I have driven mach4’s converted car. Lovely ride.
It is good you are upgrading the motor before the swap.
My 87 560SL is a beast on the road, and I would hate to see one not have the peppy beast I drive.

The 617 turbo has strong pulling power, but not the neck snapping power of the V8.


If you don’t already have the 617, maybe you might look into the 602Turbo for a diesel powerplant?

I think the combination of smaller more modern engine, automatically adjusting valves, and aluminum head could translate into a slightly better ride. Of course,ALL the build tips would be thrown out the window, and require you to start from scratch on it.

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John HAUL AWAY, OR CRUSHED CARS!!! HELP ME keep the cars out of the crusher! A/C Thread
"as I ride with my a/c on... I have fond memories of sweaty oily saturdays and spewing R12 into the air. THANKS for all you do!

My drivers:
1987 190D 2.5Turbo
1987 560SL convertible
1987 190D 2.5-5SPEED!!!

1987 300TD
2005 Dodge Sprinter 2500 158"WB
1994GMC 2500 6.5Turbo truck... I had to put the ladder somewhere!