Poly Engine what was good/bad about it and why is the LA better?

Very similar. Thick wall castings, a little more material in the bellhousing area and maybe the lifter valley. I haven't measured that, but it does look beefier. Doesn't have as many freeze plugs as the LA. Chrysler changed very little to adapt to the LA. It's why the LA still has the 59 degree lifter angle. They are much more of a straight shot to the rockers on the poly.