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Old 07-01-2016, 02:43 PM   #1
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Default Found something new I can break.

Intake cam. I think a cam cap broke first.

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Old 07-01-2016, 02:49 PM   #2
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wowza
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Old 07-01-2016, 02:56 PM   #3
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Time for someone to build billet cam cap replacements.
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Old 07-01-2016, 03:00 PM   #4
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Interesting wear on the tops of the lifters. Only appears on #4 lifters. It's like pitting.

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Old 07-01-2016, 03:01 PM   #5
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was the car overrevved?
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Old 07-01-2016, 03:03 PM   #6
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Quote:
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Time for someone to build billet cam cap replacements.
I just bought all new bolts. journals all look good.
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Old 07-01-2016, 03:04 PM   #7
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was the car overrevved?
It broke as the car was pulling through a finish at near the rev limit I have set. 8600 rpm.
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Old 07-01-2016, 03:07 PM   #8
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I have a theory why it broke
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Old 07-01-2016, 03:17 PM   #9
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boop

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I have a hypothesis as to why it broke
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Old 07-01-2016, 08:01 PM   #10
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Im using Carrillo A-beam rods as well. small bolts. probably living dangerously.
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Old 07-01-2016, 08:57 PM   #11
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Cripes Bob. Did you pull the head yet? What do the #4 valves look like?
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Old 07-01-2016, 09:17 PM   #12
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holy ****. 8600rpm?

I can't even imagine the drivetrain vibration and noise at that rpm. It is almost unbearable in my (street) car at 7200rpm.
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Old 07-02-2016, 12:32 AM   #13
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Quote:
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Cripes Bob. Did you pull the head yet? What do the #4 valves look like?
Valves and cam journals and everything look perfect didnt pull it. I put a new cam and cam cap bolts in and it runs great again. The only lifter buckets that showed odd wear were the two on the #4 intake. they are on back order though. They were Supertech shim under bucket lifters quite a bit lighter weight than stock. springs are also Supertech the medium doubles.

the intake valves are also Supertech and I think they are ones made before supertech changed there manufacturing process because I have never expeianced seat wear with them that other people have.

I suspect one of the cam cap bolts on the back cam journal broke first and with the end of the cam not being suported it had some bending moment and the reverse bending cycles eventually killed it.
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Old 07-02-2016, 01:31 PM   #14
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I hope this never happens to me with my unobtanium cams...
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