what sparkplugs and gap
 

hey guys i'm building a 351 windsor stroked to 445 ci. it will have a ysi vortech sc making about 20 lbs of boost. would xp 3924 autolites be a good choice for plugs and what would be proper gap for that much boost. thanks for a response

Re: what sparkplugs and gap
 

I use the Autolite 3923's with no issues. With 20 psi and a good aftermarket ignition, I'd say try the gap at round .035

Re: what sparkplugs and gap
 

thanks for the response. i've got a set of xp 3924,s. is the 3923 a colder plug.