What is everyone using for spark plugs on the Pro Topline Iron Lightning heads? Ive been told Autolite AR144's and I checked and didnt find a part number. I also tried NGK FR5's which my dad said would not work. Does anybody have the right answer for me? Thanks.

 

According to their literature thye recommend a V59c as a starting point for those iron lightning heads.

This plug would be a good beseline on a race motor but is too cold for street driving and will soon foul.

A good street strip plug would be a Champion RV10YC

Or a AC R42tS.

 

thanks alot...Ive been getting frustrated lately with people telling me the wrong ones so I appreciate that. Yes Ive read their page saying that they recommend that but for some reason they only tell you plugs to use on 14 and 13:1 compression engines. So those 2 different plugs will work on a 10:1 CR engine then?

 

Do mean R42tS or R42LTS? I was told that the R42LTS works on the vortecs...

 

No R42TS that is a .460" reach.

LTS is a vortec and ford .708" reach. Different animal.


Yes that heat range is a good one for performance driving at 10:1 on the street.

If you want a non-projected tip plug get a AC R42T or champion RV8C.... Other than that the R42TS or RV10YC should be ideal.

This plug has always worked well for me over the years.

Its just a little cooler than a stock bread and butter motor plug.

Just enough to give some detonation protection At WOT without fouling up at idle and around town driving.

Gap them at .035" to .045"....and you'll be good to go.