How much does a Slant 6 engine weigh?

http://www.allpar.com/slant6.html ----info off the net ---

Depends upon the accessories. Power steering? AC? Cast iron intake? Cast iron exhaust? Manual trans flywheel and if so the big truck one or the standard one? It also depends upon the year of the engine. Very early ones had a heavier crank. Late cast crank engines are lighter than the common forged crank engines.

published figures show the 6 at 475 and the 273/340 at 525. they show the 360 at 550. Must be something with the block, doubt the crank is that much heavier, virtually identical except for stroke and main diameter.