How about rebuilding your engine into a 2.1L with 12:1 compression and 88mm diesel crank. Install some aggressive cams and rev all the way to 9000 RPM with solid lifters and bigger valves etc. I am sure you will easily hit 200-250HP or more.
not worth it.
you could m52/s52 swap your car for less than that, and god knows how much power you could pull from one of those motors to make the cost equivilent...cams, obd1 manifold, intake, exhaust, with a nice chip thats 250hp on the wheels.
24v swap ftw if you want some REAL power
to reitterate in more simple terms, m42 is a great DD motor, a little peppy up top, but it's not a "powerful motor".. your not going to see a big jump in power unless you drop some serious $, or you boost the shit..ALOT.
