380sl has high rpm, car engine very sluggish till after 50 mph
 

Help? I have a 84 380 SL. When stepping on the gas the engine revs to a high rpm, and the engine only goes very slow and sluggishly until I go over 50 mph, then the rpm drops to a normal level? Is this a transmission problem or do I need to replace the computer? or other?;)

I would try changing the fluid/filter in the tranny first. Sounds like transmission issues.

Might start with simply checking the tranny fluid level. Sounds like it might be the better part of a quart low. Continue driving with the fluid low and you'll be looking at a tranny rebuild.

If it is low, then top it up long enough to get a new filter and fluid. Be sure to check the level with the engine/tranny hot (80*C) for proper fluid expansion. You can get a fair read cold - a full tranny, when cold will have the fluid level about 10mm below the bottom mark on the dipstick.