non-resisted spark plugs/ hotter heat range

[0ldhaus]

I've been searching for a thread about non resisted plugs for my 72 350sl, but to no avail. I recall ngk plugs being recommended and a "bp" number butlittle else. Restoring a 125 year old house so sl has been back burner'd. I'd also like to try a higher heat range to see if they might burn cleaner. Any feedback would be genuinely appreciated. Thanks

[rowdie]

NGK BP 6 ES is what you are thinking of. BP 5 ES is hotter but normally run in cat equipped 107s.

[0ldhaus]

Thanks, Rowdie. I think what I have in now are b p 5 somethings. Going to be warm tomorrow so will verify what they are. Appreciate the help.