Adjusted the ALDA last night, it shifts soooo much smoother now.

To keep a long story short, it has been soft in the pedal until the boost kicks it around 2000rpm or so. Starting off slowly would give me a real kick in the seat 1-2 shift, and the 2-3 & 3-4 were a bit harsh also. In the rain the 1-2 shift would sometimes get me sideways, kind of embarrasing.

I checked the vacuum, no leaks no problems. Shifts fine above 1/2 throttle, except for the 1-2. I've changed ATF twice this year, hoping that synthetic would help, no change.

I have resisted turning the ALDA because I was afraid more power would be more thump, and I'd like to keep the transmission together. I also wanted to keep the car as original and stock as possible, it has lasted this long in near-perfect original condition and all, ...

I have considered adjusting the Bowden cable for short-shifts to keep the shifting out of the boost power, and adjusting the vacuum modulator to soften the shifts. The bowden-cable change would mess up my downshift, the modulator adjustment could cause flaring at higher throttle settings, plus it was currently adjusted correctly so these seemed more like "band-aids".

So finally, I decided to adjust the ALDA just to see if I can recover some part-throttle acceleration and reduce the 2000rpm afterburner effect, not knowing it would solve two problems at once.

Not enough room to swing wrenches on mine (602 turbo / 201 body). Using a couple of large-sharp screwdrivers I was able to pick away at the cover until it came off. Loosening the 10mm lock-nut was easy, ... but then what a *****. Fortunately after about 1/4 turn, I was able to turn the adjustment out the rest of the 1turn with my fingertips, ... without too much pain. Tightened the locknut and away I went.

No smoke, but the part-throttle acceleration is more like a healthy gasser now. Very little change as the boost comes on, a smoother transition. I could possibly go further with the ALDA for max. take-off power, but it drives perfect as-is so I'm leaving it alone.

The lesson that I believe I learned is that the transmission in these cars has no torque-sensing to adjust shifting behavior, it relies on the vacuum modulator being matched to the power curve of the engine. In the case of lean/weak off-boost performance, the pedal position (and therefore the vacuum modulator position) is telling the transmission that there is substantial power and to shift accordingly, where my foot was further down than it should be and the power was less than it should be.

So in conclusion, for those awake enough to endure this rambling, an ALDA adjust might be just the thing to help soften those 1-2 shifts, and bring the engine back into spec. / original operating parameters. Might even save that 2nd-gear band from an early grave.

So much for keeping the story short.

- Jeff
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