups.

http://www.v8buick.com/showthread.php?307768-Spark-plug-gap-setting&highlight=Plug+gap