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Old 12-07-2012, 02:36 PM
Bandem Bandem is offline
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Location: United States
 
Join Date: Aug 2012
Posts: 188
Mein Auto: BMW
Quote:
I have a degree in mechanical engineering which may be part of the reason the shorter explanation works well for me.
Exactly! My point was to explain to everybody, not just scientists. My audience wasn't aimed at you, because you already know far more than this anyway. My explanation was child's play for somebody who has a ME degree, knowing what it involves.

Quote:
Tight gear to gear spacing keeps the fall off less when you shift gears.
Yup, exactly, shorter gearing to keep you closer to peak HP is better. However, you have a limited amount of them, usually 6, so at that point, it will be faster for you to drop off a lot lower RPM's, then shift every 2 seconds, because shifting ultra fast isn't easy.

Quote:
With the DTC the losses of the torque converter are eliminated so the automatic may be quicker if it still has a gearing advantage. Shifts of an automatic are quicker but torque converter automatics are somewhat inefficient due to the need to transfer power through the torque converter.
I may actually edit my post to touch onto this topic. I think TQ automatics are slowly dying off in high-end cars. A lot of high-end cars have """AUTOMATICS""" who only use a torque converter for 1st gear or just getting moving, and then use a full lock-up clutch for everything past. Its a more expensive way, but DCT's and SMG's can all be shifted automatically and still have low power loss.

Oh yeah, and I am also going to add a great reference to my example to give people a sense of reality in acceleration times. From what I found/derived.

I see that ((Velocity^2/2))*(Mass/Power)=Time

Is this right, just to confirm? I want to show people that if you had optimal gearing, it would take a lot less power in cars to accelerate to 60mph (for example). A CVT running at peak HP can cut 0-60times off by as much as half in some cases. A toyota Camry with 200hp can do a 0-60mph in well under 5s with a CVT. Goes to show how critical gearing is, which is why I emphasize it.
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