I posted about a month ago about the readings on my 84 turbo, which were 128, 128, 125, and 128. These are all below the minumum as per the Bently, but posters said that was acceptable for a low compression turbo.
I just tested the compression on the B21ft in this car I picked up for 25 bucks (complete with Virgos and an ambient temp guage) and got 150, 160, 150, 150. I know that is acceptable, but I am still trying to find out what the compression b21ft with almost no wear.
I am probably going to swap engines. The one it the beater purs like a kitten compared to the one in my 84 and it would be a shame to send that engine to the crusher. The car is not restorable. Its rusted out everywhere, and a forklift hit the passenger side.

Hmmm. The Green Book claims that the acceptable range for that motor is 120-160 psi. How many miles on the motor with the lower numbers?

The one with the lower numbers has about 260000 kilometers. When I first got it the wastegate actuator was blown. I have a feeling it was badly overboosted over several years.

The one with the higher compression has higher mileage, at about 285000, but it appears to be well cared for. It had good quality plugs and wires, and many new parts.

Thanks for the Green book info. Thats exatly what I was looking for. I guess thats another mistake in the Bentley Manual. So my higher compression engine is close to the top of the range.