Due to lack of compression I have removed both my heads to bring into the machine shop. As I was cleaning them I noticed a few minor casting details. I checked the part number on both heads and this is what I came up with.

021-101-371-S (1.8 Bus) Passenger side
022-101-372-G (2.0 Bus) Drivers side

The guy I bought this "rebuilt" engine from must have mixed and matched a few components. When I get these heads re-surfaced, do you think the CC's will be close? Ive never built an engine like this before.

I dont know how that is even possible.
I thought (about to get 'lerned') that you could not mix 1.8L & 2.0L because they are always 3 vs 4 bolt patterns on the intake side.
I am probably wrong when it comes to bus parts though.

+1 ... 'bus' 2.0 heads have 4 bolts on the intake as well ... but I believe the chambers and possibly also valve sizes are different from each other....

They both have 4 intake studs. I will have to get a caliper and measure both valves to double check that. If that's the case this rebuild might be a little more expensive than I was thinking.

Stock configuration:

021 101 371S ... 39.3mm Intake X 34mm Exhaust. FI head ('74 1.8L)

022 101 372G ... 37.5mm Intake X 33mm Exhaust. FI head ('76-'78 2.0L)

Combustion chambers have a slightly different shape between the two.

Interchangeable. "G" heads could have had the valves upped in size when rebuilt.

I did remove the valves to clean and noticed that one head had vintage looking valve with the VW logo on them and the other head looked like more modern valves. Would it be frowned upon to use 2 differently shaped chambers? This rebuild is turning into a disaster. The sad part about all of this is that the car came with a blown 2.0L engine. And I have this guy the core. As I've learned more about these engines I realize that was a huge mistake.

Don't give up, this will be worth it in the end.

See if you can pick up a set of rebuilt 1.8l heads as they are much better flowing than the 2.0l bus and 1.7l 914 heads, plus you will not need to get new intake manifolds (for the proper 2.0l intake bolt config) nor new tin (to move the spark plug to the 2.0l lower location).

Don't let this drag you down, but given the possibility of mixing and matching lots of parts on these cars, a few unscrupulous or clueless people will have done whatever it took to get it running/sold/etc.

Luckily I still have both style tin and intake manifolds for the 2.0. I will try searching for a set of matching rebuilt heads. No point in spending the money rebuilding 2 oddball bus heads... FML

YEs,

Go find a matching pair and do it right.

I would take a close look at the rest of the rotating assembly too. Mix of rods, pistons and cylinders. I had a motor with 6mm rockers on one side and 8mm on the other.

Just ordered a matching pair of 1.8 heads on here. How do you measure the rockers? Hope its legit.

I am packing them right now.