Hey guys I'm looking to see what plugs I should be running in my engine.I am also looking for a conversion chart to see what plugs are the same in NGK,Champion,AC delco etc.

502
edelbrock aluminum heads
9.6 to 1 comp
850 demom carb



Thanks Nordic95

I think the edelbrock heads are the same as the GMPP aluminum heads. If they are i am using the ac delco R43XLS.I got the NGK which were a little cheaper but did not notice any differance what so ever.Hope this helps

My engine builder installed Champion RN9YC and the conversion at the auto parts says to use Delco R44XLS.I have always liked Deco better then Champion but I would like to know what the equivlent is in NGK.Is the higher the number the hotter or colder in A/C Delco?

Thanks Nordic95

In Champion and AC the higher the number, the hotter the plug. The opposite is true in NGK. Don't forget to use anti-seize in the threads with your aluminum heads.

I use AC delcos Rapid fire 1 get results last for two -three seasons. I use them on supercharged applications along with natural asperated. I used njk thought the performance was bad, fouled plugs.

Im not sure about the heat ratings but i was wanting to go 1 range hotter but have not gotten around to it this summer. I have 10.7:1 compression and several people have said i need to go hotter. Any truth to this?

Champion plugs suck. I blew the the electrode right out of one once. I thought I blew the engine. The electrode was still attached to the plug wire. I won't even use them in a lawnmower anymore.

I don't think so. Usually with a high compression engine you need a colder plug.

Remember the terms "hotter" and "colder" refer to how much heat the spark plug tip RETAINS, not how hot the spark itself is.

The trick is to get a spark plug that is hot enough to resist fouling at extended idle periods, but not so hot as to cause detonation because it is glowing at high speeds. Start out colder as you will be much less likely to cause damage. Learn how to "Read" your spark plugs. They have much information about your engine.

I have never had much luck with Champions either. Once I had an old timer tell me to throw them in the water and only use the ones that floated.

Anthony,

Attached is a master cross reference spark plug chart compiled in excel format. It is absolutely the most comprehensive resource I have found. i have personally uploaded it to Mediafire and it is guaranteed virus free

Tip on use of this sheet:

Be sure when you cross one plug brand to another you scroll the list completely! Reason being, the listed companies have varying plug designs available that cross to another company.

Example: A Champion product "R1234" may cover multiple generic apllications, whereas NGK may have more specific designs and multiple part numbers that over same range depending upon the specific application.

Apologies for not listing the source.

Bob
http://www.mediafire.com/?1mt9dz4mww9