When I put the pedal to the floor of my SDL in 'D', she climbs to about 4900 rpm in every shift.

When I keep my foot pressed to the floor in '2' or '3', power lets off around 5100 rpm, but climbs up to about 5300 rpm (5150 rpm +- 150, right? I think it's the overboost protection). How would I get my SDL to shift later than it shifts now?

My sister has an '87 300D turbo that shifts at 4600 rpm for every shift, too. Doesn't even make it close to the dots on the speedometer.

I have seen these six-cylinders shift normally in excess of 5000 rpm. Why can't mine do that?

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1987 300SDL (324000)

1986 Porsche 951 (944 Turbo) (166000)

1978 Porsche 924 (99000)

1996 Nissan Pathfinder R50 (201000)