Does anyone know what the spark plug numbers are when installing a Vortech on a sedan ? I think you need to change them to a different heat range when installing the supercharger but the instuctions say to change them if more than one year old but does not say anything about heat range .

 

One step colder is what most guys are doing. My sedan was brand new when I had the Vortech installed so I just left the platinum plugs at the time. But I'm approaching 5000 miles on the supercharger so I'm going to go with Iridium one step colder.

--Steve

 

the NGK stock no. is 3672
no. on the plug...LFR6A-11

I just came home from the dyno i'm thinkin' no matter which plug you use it will still be advantageous to upgrade the ignition system to MSD. No real problems but the dyno graph gets a little irratic past 4500 rpm.
good news was 323.2 HP 289.9 Lb. Ft torque
250 hp@3200 rpm WELL TURBO BOYS ???