Upgraded 2.6 liter cylinder head?

Is there a source for the upgraded aftermarket cylinder head for the 1980 D-50 2.6 liter motor?

This is what I did. You just need to find the head. Some place like clear-water heads out of Florida. My head had the large cam plugs.
http://www.mightyram50.net/vbulletin...On-A-G54B-2-6L

I had a 4G52 engine in my first real build. It was a narrow gasket head without the air channel and ports in it and mechanical rocker assemblies. So I'm going to take an uneducated guess that the generation with the channel is the transition engine between the 4G52 and the 4G63 engine (G52B?). It also ran a slightly higher compression ratio (think it was a bit over 9.5-1).

yes the G52B is the almost the same as the 4g52 head, except the 4g52 is a car head and has extra emissions ports that the g52b doesn't have where the head meets the block - see camoit's g52b to g54b head swap sticky.

The change in head volume is listed in the thread. It's so minimal you don't feel any difference.