Join Date: Sep 1999
Location: Casa Grande, AZ
Thanked 0 Times in 0 Posts
Re: Should indexed spark plugs face head or piston??
[ QUOTE ]
Waste of time and plugs!!!
did it to a mustang after a dyno run, and got NO differece on the second series of dyno passes.
[/ QUOTE ]
It depends. I know the guys at a local engine shop, they have an engine dyno and the chief engine builder builds mostly V-8s for drag racing, and he does index plugs with gap pointing towards the piston. In a daily driver or non-race applications you probably won't notice any difference.