Sportomatic (69 911T) slips until high RPM

[tgittens]

Hi,
Just got my 69 911T Sportomatic back from the mechanic. It went in for transmission work but came out with rebuilt Carbs and replaced gaskets and seals (valve cover and timing cover and crank seal) and transmission still not working correctly.

The mechanic said he checked the vacuum and it was fine. Replaced clutch pressure plate, shift rod bushing, clutch disc, hot air hoses. Even had the torque converter rebuilt by an outside shop. The mechanic suspects the torque converter still because the car only engages gears at high rpm and stalls out at stop in gear.

questions: Could this still be a vacuum issue (diaphragm) even though he checked or could it be a torque converter issue even though the outside shop said they rebuilt it?

Any suggestions? Next step is converting to manual since I've had the car since 2009 and yet to have a satisfying drive.

thanks!

[Matt at Pelican Parts]

It certainly sounds related to the clutch/ engagement system. Is it safe to say all the parts installed have been confirmed as fitting that year? I know certain models had different disc thicknesses.

Check out these older threads about a similar issue. They might help:
https://forums.pelicanparts.com/porsche-911-technical-forum/1099056-sportomatic-clutch-slipping.html
https://forums.pelicanparts.com/porsche-911-technical-forum/562567-1971-sportomatic-repair.html

[tgittens]

Yes the car is all original parts and the replaced clutch disc is 90111601400 which is correct for that year. The mechanic is reputable Porsche mechanic but doesn't have access to a good torque converter shop or part.