Hi AMCO72,
Engine wise in Sports Sedans they could have been anything from 1293 - almost 1600cc, standard modified internals to the most extravagent available at the time. In iron headed form to 8 Port Crossflow as Steve said above. 3 or 4 syncro SCCR gearsets although some now are running dog boxes, and preference would be a LSD.
HP will obviously vary from I guess 100 - 170ish depending on who you talk to, whose dyno etc etc. at the engine.
But saying that, Torque is I think very important in a Mini engine, unless of course you like to wring its neck.
Now I believe a little birdy I was talking to recently was telling me about a Crossflow engine with 120lbft of torque as this engine may belong to yourself? The figures I was told I think would make this a dynamite car to drive, very tractable and fast.
Probably rambling a bit.
Thanks
Ian