Help me identify this 20v head

[Berserker]

Friend had this head rebuilt, ports welded and re-machined for a WX application, and we're trying to identify what it came from.

I'm thinking JT or NG, based on the machined hole for the cam-driven vacuum pump rod, but I'm having a hard time figuring out what it is beyond that.

Thoughts?

[DE80q]

It's not an NG, this can be seen by the intake port shape. It's either a JT, or an NF. The NF uses larger intake valves than the JT.

[Berserker]

Based on that I'm assuming JT, since the NF doesn't include the machined port for the vacuum pump rod. You're right about it not being an NG, injectors in the IM on the NG. It's been a long while since I tried to identify any 20v stuff.

Thanks!

[Noisy Cricket]

I have an NG head that is machined for the vacuum pump rod. FYI.

[DE80q]

I believe all the NG heads had vacuum pumps. I'm not sure about the NF heads though, I've never had one in my possession to know.

[Berserker]

Huw Powell's site says there's no vacuum pump on the NF head.

https://audi.humanspeakers.com/nf-vs-ng.htm