401 heads have double gaskets

[iCEMAN]

Any idea why the PO of my Jeep would double stack the head gaskets? Guy who is taking it apart for me thinks it may be due to the heads being warped. Sound right?

Not sure how they would know when putting it together that they were not flat, but looking for thoughts/suggestions.

 

[IOPort51]

Any idea why the PO of my Jeep would double stack the head gaskets? Guy who is taking it apart for me thinks it may be due to the heads being warped. Sound right?

Not sure how they would know when putting it together that they were not flat, but looking for thoughts/suggestions.

Does the 401 say 401 on the side? I know this is a dumb question but I am thinking that if you double stack the gasket on a AMC 304 you could , maybe , put 360 or 401 heads on it and clear the valves?
would this lower compression significantly? so it would run regular gas.
Put a straight edge on the head surface and see if you can slide a feeler gauge under it. A three foot section of precision ground cold rolled steel from a bearing supply works well for this and is not too expensive.

 

[iCEMAN]

Didn't think of the PO putting different heads on it and calling it a 401, will have to look.

I know it has the roller rocker setup in there, so that may be why the extra gasket.

 

[Old Dog]

Maybe they shaved the head once before and thought this would bring the compression and valve clearance back to stock.

 

[LongHorn]

Any idea why the PO of my Jeep would double stack the head gaskets? Guy who is taking it apart for me thinks it may be due to the heads being warped. Sound right?

Not sure how they would know when putting it together that they were not flat, but looking for thoughts/suggestions.

My 401 came out of a early 71' AMX & had 10.25 to compression.
I've heard of people using double head gaskets to reduce to the compression.
They said it would come down just under 10 to 1. I know back in the day we used thin steel shim head gaskets the raise the compression.

 

[iCEMAN]

Well, continuing to work on the 401 now that I have some free time again. Picked up a new set of heads to rebuild as the old ones had a crack in them.

When we took the valves out of the old heads, discovered two valves had no guides on them. Gone. No indication there were ever any on there. Any one ever seen this before?