When do you normally shift gears from 1st to 2nd and 2nd to 3rd etc? I shift at 4,000 RPM. Is this ok, or should it be a higher number or lower? Also, when driving do you keep the RPMs at around 3-4,000? Thanks, -Bob.
It depends on how you're driving. These cars and engines do love to be stretched out. Don't be nervous about sweeping the tach towards redline. In fact, the engines are built for this, and it is good for the cars to give them a workout. Think of the engine in the car as the heart in your body. Plus, get that engine going and your heart will follow.
There is no correct RPM to shift at, except of course to avoid stalling (too low a RPM), or redlining (too high a RPM). With computer-assisted transmissions, you can't do either of those as it won't let you.
On the other hand, if you're racing, I suppose you shift as close to redline as you can. Also to keep in mind, you burn more fuel the closer to redline you are, so, if you don't mind filling up more often, you could cruise in 3rd gear on the freeway.
The point of where you shift is to choose where in the powerband you are in the next gear.
If power is what you're after, near redline is your friend.
If its fuel economy, which as I remember engines are at their peak efficiency at their peak torque. In looking at the dyno results posted, the torque powerband is pretty even from 4000-5500 rpm, so this range should work best for fuel economy under acceleration.