[W126 Coupe] Engine replacement?

[Richard Hesek]

Barry,
  When I replaced my 560SEC engine in '05 I was told by everybody involved
that I need an engine from a coupe.
 The engine supplier, my mechanic and others.
  There may be specific reasons in the 1987 560 vintage that do not apply
to the 380 but I am not aware of any.
  Is your 380 engine a single row timing chain? And what year is it?

Rick Hesek
New England

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Hi guys, Can I simply exchange a 420 ,500 or 560 engine to my
380SEC? Any extra requirements? Can the engine be from a sedan or does
it have to be from another coupe? Or if this is too big an issue can you
suggest any way to pep up my 380? All I have done so far is modify
exhaust. It has done around 150,000 miles and runs smoothy.Could do with
some extra mid range grunt and that slow change from 2nd to 3rd is
apparently "normal"?.......I want a manual gearbox!....Barry (Brisbane
AUS)