Batman 357

Trying to match RPM and gears is a problem for me. Sometimes warm idle is 1k & sometimes it’s 1400+. I tried just launching the car in 1st then shifting right away. I do the 1 - 2 shift at about 6 MPH. It shifts smoothly & after that things are pretty much normal. Maybe Santa will bring a transmission rebuild next year….

JRRSA

When I had my 86 with the 915 being smooth was the key. I never shifted to the next gear below 4,500 RPM and when I did shift I hesitated halfway through, blipped the throttle and it fell nicely into the next gear. Downshifting was same type of deal. This activity was what made the 915 fun to drive. There was nothing like hitting a redline upshift or downshift just right with a perfect rev match.

Brads911sc

I changed my Trans oil today. Put in Swepco 201. Seems to shift smoother now...

Amber Gramps

check your option codes for 220 as the LSD acts much different with the correct additive.

srf506

Yeah, its important to run Swepco or the equivalent in these old boxes. It seems they need that little bit of friction that you gain from running syns especially. You also really can't rush these boxes. It a definite 1 and a 2 shift rhythm. Blipping the throttle or double clutching is really helpful, especially downshifting the car. Of course as the mileage goes up the clutch, synchros, and shift linkage seems to take a beating and wear causing more issues.

ne ohio 911

I installed Swepco 201, a RennShift shifter and Wevo Coupler. Wonderful improvements to the shifting on the 915. My syncros were replaced a few years back. Unfortunately, I don't think any of these upgrades will help if your syncros are in bad shape.