Hmmm... my old worked car was certainly quicker off the mark than the SiR, it pulled 100 in 7 seconds, only marginally faster, but I was running a city turbo gearbox which has top end and torque ratios in it compared to the EB 4 speed. Then again, I had as much torque as the SiR as I recollect, the engine was massively out of proportion. 73mm bore compared to an 82mm stroke (EN1 crank and rods). Factory 1224s were 72mm bore and 76mm stroke (geez, I hope I got that right off the top of my head). EB1s were 70x 76 as an 1170cc motor.
The only issue was that I blew the mugen headgasket twice at 7500 rpm and cracked the head once when I shaved it too much. You don't have that sort of an issue with a SiR.
I'll dig out some mugen/bassini (jackson racing)/dell orto pics later. I think I have a whole ton of them somewhere but only a very few of my car
