Head gaskets,steel shim or composite-crushed thickness???

[wsa111]

There are many choices of head gaskets for these engines.
Fel-pro composite .052 crushed thickness.
victor .045 crushed thickness.
ford composite C9DE6051C which is the steel shim replacement available in 1969. What is the compressed thickness of this gasket. I have heard it is about .028 compressed??? Can anyone verify this??
There is also a felpro steel shim gasket #7916 which is .021 compressed.
This post is more of a question rather than info.
Need a second or other opinions on the correctness of the above specifications.
I need to make a decision on which gasket i will use.
The above head gaskets will bring my compression from a high of 9.8 to as low as 8.5 depending which headgasket i use.
I have all these gaskets at my disposal. Advise on the correctness of the above. Any & all comments would be appreciated. Willaim

 

[CZLN6]

Howdy William:

The FoMoCo replacement composite gasket C9DE 6051 C, is listed at .037" thickness. I have not seen a compressed thickness dimension.

FYI- all gaskets compress more as torque specs go up. This is more true for composite gaskets. They do seal better too.

The Fel Pro #7916 PT-1 is their composite type gasket. I've measured new ones at .055" and 2 used, compressed at .046".

Opinion- If I were you I'd start by decking the block to zero, use a small dished piston, a NAPA composite Victor #3910, new .046" compressed .044", and mill the head to achieve my desired CR.

If you are only doing a head mod, then mill to compensate for the difference in compressed thicknesses.

A deck clearance of .044" is still too much for ideal quench, but the trade off is much better sealing, and the rarity of the FoMoCo composite and the steel shim gaskets. If you can find a FoMoCo composite that would be the best of both worlds.

Adios, David