Now I know paper figures are by no means everything, but I have been looking at them none the less. It seems to be, the 070 has significantly more torque than the 076, and the same as an 088 (well, 0.1Nm less), while the 090 is quite a bit higher. My sources are the test reports in the reference
070-088-076-090 torque comparisons
070-088-076-090 torque comparisons