Anyone have any suggestions? I have AFR 180 heads (needing a gasketed plug). I have some form of discontinued iridium plugs in it now, and am in need of replacing them. Autolite 103's were suggested, but they are not a gasketed plug, and thats what I need. BTW, am running a D1SC at 15-16#'s of boost on my 383 in my sig.

 

Basically what plug is equivilant to an Autolite 103 that has a gasketed seal for an AFR head?

 

AC Delco FR1LS

 

I am wanting to stick with an Autolite plug here. I've got it narrowed down to either an Autolite 3922, or a 3923, but I'm not sure which one is the same heat range as an Autolite 103.

Does anyone know? Or know which I should run based on the approximate boost level (15#'s or so) I am at??

 

put the 103 in you will be fine..

 

Dont use the 103 I recomend using an NGK race plug I beleive the
739-R5672A8 is the same heat range as the 103 or you could go one colder and use the A9

 

I second this, a lot the big HP turbo guys run these plugs and swear by them.

 

Guys, I can't run the 103 because I need a gasketed plug for my AFR heads. The 103 is the ideal heat range, but I need to go with either the Autolite 3922, or the 3923.

Between these two plugs, which should I run?

BTW, I don't want to run NGK's.

 

I ran the 3923 before I switched to the NGK R5672A8 and picked up over 20HP at the wheels.

 

The 3922s are colder than the 3923s. Try the colder plug and see how it does. If it fouls, go one step warmer. However, from what I've seen, you want the NGKs...same price as regular plugs...R5671A-8 even colder, prolly not req'd. R5671A-7 cold. These are flat seat plugs and are properly designed to disperse and dissipate heat in high performance engines.

Just checked. The 71's are non-projected. The 72's are projected nose. Otherwise, they're the same plug.

 

A good thread http://web.camaross.com/forums/showthread.php?t=431689
We run NGKs 7 heatrange

 

I run the 3922's with 10#. No problems, but will try the NGK R5671A-8 next. Good Luck...........John

 

thats whats in mine

 

I just picked up a set of the 3922's. Thanks for the help everyone.