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Discussion Starter · #1 ·
Been building plenty of motors and read alot, then take my time and pay attention to detail , measure right etc etc when putting it together but never have played with a big block chevy

Few questions, I list them along with a picture. When I first picked this block up I was barely out of a wheelchair and drove 100 miles to get it, in the rain so at first glance I figured the cam journal had been machined for a roller timing set, like some small block fords I have done (Daves engine machined the thrust plates for me on all of them) so I forked over the low dough for it (150 with new standard bore flat tops and arp mains studs)

Anyway, the pistons are junk, to me because they have all witness marks from being bitch slapped by valves and last time I ran a motor with pistons after them having been bitch slapped by valves and not replacing the pistons the damn thing came apart getting on the on ramp, learned my lesson they probably had a crack at the wrist pin area after lookin at the carnage. Broke my dart heads and hurt my butt and man that was 15 years ago.

Anyway BESIDES needing the obvious cam bearings:

1. Is this block junk?



2. If not what causes this?



3. How do I remedy it, if the block isnt a boat anchor now?



4. Would the motor supposedly having a solid roller in it have anything to do with this? (I'm guessin, yes)



Thanks, in advance.

Dan
 

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Dan,
Thats not all that unusual for a big block, I have seen a few that way. What you need to do is have the front of the block machined so that you can install either a bronze shim or a roller bearing. It is best to do it in a Bridgeport mill so you can get it straight.

As far as the roller cam causing it, I would say no unless somebody had the cam button way too tight and it was forcing the cam to the back of the block. Actually roller cams are less likely to do this because the lobes do not tend to pull the cam towards the back of the block, that is why you need a cam button with them.
 

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Discussion Starter · #3 ·
Dan,
Thats not all that unusual for a big block, I have seen a few that way. What you need to do is have the front of the block machined so that you can install either a bronze shim or a roller bearing. It is best to do it in a Bridgeport mill so you can get it straight.

As far as the roller cam causing it, I would say no unless somebody had the cam button way too tight and it was forcing the cam to the back of the block. Actually roller cams are less likely to do this because the lobes do not tend to pull the cam towards the back of the block, that is why you need a cam button with them.
Thanks for the input, Bill. Any idea of how much they usually take off?
 

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66 El Camino 57 Chevy pickup 2004 Tahoe
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there's shims available in various thicknesses, machinist should make the call after seeing how much has to be taken off to clean. BTW, unecessary and un-needed HV oil pumps contribute to this.
 

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66 El Camino 57 Chevy pickup 2004 Tahoe
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BTW, the front cam bearing still has to be installed with the oil holes over the groove.
 
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