427390

I have a 69 427/390 with a comp cam, Edelbrock intake and headers as well as stock heads and stock bottom end.

The #6 cylinder is showing some oil fouling (but definitely still firing as confirmed when I pulled the plug wire while it was running) and I see a bit of smoke coming out back but only when I really floor it

I am running AC Delco Rapid Fire #4 plugs in the stock oval port heads. My question is can I run a hotter plug in the #6 cylinder (or all cylinders) to do a better job of "burning the oil"? I know it sounds a bit bubba, but I am looking for a quick/low cost way to avoid tear down until winter. If so, what plugs and heat range would be recommended.

To save some questions 1) I have not done a compression or leak down test 2) the car runs pretty strong despite the appearance of oil on the plug 3) I have cleaned the #6 plug and it clears up for a while.

Thanks - Joe

V77Vette

synthetic oil will help (if you have dino oil now)

Retro78

Try a MSD box.

stingr69

Bubba would use an anti-fouler adapter for the #6 spark plug.

Try some Autolite hotter plugs while you are at it. The heat range seems broader to me on those.

-Mark.

427390

any specific heat ranges that anyone could recommend? I think the stock spec plug is AC Delco R43 xls...?

capevettes

I run R45XLS in my 68 427/390 and it runs great. NO fouling. I like 5 heat range plugs in big and small blocks. I would try them but you may have an underlying ring or valve seal problem.