DanielRicany

Hello, AFR recommends NGK R41 CXLS for racing applications, and different plugs for street applications. I have AFR 195 heads and 10:1 Compression with a Miniram and supporting mods. Would I be okay to use NGK R41 CXLS if I do street/strip?

Thanks!

lt4obsesses

I don't know the exact answer to your question, but here are a couple of questions I would ask to get the answer you need;

1) What is their definition of a racing application?

Many racing applications are set up to run a 100+ octane race fuel, and tend to run higher compression ratios, unless using forced induction of course. Perhaps these plugs are not designed for the lower 91-93 octanes at the pump? A 10:1 is not radical of a ratio for a SBC.

2) What is special about this plug that it is recommended for racing applications and not for street applications?

The plug may have a different temp range that is suited especially for race engines to prevent spark knock or detonation, which would be really bad in a high rpm, wot situation. However, for street driving, it may not be well suited.

JackDidley

Sometimes a racing plug will cause RF noise in your stereo.

DanielRicany

How about NGK BKR5E?

JackDidley

Try the NGK site. Race plugs and resistor plugs.

DanielRicany

I used NGK BKR6E.

Originally I wanted to use BKR5E, but I did some reading and opted to go 1 heat range hotter.

I messaged Tony Mamo at AFR about BKR5E and he said he thought it might be too cold for a street car.

I used BKR6E and took it for a ride, no overheating, nice exhaust sound and nothing out of the ordinary so far.

Thanks!

DanielRicany

Whoops. Looks like I actually went one step colder. Oh well, my plugs were a little on the white side anyway. If anything happens I guess I'll just change them again. Other people with AFR heads said they use these plugs.