I wanna say the block full assembled with pistons/rods/crank is about 200 lbs (gotta love those iron blocks, my brother and I struggled to carry it into my apartment.) The head with cams, gears and cam cover is between 100-150.
the two piece intake manifold is about 40.
around 390-400 for the bulk of it would be my best guess.
no way it weighs that much james. i just built a 305sb for my friend with minimal accessories and just the long block was 350lbs. no way a 1.8 4 cyl with an aluminum head is going to outweigh a small block chevy v8.
ive lifted the assembled heads before right off the engine, i wouldnt have been able to do so if it weighed 100-150lbs, let alone stretched over the front of the car.