Based on the baseline dyno charts posted elsewhere in this forum, it's clear to see that the M112 engine has a beautifully linear torque curve which drops off at 4750rpm. What this means is that the engine basically puts out about 10hp in the last 1250 rpm of revs.

If I take a straight edge and make the torque curve flat to 6000rpm, the engine's projected horsepower should be about 40hp more than stock, putting the car at around 260hp instead of 219hp.

So my question is, why does the torque fall off at high rpms, given that the M112 has a fancy dual-length intake manifold? Is it the limitation of the SOHC, 18-valve design? Cam profiles?

I'm a turbo guy, not an all-motor guy. Anyone have any ideas?

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