Cylinder Heads

Does AH21 stamped on my cylinder head mean anything to anyone?

Oh yes! It is one more than the AH - 20 model. Other than that, absolutely nothing.

Hope that helps...

I think that is just a casting number - perhaps it shows production date or the batch of alloy used - so of no real value. There should be model numbers like 111 103 976 or 022 101 352. These are more useful as they can be traced to the year, original dispacement and model VW engine they were used on. One of the VW rebuilding books has a table that decodes some of the info. Years ago I took 2 heads off and engine in for a valve grind and discovered simply by the head part number that one was for a T1 and the other a Type 3 - one had a step in the head area and the other didn't. One had a step cut in head area and other did not. You might see 041, 043 or 044 as part of the head number - it can tie back to id the valve size. You can bet that 022 heads (from a heavy, boxy bus) lived a tougher life than say 111 heads from a lighter bug. I'll see if the book has a decent cross reference table in it.