How a Car Engine Works

I'm going to suggest that if you want to call yourself an engineer in any field, you should be able to quickly understand, among other things, how engines and air conditioning work. If not, there's always the management track ;) Good to see there are some other gearheads here.

The only time I have stalled out is when I am pulling away in first and let the clutch come up to fast. If you are stalling your engine going from 1st to 2nd you are doing something wrong, since the wheels are moving at that point. Even if you let the clutch come up too fast the engine won't stall because the wheels will keep turning it. It might shudder and definitely not like the low RPM's, but it shouldn't stall.

With a manual all there is between the engine is the clutch and the transmission. When the clutch is engaged your engine to your wheels is a single straight line (with some gears in between, but lets ignore those for now). If your engine has a lot of power it will simply turn the wheels, however in most cases the engine is just simply not strong enough to break the friction of the tires agains the ground, especially in lower RPM's.

When you slowly let the clutch up, what you are doing is having the engine turn faster than the pipe connected to the wheels, by using some friction material you transfer SOME of the power from the engine to the pipe connected to the wheels, as you continue rolling eventually the pipe connected to the wheels catches up and spins at the same speed as the engine (once again, ignore gearing), at that point you can let the clutch up entirely (thereby basically connecting it directly).

When you go from first to second, you use RPM matching to have the engine spin at the same speed as the pipe on the other end. When the RPM's match, you let the clutch up and from there you can start providing more power by pushing the gas pedal.

See more about clutch construction here: http://en.wikipedia.org/wiki/Clutch

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In most automatics there is a device called a torque converter that takes care of the friction part of the clutch for you. Interestingly enough it does this using fluid rather than friction material. There are fins on both sides of the torque converter, the two sides can freely spin. One side is connected to the engine, the other side is connected to the gear box. As you press the gas pedal, one side forces fluid through a series of fins, this whips the fluid into motion, this fluid is then forced through another series of fins on the other half. Because of the pressure difference in the fluid it will eventually have enough power to start forcing the other side (attached to the gear box and the wheels) to start moving. At some point the engine side is spinning just as fast as the wheel side, at that point most torque converters will actually lock. Now the torque convertor is directly connecting the engine to the transmission to the wheels.

When it switches gears, it disengages the torque converter lock, lowers the engine RPM's (even if you keep pressing the gas, it will use the computer to inject less gas temporarily), switch gears in the gear box, let the torque converter do it's thing, and once RPM's match closely re-engage the torque convertor lock.

See: http://en.wikipedia.org/wiki/Torque_converter

That's one of the major reasons the GT-R is so quick off the line and down the quarter mile.

It was the first production car with a dual-clutch transmission that was actually realistically priced, and it's still arguably the most cost-effective.

That would probably just serve to confuse people, as it's essentially two VR* engines grafted together. The VR6 is, while more common than the W's, still fairly obscure even within the VAG line of autos, and certainly outside of it.

So, yes, they're cool machines, but probably not a whole lot of utility in this context as they work the same way, but in a funky shape :)

Thank you very much! I'm trying to get better at understanding how cars work and this presentation helps immensely.