[Christ]

Originally Posted by greasemonkee

The only problem I see with simply adding a fixed resistance to the throttle pedal is this: at 1500 rpm & 20% throttle position would be lets say 7in/hg manifold pressure. At 2000 rpm 20% throttle position may be 12in/hg man pressure. So you see the trend anyway. I question whether any fixed force is gonna cut it. In the picture I drew out, you'll have the same amount of force pushing back on the gas pedal at all rpm for a given load. Turn on the headlights and AC and it will push back that much more.

I like the feedback a little caster gives the steering and the feedback I get from pushing the brakes harder. Why not feedback from the throttle? In fact, I would be surprised if someone somewhere in racing isn't using something similar so the driver has an idea how much torque he's putting on the ground.

That air sack thing increases feedback with an increase in positive pressure against it, something about the shape, I think.

How I imagine it works (without looking):

Since it's shaped like a pillow, wider than thick, you're applying a lot of pressure to a large area (by pushing on the pedal) which makes the air attempt to "get out of the way". That forces the sides to expand slightly, and the air compresses slightly. Since you're attempting to expand an area physically more resistive than the area that you're pushing on, it creates a leveraged pressure effect, sort of like working a hydraulic jack, only in reverse (where you're making the larger surface area work the smaller surface area).