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
Jonsered Chainsaws, Page 56
Oregon 72EXJ091G PowerCut 3/8 Skiptooth Saw Chain, 050 Gauge, 28 Inches, Silver : Oregon: Patio, Lawn & Garden
Sledrat's Greasey Lil Chainsaw thread, Page 28
Clone 070 Arborist, Chainsaw & Tree Work Forum
2101xp/ top all time muscle saws!!!!!!!!!!!, Page 34
Huztl FarmerTec 070 Build Thread with upgrade info and completed saw, Page 30
Jonsered Chainsaws, Page 56
Arborist Chainsaws
Sledrat's Greasey Lil Chainsaw thread, Page 28