Spark plug comparison

Does anyone have any direct dyno or track comparison between Autolite Race vs NGK Race plugs.

Current 598 has NGK R5671A-7 that my machinist installed.
It was ran on the dyno and last season on these plugs. Never tried any other.
My last two engines before this had Autolite AR3933, mainly because I can get them locally. The NGK's are not stocked, but can be ordered.
14:1 alky injected 598 BBF.

Any power to be had with one vs the other?

I doubt there will be any power difference that could be measured on the track. The NGK "8" or "9" should be more approprate for your engine than the "7".

We changed from the AR3933's to the NGK 9 on the dyno and there wasn't any difference. We only changed to see if the NGKs were easier to read. I have several boxes of the NGK 9s and AR3933 and 34s if you need some quick.

David i run the ngk-8 and have ran the 9 also.

I use NGK plugs to tune with, and run Autolites when my tuneups are solid. The Autolites seem to last longer, but I doubt there is any real measurable power difference.