Thanks to the Isuzu G-series Twin Cam forums and Poida for fixing the link, mirrored here for preservation.

http://bellett.net/files/G200WE%20Engin ... ese%29.pdf

is anyone able to find the specs for torquing the head and able to translate to english?

2-16 (scanned page 22) looks like it.

The diagram shows 10 kg-m. The text in the paragraph above that reads 8 kg-m.
Without deciphering, I am going to guess torque to 8 kg-m, then torque again to 10 kg-m.

The G200Z manual says torque to 6.0 kg-m and then torque again to 10.0 kg-m.

Awesome, thanks for that!

Kilograms meters (Kg m) × 9.804 = Newton meters (Nm)

so 78.432 Nm then 98.04 Nm

Ive got my head at the engine builders now, and he was looking for the valve clearances. Due to time, he went with a best guess, but JT191, can you find those and post them up for the record? TIA!

Scanned page 2-4. PDF page 16.
About halfway down on the right side of the left page.
The little chart says Valve Clearances. Top line says Inlet: .13. Bottom line says Exhaust .23.

The G200Z manual shows intake .15 mm and exhaust .25 mm. So the unit in the Japanese manual would be mm. And they are a little tighter than the SOHC (which is rocker style instead of shim on bucket).

The chart on the facing page in the G200W manual shows all the part numbers for the range of shim thicknesses. That's a wider range than the 4XE1 engine.

Thanks!