my firm belief is that there is a harmonic in the engine trans mount configuration that cant be solved by laymen. there's probably a good reason MB never put 4spds in 300 turbos. my guess is the NA need to operate at higher RPM since they do not have the power to even try to push the car at 1800RPM. as long as you are above 2000 RPM there is no vibe.

__________________

1982 300CD Turbo (Otis, "ups & downs") parts for sale
2003 TJ with Hemi (to go anywhere, quickly) sold
2001 Excursion Powerstroke (to go dependably)
1970 Mustang 428SCJ (to go fast)
1962 Corvette LS1 (to go in style)
2001 Schwinn Grape Krate 10spd (if all else fails)

The very heavy 300d flywheel and the extra little mass around the flex joint at the tranny make it very very slight.

The 300 with a 240 fw and no extra mass at the flex vibes more but not enough to make me want an automatic!

__________________
[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.

me too, once you get used to the 3200RPM shift points the car is a blast to drive, heck it will even outrun a lot of the 4 banger ricers. I need to take the car out and do a 0-60 run. I know its pretty good with the gear I have now.

__________________

1982 300CD Turbo (Otis, "ups & downs") parts for sale
2003 TJ with Hemi (to go anywhere, quickly) sold
2001 Excursion Powerstroke (to go dependably)
1970 Mustang 428SCJ (to go fast)
1962 Corvette LS1 (to go in style)
2001 Schwinn Grape Krate 10spd (if all else fails)