[jayman306]

I Have A 408 10.5 Compression With A 4150 Hp 750 Cfm. I just bought the edelbrock 70021upgrade kit and was wondering what spark plugs should I be using? The plugs in it now are auto light 3926. Should I go to the 3923 or 22? I'm running a 150-200 shot threw it. Thanks in advance

 

[dreday98781]

I run non projected NGK -7 on on motor and -8 on a 150 shot

 

[93reefbluegt]

i run a NGK BKR6e on motor and a non projected -10 on spray with a 150 and 175 no bigger yet. im sure its much colder then need but it has worked great so far with 116 on the standalone and a mix of 116 & 93 in the tank. when going to a hotter plug is there really power to be picked up or is it better for dialing in the tuneup?

 

[Induction-Solutions]

You need to go to a NON extended tip plug like the NGK R5671A-9. Thanks, SJ