Does anyone know if an Engine from a 1982 Mercedes 380 SEL will interchange with a 1988 420 SEL and if the wiring harness will fit? Thanks for all answers in advance!

You're wanting to replace a 420 with a 380? Its not a wise decision... especially if its a US spec 380 engine you're putting in. The 380 US spec was probably the worst mercedes v8. Not only did it have very little power, if its an early 380.. it had a single row timing chain that would snap. A 420 engine should be as easy to find and not cost any different than a 380. They are however both m116 engines and should swap right in... but not a good idea. Just my 2 cents.

I gather from the title that you want to put a 420 in a 380SE? The 420 injection has more bells and whistles than the 380, so the harnesses are not the same. You could try putting the 380 injection on the 420 - that might work but I have never heard of anyone doing it.

__________________
Chuck Taylor
Falls Church VA
'66 200, '66 230SL, '96 SL500. Sold: '81 380SL, '86 300E, '72 250C, '95 C220, 3 '84 280SL's '90 420SEL, '72 280SE, '73 280C, '78 280SE, '70 280SL, '77 450SL, '85 380SL, '87 560SL, '85 380SL, '72 350SL, '96 S500 Coupe