Spark plug?

I posted this over on 460ford.com but didn't get much help so here goes. 557 race gas motor 13:1 with dominator run 110 fuel. I currently have ngk v-power 10's and wondering what you guys recommend. Is this good for my combo a guy over there said it was too cold a plug for a n/a engine. Also, heads are the iron d3ve-a2a heads. I've never ran engine yet bought a few months back and these plugs are pretty black from car sitting and just being idled in shop so I need new ones just want to get best ones for my app.

are you spraying the motor ?

No it doesn't have any power adders and timing is set on 32/33 with 110 race fuel.

That's a really cold plug. The coldest plug NGK offers in this size is an 11, so you're right there at the cold end of the scale. I was running 11's and they wouldn't last more than one race and then foul out. Even with the spray!

I'm now running 9's, and they seem to work good with the 200 shot and off the bottle as well.

If you're not spraying, I'd look to an 8 and then see how the plugs look.

Greg

-10 NGK plugs are to cool IMO.

I'd go with a -8 or equivelent Autolite Racing plug. What is the complete part number on the plug now? I have a cross reference and can look it up for ya'

Thanks

The number is R5674-10 came off of plug.

I don't have a R5647-10 on my cross reference. I have a -6 and -7 that cross over to AR12 and AR13

i just added a spark plug reference chart above in a sticky ^^^^^^^^^^

bruno wrote:i just added a spark plug reference chart above in a sticky ^^^^^^^^^^

Similar to the one I have, it's on the Autolite website

What Gap are you running with that comp.?

The projected tip of the 5674 should be good n/a.

On the spray the non-projected tip of the 5671 seems to be preferred.

Greg

ar 12 seems to be the closest to the ngk 8 heat range. Should I just go with the ar12 or maybe just try the ngk 8 plug?

Fast Fox wrote:ar 12 seems to be the closest to the ngk 8 heat range. Should I just go with the ar12 or maybe just try the ngk 8 plug?

Either one will work. I've used both AR and NGK and have no complaints

Sounds great what is the recommended gap?