[donut]

Couldn't remember exactly how the lock-up worked (only turbo350c I've had was in the mid '90's) But everybody was looking at the engine and missing the elephant in the room.

You mentioned the different curves and got me thinking. If mine was acting like the OP's, drop a gear and go. I had similar issues with an engine when I lost 2nd gear in a 3 speed.

Didn't even consider the air temp. Usually when it got cold enough to need gloves, the tools got put away. Course I have been down south for a couple years now...