I Might Have Found Something Pretty Cool.....
Ok here it bees. @Charrlie_S, I took the thickness measurement you asked for. I have not CC'd it yet, as it's pretty cold here tonight, so I'll do that tomorrow. I measured first, an unmilled open chamber "revised" chamber head and it's thickness from the valve cover rail to the deck is 3.614". The closed chamber head in the same place measures 3.625", so it is actually a little thicker. So, I would assume the closed chamber has never been milled. Certainly not milled from open to closed, which will be evident in the next pictures.
First, the casting number. That 2nd "4" is a 4, it's just a bad angle and the flash helped wash it out. Maybe that's a date code above it, I don't know.
Next, here is a really good chamber closeup. Very evidently an as cast closed chamber.
Here, I show the locator hole for the dowel pin. The as cast factory chamfer around the hole. No milling. Not even evidence of a broach or rock cut.
Here is a comparison between the chamber "smiles". I thought at first the closed chamber smile was a little smaller, but looking closer, I believe it's the same. I'll let yall decide.
And the closed chamber "smile".
That's it for now. I think beyond a shadow of a doubt, the head is as cast from the factory. I'll have some chamber numbers tomorrow when it's a little warmer out.
Rob
Ok here it bees. @Charrlie_S, I took the thickness measurement you asked for. I have not CC'd it yet, as it's pretty cold here tonight, so I'll do that tomorrow. I measured first, an unmilled open chamber "revised" chamber head and it's thickness from the valve cover rail to the deck is 3.614". The closed chamber head in the same place measures 3.625", so it is actually a little thicker. So, I would assume the closed chamber has never been milled. Certainly not milled from open to closed, which will be evident in the next pictures.
First, the casting number. That 2nd "4" is a 4, it's just a bad angle and the flash helped wash it out. Maybe that's a date code above it, I don't know.
Next, here is a really good chamber closeup. Very evidently an as cast closed chamber.
Here, I show the locator hole for the dowel pin. The as cast factory chamfer around the hole. No milling. Not even evidence of a broach or rock cut.
Here is a comparison between the chamber "smiles". I thought at first the closed chamber smile was a little smaller, but looking closer, I believe it's the same. I'll let yall decide.
And the closed chamber "smile".
That's it for now. I think beyond a shadow of a doubt, the head is as cast from the factory. I'll have some chamber numbers tomorrow when it's a little warmer out.
Rob
