Some cars actually had a vac advance and vac retard, my 84 bmw did. I think the mbs were set up differently though, as noted above.

The bmw would never run properly with correct power til I modified the distributor to give pre emission controls performance.

Tom W

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[SIGPIC] Diesel loving autocrossing grandpa Architect. 08 Dodge 3/4 ton with Cummins & six speed; I have had about 35 benzes. I have a 39 Studebaker Coupe Express pickup in which I have had installed a 617 turbo and a five speed manual.[SIGPIC]

..I also have a 427 Cobra replica with an aluminum chassis.