Join Date: Nov 2001
Location: state of confusion
From what I understand, the LS engines, aluminum mod motors, and aluminum-headed 289/302 based engines are roughly similar in weight. Since it appears that midrange torque is going to be more useful to you than peak HP, I'd go with some LS variant. Preferably in one of the larger displacements, unless there's a class weight break that you still want to fall on the "right" side of.
Something else to consider is the physical engine dimensions - the 4.6L 3-valve is a pretty bulky lump even if it isn't particularly heavy. I think the 5.0 DOHC I saw at an auto show a while back is even wider.
Over the years, hotrodders have been swapping everything from Chevys to Cadillacs into Fords - and plenty of diehard GM guys wouldn't use anything but a 9" out back. I don't think whatever engine you end up with will care what chassis it's sitting in.
Mine: '08 GT, 5MT, black/light graphite, un-Fstock (DD, occasional track day)
Wife's: '10 Legacy 2.5GT (DD, six-speed manual)
Spare:'01 20AE Maxima, 5MT (also my bad weather alternate)
Various Loose Parts: '79 Malibu
Last edited by Norm Peterson; 11-19-2010 at 01:19 PM.