Thread:

Spark plug help

Originally Posted by namba860

I have a carbureted mild 502 with aluminum heads and dont know if i have the correct plugs in it. Im not sure whos cylinder heads they are. The plug that came out of it was an ngk vpower 8 they are a long reach with a crush washer on them. Any recomendations?

Thats about right. If the compresion is pump gas range you might try a 7. But almost all the aftermarket late alum heads use the .750 reach gasket plug.

Originally Posted by mdsheppie

Autolite 3924

Even Ford lovers don't run Autolites anymore.

Originally Posted by namba860

I have a carbureted mild 502 with aluminum heads and dont know if i have the correct plugs in it. Im not sure whos cylinder heads they are. The plug that came out of it was an ngk vpower 8 they are a long reach with a crush washer on them. Any recomendations?

Good spark plug... depending on combo may be a little cold... but a good refrence point. The stock number on what you have is 4554 (p/n R5671A-8) and is a fairly common starting point plug number. See what the engine likes... if it appears you need a warmer plug... go with a #7. Nice thing about the NGK plugs are they are fairly easy to read.