Subject: Re: 928 general question: Performance Tips for A/T From: Wally Plumley Date: Wed, 27 Oct 1999 13:05:13 -0400 X-Message-Number: 59 Ralph said - > There seems to be a little handle under the car, near the transmission where you can adjust the firmness of the shifts. < The handle is on the transmission vacuum modulator, which is one of the several devices that adjust the shift quality for different conditions. Get under the car (safely!) and look on the left side of the transmission (driver's side in the USA). You should see a round (about 100 mm dia) drum-shaped object, with a small vacuum hose entering from the top. It should have a black cap in the center. Pull the black cap off. There should be a small bar across the center of the modulator - this is the handle. Pull it straight out. Turning it clockwise will make the shifts later and firmer. Turning it counter-clockwise will make the shifts earlier and softer. Try a turn or two at a time, driving the car for several mile between adjustments, to make sure that you like what happens. Be sure to push the handle back in and put the cap back on. Wally Plumley 928 Specialists -----Original Message----- From: Wally Plumley [mailto:wplumley@bellsouth.net] Sent: Sunday, February 17, 2002 9:41 AM To: 928 Subject: [928] Re: Porsche 928 S4-89 >I have one question for you regarding the automatic gearbox on my Porsche. >The problem is that when I do a Kick-down from stand still the engine never >go over 4700 rpm on the first gear. And for the rest gears it will never go >over 5500 rpm. Is there someting that can be adjusted to go up to the >maximum 6000rpm. (The maximum power is at 6000rpm is't it?). It seems that I >can't get out the maximum of my Porsche at any condition. The first thing to check/adjust is the transmission control pressure cable from the throttle quadrant to the transmission. 1. Make sure that idle speed is correct. 2. Adjust the throttle cable so that there is just barely perceptible play in the cable. 3. Adjust the ball head on the control cable so that it snaps on with no play, but no perceptible movement. If that doesn't help, the primary control for the full throttle shift points is the full throttle control valve. This valve is located on the main valve body, and has an adjustment screw. Turning the screw in lowers the shift speed by about 6 mph per turn. Turning the screw out raises the shift speed by about 6 mph per turn. Your '89 should also have a speed relay that, under ECU control, interrupts the electrical power to the kickdown solenoid at 5900 +/- 60 rpm. This should cause an instant upshift. Of course, if the full throttle control valve causes a shift at an earlier point, the speed relay will never be called upon. Wally Plumley 928 Specialists