Captain Ned wrote:Pancake wrote:Chrispy_ wrote:Interesting comments from Synthetel2 about gas pedals being closer to binary than linear; I don't think I've ever owned a car with an electronic throttle, so that kind of figures - where just 10% throttle = 90% peak torque at that engine speed.
Interesting comment but complete crap. The throttle exists to make fuel-to-air ratio combustible in petrol engines, which is in a fairly narrow range compared to diesels. My car has an electronic throttle and I know it quite well as I pull it apart and service it with love and care and sweet tenderness... Anyway, throttles are most definitely not "binary" in how they work. The clever little computer in my car modulates the throttle (in conjunction with mass air flow sensor) to give the perfect blend of air and fuel to keep each cylinder (multipoint EFI) burning happily at the required torque output at current RPM as demanded by my right foot. It's a beautiful thing.
Partially correct (the complete crap comment is incorrect). Modern TBW systems not only manage fuel-air ratios but also manage torque output by proportioning physical throttle-plate movement to actual gas pedal movement, and this management occurs to ensure that the engine never sends torque to the transmission that would exceed the transmission's torque rating.
In other words, it reduces torque by reducing fuel and air which is burnt to generate said torque... So, what are you describing is an effect of having a computer management the power output of the engine. However, the actual physical purpose and function of the throttle is still simply this - to ensure fuel-to-air ratio is combustible in a petrol engine. i.e. I am COMPLETELY correct.