Is there a relation between spun bearing and a cam installed...
09-21-2006, 11:46 PM
#1
Is there a relation between spun bearing and a cam installed... to an engine? I have two friends that I know that both have cam/s installed on their car and both spun a bearing. One is a LT1 z28 and the other one is 2V 4.6 mustang GT. Happened same month, within 2 weeks and the install was early this year. Does having a cam would give an engine a good chance of getting a spun bearing? Or is the install that did it? Both engines ran strong w/o any issues til it broke. LT1 ran 12.7 in a 1/4 and the GT ran 11.0x in 1000'.
09-22-2006, 07:22 AM
#2
Well it seems to be a problem with the LT1 the mustangs haven't heard anything about. I belive that you get the spun bearings because you are reving higher than stock the lt1 don't take it that well haven't heared anything with the mustangs but know the stage 3 VT cams want to rev way past what a stock block could handle and the stage 2 VT cams are borderlined.
09-22-2006, 11:47 AM
#3
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I have a theory. It's very uncomplicated.
The new cam'd motor sees higher RPM than it did with the stock cam. The user is revving more and higher RPM. As RPM increases blowby and ring wear increase. This can allow your oil level to drop off. Once you spin your motor to 6K+ RPM with low oil, bye bye bearing.
Ben T.
The new cam'd motor sees higher RPM than it did with the stock cam. The user is revving more and higher RPM. As RPM increases blowby and ring wear increase. This can allow your oil level to drop off. Once you spin your motor to 6K+ RPM with low oil, bye bye bearing.
Ben T.
09-22-2006, 11:54 AM
#4
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It also could be because improper motor break-in or even some installation problems. If the installer wasn't too careful taking the cam out they might've hit some bearings and caused damage. My real bet would be on the over-revving.
09-23-2006, 06:13 AM
#6
So you meant cam bearing not rod or main bearing? You didn't specify. Most people think in terms of the bottom end when you say "spun bearing" not a cam bearing. Never the less, a cam install should in no way be related to a spun bearing if due diligence is given during the process. That being said anything is possible and I guess you could damage a cam bearing if you worked hard enough at it. With reasonable care though this should not happen. If in fact you do have a spun bearing it has more than likely been caused by oil starvation than a careless cam installation.
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09-23-2006, 02:34 PM
#8
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Originally Posted by bene
I'm thinking its a cam bearing... All I know is both cars had serious knocks, backfires and low oil pressure.
09-23-2006, 04:17 PM
#9
FWIW, I had a spun cam bearing that I discovered on my 3rd cam swap. Old cam came out with stock cam bearing due to heat from improper oiling. That was a fun swap. 
I'm assuming the installer of the 2nd cam grooved up the bearings rather nicely with the install. Sounds like your problem may be similar... it's not uncommon.
I'm assuming the installer of the 2nd cam grooved up the bearings rather nicely with the install. Sounds like your problem may be similar... it's not uncommon. 