View Full Version : Tell me about my plugs

05-21-2013, 08:33 PM
http://i253.photobucket.com/albums/hh76/miikezj/Donzi%20repower/IMG_2441.jpg (http://s253.photobucket.com/user/miikezj/media/Donzi%20repower/IMG_2441.jpg.html)

This is after 30 min @ 3000 rpm in neutral to break in cam. Shut down immediately and plug pulled. Is this rich? Should I go run again when it stops raining next week then check after it's had a load on it? I got the whole Holley jet kit + power valves to play with. I havent dialed in timing advance yet, but it idles at 850 and 12 degrees.

Holley 850 on a 502.

05-21-2013, 08:59 PM
ya can't read a plug correctly just looking at it like that...

05-21-2013, 10:22 PM
well there is certainly some fuel on it but you really need to do a wide open pass and kill it and check.

05-22-2013, 08:41 AM
Plugs can and will in many cases look like krap until the rings take a set, it is far better to see them quite dark then light in color. Be happy they are dark! When you get about 10 hours clean them or put in a fresh set, like mentioned above run the boat about 5 minites @ 3500 then just shut the key of without decelerating. Pull a few check color I am willing to bet the results will be different. I have been following your break in thread and did not see any mention of ring break in, which is accomplished by several hard pulls. You need several full throttle take offs, babying a new build assures an oil burner, hard pulls will not hurt anything realize the only thing other than a flat tappet cam is ring break in. All else if put together properly is ready to run to its fullest capacity. Best advice never ever baby a new build


05-22-2013, 02:24 PM
They are gapped at .030 right now. Should I keep that gap when I clean them or go bigger?

05-22-2013, 06:49 PM
Plug gap depends on how hot your ignition is, if stock use stock specks. If you are running a real hot coil open the gap, I have run as high as .060 without an issue but my norm is .050 using a 60,000 volt coil.


05-22-2013, 07:42 PM
Looks like my specs are 40,000 volts. Should I open the gap? What is the advantage to opening the gap?

05-22-2013, 11:41 PM
Imo 035