Help with Head Gasket selection

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It's more curiosity than anything. Trying to learn more as I go. I haven't been this deep in a motor in 35 years, and that was the flat head in my Dad's '36 Ford five window coupe. There is definitely something goofy going on with the crank. Never seen rough turning on the face of counterweights like this but I'm not that surprised considering some of the other work that was done to the car. Unless I find something major, the bottom end is going back together the way it came apart. The only thing I can find "wrong" with the heads is the exhaust valve tips sit about .017" lower than the intakes, but the intakes and ex are consistent to each other.
 
OK, if the deck heights are in 1 to 8 order, then yeah.... the pattern seems to be the deck being short in the middle. Is that Starrett straight edge stiff enough? I found localized dips and bumps that cover a wide area and a top-to-bottom slope. You could swap some end to middle piston-rod assemblies and see what happens, but if you really want to know, take one piston-rod assembly and check it in all 8 holes.

BTW, I have seen similar grooving on the throws of a straight-out-of-the-original-engine crank; never thought it was anything but factory machining....??? Never checked how deep it was.

And FWIW I have .020" tip difference between intakes and exhausts on my last Opel head. That came about because I asked the machine shop to set the new bigger valves in the heads to where they were just enough in the heads to have proper seat angles, but not any deeper so as to not have any added obstruction to low lift flow. So that is where the valves ended up. I just accepted the difference and shimmed the valves close. (But it is not a high lift situation either.)
 
The straight edge is straight. I checked it on one of my granite flats and use it on edge so it won't bend. I will verify with my scraped in parallel. it is so straight/flat that if you try to lift it straight up off the granite, it won't come because it is pulling a vacuum. If the deck is that bowed, I have bigger things to fix, so I hope it is the rods. Think I'll leave the crank in but pull the rods and pistons. I just need to know for peace of mind. I think I can check if the throws are even with the rods out too. I might as well, it only costs time.
 
Regarding the copper rods.

Last night I was on another forum and the thread went in the direction of copper colors on roller cam cores and the light bulb went on!

The copper is applied before heat treat then goes thru a chemical bath to remove the copper. They aren't really played just dipped in a copper solution to protect the surface from damage during the procedure.

I used to haul lots of GM engine parts to a heat treat facility in Lansing, MI and I saw some parts go thru with that copper hue.

Likely someone can research this but it's been discussed here a few years ago back when I was assembling parts for my engine deal.

BTW...that heat treat shop did the work for Lunatis crankshafts. I'd see a couple hundred cranks go into the oven everytime I was there. A free extra crank may have altered my Mopar alliance....

Just kidding.
 
Thanks Krooser. You made me look around a bit and I found a patent application where this use of copper coating was described for rods. It says that copper coating is used to prevent the hardening process from reaching certain areas of the rod, by blocking the absorptionof carbon atoms used in the hardening carburizing atmosphere; the coating is applied and then is machined off in the areas where they DO want the hardening process to reach (like inside the big end).

So that makes some sense for the roller cam as you noted: Using the copper to prevent the surface hardening in some areas.

US8074355B1 - Method for manufacturing a connecting rod for an engine - Google Patents
 
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