Originally Posted by cRiPpLe_rOoStEr
Unless you turbocharge it
The Iron Duke was never intended to be more than a large compact economy engine. You could boost it, but don't expect the ride to last long. I don't think a stock Duke is good for more than 120-140 horsepower.
Back in the day Pontiac made available a so-called Super Duty Four block, which duplicated Duke geometry but in much heavier hardware. Other geometries were shared with other Pontiac Super Duty engines, so there could be some entertaining shopping done at the Pontiac parts counter. Done right you could build a Duke stroker past 200 cubes, 300 horsepower and one hell of a shock to anybody lifting the hood after you smoked him at the lights. It looks like a Duke but goes like stink.
You can still get an SD4 engine from Kansas Racing Products. Crack the wallet wiiiide open, they ain't cheap.
NOTE: I apologize handsomely for stepping way far away from the ecomodder paradigm. I just like the Duke, and I lurves