E28
The E28 is the third edition of BMW's 5-series. It replaced the E12 in 1981, and was replaced by the E34 in 1988. It is an established and appreciating classic, thanks primarily to its iconic shark-nosed front end which it shares with the E21.
The E28 is particularly famous for being the chassis for the very first M5. By combining the saloon chassis with the engine from the phenomenal M1, BMW were able to produce a 3.5-litre monster with up to 282hp. And with only 2,191 units ever built, the E28 M5 is a very rare and very desirable beast.
Compatible Parts
These are the parts can be bolted directly to the E30 with little or no modification. They are considered an upgrade for either strength, performance or cost reasons. Anything not on this list is either directly incompatible or requires significant fabrication to fit.
Engines
Main article: Engine Swaps
NOTE: The engine mounts for the E28 M5 are desirable for the M50/M52 engine swap.
Radiator
The radiator fitted to the largest M30 engine, the 535i, is considered the best for those contemplating an M50/M52 engine swap.
Differential
Small case differentials were fitted to the E28, but both the back plate and output flanges need to be swapped to E30 equivalents.