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Old 02-18-2012, 04:20 PM   #1
savatreatabvr
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BBC Valve Adjustment Question?

When I adjust my mid 70's BBC valve it runs good for a while then goes back to running the way it did before I did the adjustment! I know it means the 454 has high miles and things are a little worn out but what is it that's worn out? The cam, the lifters, what else can it be?
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Old 02-18-2012, 04:38 PM   #2
STOCKISH
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Re: BBC Valve Adjustment Question?

How long does it take to start running bad again? Could be cam, lifters, rocker nuts backing off, etc...
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Old 02-18-2012, 04:47 PM   #3
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Re: BBC Valve Adjustment Question?

It takes 10 miles or so + or -, never thought about how long but I did notice that some of the rocker arm studs show more threads than others, shouldn't they all be about the same?

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How long does it take to start running bad again? Could be cam, lifters, rocker nuts backing off, etc...
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Old 02-18-2012, 04:50 PM   #4
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Re: BBC Valve Adjustment Question?

and some don't seem to make much of a difference in the way it runs while doing the running adjustment procedure!

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It takes 10 miles or so + or -, never thought about how long but I did notice that some of the rocker arm studs show more threads than others, shouldn't they all be about the same?
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Old 02-18-2012, 11:05 PM   #5
STOCKISH
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Re: BBC Valve Adjustment Question?

There should be the same amount of threads showing. Sounds like the press in rocker arm studs are pulling out of the heads. Not all that uncommon. Time to upgrade to screw in studs! Fix it before something more catastrophic happens though.
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Old 02-19-2012, 12:45 AM   #6
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Re: BBC Valve Adjustment Question?

BBC have screw in studs. Its the SBC that have pressed in studs. Sounds like your hydrolic lifters that might be causing your problem.
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Old 02-19-2012, 05:54 PM   #7
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Re: BBC Valve Adjustment Question?

Ooh yeah, that's true too. Well, sounds like the lifters are dying out on ya. All the more reason for a performance cam swap!
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