Quote:
Originally Posted by Fat Charlie
My first reaction is to wince, because CVT. It's a great idea but mechanically, nothing beats an actual box of gears. It's the old rule that In theory, there's no difference between theory and practice. In practice, there is.
Taller gearing only matters in lowest gear and highest gear. It's great in fifth, and in first... at least with an MT you're already in first, while the guy next to you is hoping his TCM helps him out a bit. In between low and high, it's your responsibility to juggle power output and gearing. If you want to simply floor it and have the power, buy an electric. It's the right tool for that job.
Until I get a Tesla, I'm in a manual. The limitations of gas engines and my requirement for responsiveness dictate it. If I need to downshift before stomping, so be it- I'll still get the results I want faster and better than an AT or CVT. When I finally get an electric, I can finally give up babysitting the powertrain.
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I agree that gears are better and I prefer the feel of a solid connection over a CVT or auto with an unlocked torque converter, but I don't hate the feel of a CVT and I can live with the less direct feel if it provides a tangible improvement in performance and efficiency, but a CVT is heavier and isn't nearly as mechanically efficient as a manual so in practice a manual may be the fastest and most efficient.
As for the gearing, unfortunately things aren't that simple. Transmissions that are geared taller often have wider spaced gears, so the engine will be at a lower RPM after a shift and therefore acceleration will suffer. For example, let's say I am racing someone from a stop. With an EX transmission, I could reach 36 MPH in first gear and be at 4120 RPM after I shift to second. With the taller geared HX transmission I could reach 37 MPH in first, almost the same. However, when I shift to second, I would be down to 3451 RPM. That's going to hurt acceleration.
Another scenario- Let's say I am getting onto the highway at 40 MPH. That's too fast for first gear on either transmission, so the lowest gear I could choose would be second. With the EX transmission I would be at 4578 RPM, pretty decent. However, with the HX transmission, I would only be at 3731 RPM. The difference in power between 4600 RPM and 3700 RPM is dramatic with my engine.
With a CVT I could floor it going 40 and almost instantly be at 6K plus RPM, which is a dramatic difference compared to the 4600 I could be at with a manual and also drop my cruising RPM significantly. Best of both worlds! In theory anyways. In reality the manual transmission is going to be the clear winner if the CVT takes a crap and leaves me on the side of the road. Also, considering the superior efficiency and lower weight of a manual transmission, the difference in real world performance and efficiency differences between the manual and the CVT may not be as much as I think.