[theholycow]

Originally Posted by Dragoneye

What? You mean the outrageously flat torque curve?
This is going to sound dumb (just a forwarning), but don't ALL engines HAVE to have a throttle? Throttle, as in that little flap that turns and lets more air in?

No throttle plate. The intake is wide open at all times. It's kinda like a diesel engine with spark plugs and lower compression. The gas pedal operates the fuel injectors, not an intake restriction. According to http://en.wikipedia.org/wiki/Gasoline_direct_injection it can run as lean as 65:1 (hooray for gas savings!). It doesn't say how rich it can run.

Originally Posted by fastball

Yes. I think he just had things mixed up a bit. Most modern engines have done away with the throttle cable, hence the term "drive by wire" technology. The actual throttle still exists, and will untill the 4 stroke internal combustion engine is completely extinct.

Diesel engines, which I'm pretty sure qualify as "4 stroke internal combustion engines", also do not have a throttle plate or throttle body.

You say that most modern engines are drive-by-wire? I thought it was still relatively uncommon, though I don't know that. My VW is DBW and I don't like it.

Originally Posted by camaro5

the valves were computer controlled to open more or less acting just as the old throttle plate has forever.

This is news to me. I hope it's not true and the engine really does operate by enriching or leaning the mixture. Restricting the intake (whether at the intake manifold with a throttle, or at the intake valves as described) is an unnecessary energy loss for a DI engine.