I wouldn't go above 150ish with nitrous. Why the timing problems? What ECM are you using? I have EFI, have done EFI on many, many combos, only one ever gave me problems, it was just the plug wire/ non resistor plug combo...... I run non-resistor plugs all the time, no problem. Those plugs may be too hot. With EFI you can certainly run a nice cold plug and have no problems with them.
How hurt is it? Plug pics, very large!
2
Was out goofing around the other night, things seemed OK. Race a car with very loud exhaust, two races. Nothing too exciting. Drive home I romp on it once and it's pinging like a MO-FO! WTF!? Somehow decided to go for 40° timing. I finally got around to pulling the plugs tonight and crap.. Speckles on most, porcelain eroded off others, rainbow on a couple straps. Here's two samples. What's with the speckles? and what causes the porcelain to erode like that around the positive electrode?
I compression tested it, 145-160 all around. Thinking about borrowing a bore scope. What should I expect to see? You guys think it's hurt?
Pictures not resized smaller for better clarity. Note: I use bronze looking anti-seize, that's not rust. And my drive home was 15-20 miles of in town driving, so the mixture is/was all over the place for the rest of the discoloration.
Speckles:
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Porcelain erosion:
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I compression tested it, 145-160 all around. Thinking about borrowing a bore scope. What should I expect to see? You guys think it's hurt?
Pictures not resized smaller for better clarity. Note: I use bronze looking anti-seize, that's not rust. And my drive home was 15-20 miles of in town driving, so the mixture is/was all over the place for the rest of the discoloration.
Speckles:
Porcelain erosion:
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I am only talking about full throttle. At part-throttle run that baby 14.5 to 15.0 A/F, as lean as you can and with as much timing as you can. If you have trouble with tip-in and can't get it right with the accel pump then run it fatter 'till you like it. 
That's the beauty of EFI, we can do whatever we like with timing and fuel at any rpm and load on the engine.
That's the beauty of EFI, we can do whatever we like with timing and fuel at any rpm and load on the engine.
1 - 3 of 15 Posts
