What Causes Spun Bearings?
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What Causes Spun Bearings?
Some people can rev a stock shortblock to 7k with no problems and others will spin a bearing with a stock rev limiter.
My guess is oil pressure loss during hard acceleration. In my car if its just 1/2 quart low in oil, the oil pressure drops while accerating in first gear. In second gear its fine.
So I am thinkin since these engines burn a lot of oil, it wouldnt take long before the engine is down a quart. Then the owner drives it hard without paying attention to oil pressure. It drops off at high rpms and some bearings get spun. Is this reasonable or is something else going on?
My guess is oil pressure loss during hard acceleration. In my car if its just 1/2 quart low in oil, the oil pressure drops while accerating in first gear. In second gear its fine.
So I am thinkin since these engines burn a lot of oil, it wouldnt take long before the engine is down a quart. Then the owner drives it hard without paying attention to oil pressure. It drops off at high rpms and some bearings get spun. Is this reasonable or is something else going on?
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I am just sharing my theory. I dont know if its right or not. For me the oil pressure droppin thing got much worse after the cam. I bet the motor would spin some bearings if I revved it to 6600 while the oil pressure is low.
Seriously, the oil pressure droppin isnt something you really notice if you got a manual trans. Youre too busy watchn the tach.
Seriously, the oil pressure droppin isnt something you really notice if you got a manual trans. Youre too busy watchn the tach.
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Originally Posted by Pro Stock John
If you are low on oil yah you can starve the bearings.
I was beating on my h/c stock bottom end in the bird spraying 150 back in 2000 and killed it on the 2nd bottle.
I was beating on my h/c stock bottom end in the bird spraying 150 back in 2000 and killed it on the 2nd bottle.