Let me start off by saying I know nothing about spark plugs. My engine is 13-1 compression, TA Stage2 SE heads and I'm burning C12. I have been running the NGK R5671A-7 plugs. While I was in Cecil my buddy Matt was reading the plugs and he said we need to go hotter. The 7 heat range is the hottest for the series plug I'm running. Any suggestions? Thanks,
I am having buddies over here run NGK 9 with their nitrous stuff, dont know if they are any good for your combo?
I run the NGK R5671A-9 which is a hot plug or -10 which is cold. Or my best runs have been with Autolite AR 3934. This is my suggestion for good air. What ignition do you have? I have a 7 AL3 with MSD dist.
Mine is N/A and yes I have a MSD 7 with a crank trigger. I think the -7 I'm running is the hottest plug in the R5671A series. I wonder if the NGK7373-FR5 is hotter than my current plug. I'll also check on those Autolite plugs. Thanks,
The Autolites are clip gap which should take some of the need for a super hot plug away. I am NA also, same compression, same ignition etc with my old engine. You need new plugs every trip to the track. Where do you have your total timing?
Don't know if it applies to the NGK race type plugs, but NGK plugs get colder the HIGHER the number, so you would need a lower number than 7. https://www.ngk.com/learning-center/article/200/how-do-i-find-a-colder-or-hotter-plug
That is correct Larry the higher the last number the colder the plug. In the series of plugs I have been running 7 is the hottest plug. I guess I'm looking for something in the 5 range.
From what I have read it doesn't seem right to me either but I don't know anything about reading plugs and I have the utmost confidence in what my tuner is telling me. I still have 3 or 4 sets of the -7 to use up and a set each of the -9 and -11 heat range. But was wanting to get something hotter for the next TnT session which will probably be BG.
I have always had excellent results using Champion Racing Plugs, as I spent a lot of time talking with their Tech Dept. but I don't believe their heat ranges reach high enough to exceed the NGK's. The Champion C59YC is what I have been happy with and their series goes 59,61,63,65. The 65 is their hottest in that configuration. Larry
Wizard, can you find the post Tom Rix made on here about reading spark plugs? Lots of valuable info there. I printed it years ago and have it somewhere but cant put hands on it.
http://wallaceracing.com/plug-reading-lm.html Best article I have seen on reading a spark plug. The 7, 8 or 9 is typically good for the Buick engine. Backing off a bit on the timing may help.
