Hardened Seats

[FirstEliminator]

   Hi,

   Is it possible to put hardened seats of a 1.755 od to accommodate CJ valves in to C1AE or C4AE. The C1AE exhaust seats on one side are like a thin shelf sticking out with nothing underneath. Plus, it looks really close to the water jacket. The C4AE look better, but still of the same design. Even the C8OE is like a shelf too.

  I've been practicing on a junk C7AE head and it looks different. There is a lot of material supporting that side of the exhaust seat where it's a thin shelf on the others. At least on the end cylinders, it has ribs in the water jacket around where the exhaust port are.

  The plan was to use the C1AE heads on my 482. But, I am not confident in sufficient support for a hardened exhaust seat for a CJ valve.  Has anyone just put them I n anyway and had no trouble? The seats I am using are .218 tall.  I took a rough measurement of the C1AE "thin shelf" and it's about .210. This would mean part of the seat would have no support. Not just and edge sticking out, but a section of ring would be floating.

     What is possible?


   thanks,
      Mark

   

[Heo]

Yes i saw that on my heads, And decided to not put seat in them,
Atleast not before the stock seats was worn out and with the
driving i am doing they will last for years i hope

[FirstEliminator]

    I decided to cut the seat pockets in one of the C1AE heads tonight. At .200 depth, it's like paper on the thin shelf side. There is ever so slight of a gusset in the casting below it. It will probably work, but it doesn't seem optimal. I don't have a good means of measuring the wall thickness, but it seems the 1.755 seat ring doesn't cut too far into the surrounding wall where it may intersect the water jacket. Perhaps the best idea would be to cement these in place.

   Mark

[FirstEliminator]

   Here are some pics of the C1AE head.   








   Are we comfortable with a seat ring sitting on this very thin area?   Much risk of failure?








    At first thought, the diameter pocket for the seat ring would have created an area too thin next to the water jacket.   It doesn't appear to be a problem as the pocket for the seat ring doesn't extend into the side very much.


   Mark

[Heo]

Thats why i dont put hardened seats in my C4 heads when i did them
I figured with the low miles i going to drive it they will last for many years
better than risking a major grenading
But i know there is those out there that runned them with seats pressed in
like that with out problems for years

[cjshaker]

Back 23 years ago, when I did the C4 heads for the 390 in my Highboy (engine came out of a '64 Mercury Marauder), I ran into the same problem. I wanted hardened seats because it was a truck and I knew I'd be pulling some heavy loads and some long distances. I ran those heads for a full 22 years, hard, day in and day out and never had a problem. BUT, I had an experienced FE guy that did the work. He was an old timer and he felt that it would be alright. I admit that I didn't have the confidence that he had, but he was right and I was wrong. I still have those heads and am planning on using them again in my 445 stroker for my F350 that I use to pull my car trailer. After all the abuse that I put them through, I think they'll be ok for me to use after I have them touched up on the valve seats.