As an owner of both a 617 and a NA 606, I can tell you that the 606 does not have as much torque down at the lower RPM’s. BUT if you spin it up, it acts more like a gasser & dives for 5000 RPM’s making more & more power as it goes (unlike the 617 that runs out of steam at higher RPM’s).

If you are on an acceleration run with the 606, it’s great – smooth as silk and plenty of power. Where I notice the biggest difference is when poking around in slow freeway traffic – if you get caught at low RPM’s there isn’t a whole lot of torque to pull you up to the traffic that’s pulling away… But if you downshift & rev (either kickdown or manually) it scoots right along. I love this car. And I still love the old ’84 as well, but it’s really apples to oranges.

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Current rolling stock:
2001 E55 183,000+ Newest member of the fleet.
2002 E320 83,000 - The "cream-puff"!
1992 500E 217,000+
1995 E300D 412,000+
1998 E300D 155,000+
2001 E320 227,000+
2001 E320 Wagon, 177,000+

Prior MBZ’s:
1952 220 Cab A
1966 300SE
1971 280SE
1973 350SLC (euro)
1980 450SLC
1980 450SLC (#2)
1978 450SLC 5.0
1984 300D ~243,000 & fondly remembered
1993 500E - sorely missed.
1975 VW Scirocco w/ slightly de-tuned Super-Vee engine - Sold after 30+ years.