La 318 engine advice

[DirkRhodie]

So their response was that they only lightly skimmed both decks......but as one can see on my assembly the left bank of pistons are all definitely " out the hole" as per my uploaded pics.
They say it can be remedied by skimming both sides of the connecting rods big ends and re honing/cutting to fit the bearing shell's.......now to me that's complete stupidly and even if it did work it would mean a total rebalance of the rotating assembly.

No mention of who covers the costs....
The most annoying thing is I have used the same shop a few times on other projects and their work has always been tops.
I have in turn spoken to a V8 specialist in Johannesburg and he says I must work out my clearances and calculate the correct gasket size for bothe banks and order from Cometic as they do have gaskets of various thickness.
As long as my compression ratio is correct on both banks then I shouldn't have any issues....

 

[Big_John]

So their response was that they only lightly skimmed both decks......but as one can see on my assembly the left bank of pistons are all definitely " out the hole" as per my uploaded pics.

Since the piston is supposed to have .010" positive deck height, why not just have them cut the other side to match? That extra .003" isn't going to matter.

 

[Toolmanmike]

Good day Gents,
Please assist me in finding a solution to my issue. So I'm rebuilding a 1967 la 318 engine with kb167 pistons, now the issue that's developed due to the machine shop decking the block before I actually gave them the pistons in order toas determine the amount they can deck it too.
Long story short is now on assembly the left/passenger side of the block the pistons are protruding by 0.013 while the right side is flush.
Now the issue is this engine is an early 67 so it has the "66" 273 closed chamber heads so I can't skim the one head slightly less to correct compression.
I do believe one can use different thickness head gaskets to compensate, problem is I'm in South Africa so getting two different thickness head gaskets from a supplier can be an issue as I haven't got any contacts that can assist other that just buying on line and hoping I get the correct gaskets.

Can anyone assist, l'm loading some pics please bear in mind that the dial indicator is in millimetres.
Also loo at the damage the done to the cam bearings which were brand new Clevite Malhe.

Make ones blood boil.

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Pull the pistons and have them mill the tops .013. I would rather do that than deal with clearance issues on that side. A thicker head gasket would make it work. Not fix it proper but make it work.

 

[CBODY67]

I have heard of "skimming" as to connecting rod CAPS, but not the main part of the rod. From back in the day of the poured babbitt bearing Chevy inline 6cyl engines. To account for bearing wear. "Select fit" of sorts.

As to "piston weight", there is a range of values for piston weights. Which is why there is a "balance pad" on the pin boss of the piston's underside. The uncut pistons could be brought down to close to what the machined pistons turn out to be. Just have to see what is needed and can be done in that respect.

NOW . . . how did they cut the block? Was it on a machine that uses dials and adjustment wheels to get to the same number on each side OR a "rotating rock" that cuts as the block is slid over the table (with the rotating rock in the middle)? In the rotating rock situation, the rock is a measured amount above the sliding surface, such that if the block is slid at a constant speed, only a little metal is ground off. BUT if not done correctly, the block can be ruined. In this scenario, it relies upon the basic factory OEM machining to be pretty much correct, but no way to accurately measure the real amount of metal removed.

For general rebuilds, the rotating rock has worked well for decades, before the "fancier" lathe cutters became less expensive.

Usually, the type of cutter can be determined by the pattern left on the top of the deck. I'm now suspecting it was a rotating rock. Which ALSO can mean the different thickness of head gaskets might be the best solution, all things considered. I'm suspecting the difference in compression ratio might be similar to what happens after the cyl bores get some wear on them and the rings get a bit worn.

The other thing is that if the decks were not the same height, using the rotating rock, that's how the decks were when Chrysler originally built that engine. So the resultant smoothness should not change much, if at all?

Whatever y'all work out. Your money and such.

CBODY67