Thanks to Carl Payne

The main differences to the "new" 5.2l and the "old" 318 are in the block and heads. The new block affords roller lifters, yes it has changed lifter agle for same, and has bosses for the lifter retainers. The heads are high-swirl / high-flow heads, though not the old "X" heads of the 340, and obviously the Magnum has that cool intake. the "new" 5.2l came about in changes made in '87, which were fully incorporated by '90. The changes were made to facilitate a more common creation of the 5.9, 5.2, and 3.9 V6 engines.

Webmaster note: with the Magnums came more standardized parts between the 318 and the 360, mainly to the benefit of the 318. The 360 has seen new life in a special edition Jeep Grand Cherokee and the new Durango. The "Next Generation" V8 family produces similar power with less weight, fuel use, and emissions, though durability is unknown. I'll miss the LA family's low-end grunt and long life, but the new engines seem to rev more freely, are more efficient, and may be as bulletproof.
Gary Howell wrote: "The Magnum 318 and 360 engines are LA engines with different cylinder heads. The blocks are physically the same as the earlier LA engines, except the oil passage for the shaft mounted rockers is not drilled, because the Magnum engines oil through the push rods. The boss is there if you need to use the old style heads."