Ignition timing and piston rings...
Originally Posted by Joseph Davis
Sewell, Blundell, Xeno, I, and others do.
My main mojo that I can lay on you, that I don't hear *anywhere* is that sometimes the plug looks like there's trash on it but it's just from a misfire or wear. The definitive answer is looking at the face of the piston witha bright flashlight; if the carbon coat looks like you've poked holes through it with a pin, so that you can see pinpricks of shiny aluminum, you are experiencing detonation and timing needs to be backed off in that cylinder.
My main mojo that I can lay on you, that I don't hear *anywhere* is that sometimes the plug looks like there's trash on it but it's just from a misfire or wear. The definitive answer is looking at the face of the piston witha bright flashlight; if the carbon coat looks like you've poked holes through it with a pin, so that you can see pinpricks of shiny aluminum, you are experiencing detonation and timing needs to be backed off in that cylinder.
Good to know. That makes sense.
I assume a good penlight would work well for peering into the combustion chamber? A borescope would be awesome, but being a full time student won't allow for such expensive toys.
I really do need to play around with reading spark plugs and det cans. I built a det can setup, but have only used it once.
Any good way to determine optimal ignition timing off of the dyno? I assume that reading the spark plugs alone will not yield optimum results. Is this correct?
I generally seem to get a pretty solid tune on the street. Keep in mind that I pretty much only tune NA cars.
that dragstuff link and the others at the bottom is them.
I got it thru www.yellowbullet.com a very big drag racing web site.
Lets just say Billy Glidden and J. Hump are memebers, ALOT of varied knowledge there.
I got it thru www.yellowbullet.com a very big drag racing web site.
Lets just say Billy Glidden and J. Hump are memebers, ALOT of varied knowledge there.
Originally Posted by snm95ls
I assume a good penlight would work well for peering into the combustion chamber? A borescope would be awesome, but being a full time student won't allow for such expensive toys.
Originally Posted by snm95ls
Any good way to determine optimal ignition timing off of the dyno? I assume that reading the spark plugs alone will not yield optimum results. Is this correct?
Originally Posted by Joseph Davis
borescopes are needed for some cars where either the plug entry is at a wack *** angle or you can't stick your head in there (scooby) but for a normal B or D I wouldn't use a borescope even if I had one. Straight drop in on the piston crowns, use a good power LED pen or flashlight and FTW!
If you define optimum as your engine doesn't come apart and you get 90%+ of possible power, then reading plugs works.
If you define optimum as your engine doesn't come apart and you get 90%+ of possible power, then reading plugs works.
JD, thanks for the replies so far. I would buy your *** a beer, but I doubt I'll be out to the east coast any time soon.
Is watching the fuel consumption a good way gauging what the engine is wanting for ignition timing. Say you get the A/F stabilized to a safe range, add ignition timing and the A/F gets leaner. Add timing until this trend stops. If you add timing, and the A/F gets richer, then pull timing.
Is that correct?
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