w108 sluggish uphill

[n10]

So I finally have my w108 280s up and running "well".

I drove all over the place yesterday but going uphill sucks. A few things I know...

-The plugs, wires, distributor cap and rotor are all new.
-Exhaust is shot. When I floor it, its loud as hell. Saturday night at the drag strip style but with little get up and go.
-Idle is nice and smooth
-It doesnt seem to want to downshift (auto tranny) going up hill even with the gas floored.

Flat groud driving seems ok but I really dont have an idea of how quick it should be normally.

BTW what is the little "button" behind the gas pedal on the firewall? Its toward the top of the pedal.

Any insight would be appreciated!
-Nate

[berfinroy]

The 280 S 6 cylinder engine displaces only 170 ci, and has very modest low end torque. It needs lots of revs to do anything. Even then, Maximum horespower at high rpm (say, 6000rpm) is only about 150 to move a sedan weighing around 3700-3800lb. Its not a fast car.
To get anything resembling "performance", you have to keep the revs up, which means controlling the automatic transmission's shift points as much as possible.
The button under the throttle is a switch to make the transmission downshift "automatically" under full throttle, but the moment you lift off it willpromptly upshift again.....not like US automatics of the day that usually provided partial throttle automatic downshifts.

[n10]

Ah ok, good to know. I figured the button was for a downshift but wasnt positive. No doubt that low end is modest, 0 to 60 in like 2 min
My DD is a twin turbo A6 so I guess Im used to getting there abit quicker with less effort.

Now controlling the downshift on the selector, is it ok to do that on the fly or should I be letting off the gas first?