Spark knock or lifter float? (under heavy accel)
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Car: 1984 Camaro on steroids/ 1987 iroc-z28 5 speed.
Engine: 383 nitrous motor / poindexter 305
Transmission: Th350
Spark knock or lifter float? (under heavy accel)
I have been experiencing a sound like metal marbles in a can for about 3 seconds under heavy acceleration, then it goes away. I thought it may be spark knock, so I am going to start using premium. However, I was talking to a guy who said that it could be lifter float for a second or two under accelleration, until the oil pressure got to the lifters. I dont like the idea of my lifters smacking my cam or pre-ignition. Has anybody experienced these symptoms? The sound is pretty loud when it happens, but like I said, its only under load and for a few seconds.
A few notes- I have disconnected the EGR valve and air pump. Would this lend itself to spark-knock? My comp. isn't throwing any codes.
A few notes- I have disconnected the EGR valve and air pump. Would this lend itself to spark-knock? My comp. isn't throwing any codes.
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Car: 4
Engine: 6
Transmission: 5
It's not "lifter float". There's no such thing.
The lifters don't "smack into" the cam. They're up against it, 100% of the time; the valve springs keep them there.
Oil pressure doesn't "get to" the lifters during acceleration; it's always there.
It's spark knock.
Back your timing off in the smallest possible increments, unitl it quits.
The lifters don't "smack into" the cam. They're up against it, 100% of the time; the valve springs keep them there.
Oil pressure doesn't "get to" the lifters during acceleration; it's always there.
It's spark knock.
Back your timing off in the smallest possible increments, unitl it quits.
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