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Ford is debuting a 10 speed automatic in the Raptor.
What's your take?
I remember reading an interesting article by James May on the subject a few years ago:
http://www.topgear.com/uk/james-may/may-razors-2011
I would need to actually study it, but I start to wonder whether the added time required for a shift (even in a DSG it isn't instant) actually starts to make the car slower? If you have a 3,000rpm [or larger] window of torque (entirely possible with today's engines) but each subsequent gear only gives you 1,000rpm before shifting to the next, is it really beneficial? What's the point of having a wide powerband if it's not even used? You could probably drive a Dodge Viper for years without ever taking it out of 3rd gear and have a perfectly satisfactory motoring experience. (For a diesel that might only have around 1,000rpm of useful torque, I can somewhat understand)
If a CVT is basically "the end" to increases in the number of gear ratios, and they are almost universally loathed, why are engineers steadily approaching an asymptote of gears? I'm sure you can't feel individual shifts in a 10 speed automatic, but I would dare anyone to feel the shifts (shift) of a 2 speed powerglide.
Efficiency is universally improving, but I think that has less to do with gear ratio increases and more to do with better engines and better aerodynamics.
Despite my earlier Dodge Viper reference, 1 speed transmissions are probably too little (although they seem perfectly acceptable for electric cars for some reason, but I digress) and ten speeds are probably too many. So where is the sweet spot? For me somewhere around 5 or 6 gears seems just about perfect...
Thoughts?
What's your take?
I remember reading an interesting article by James May on the subject a few years ago:
A really primitive petrol engine will give maximum torque at one engine speed. As refinements were added, the torque spread across the speed range a bit.
First there were things like automatic ignition advance and retard, which previously was the job of a little lever on the steering wheel. Later, there was variable valve-timing. More recently, there has been the widespread adoption of fuel injection and computer-controlled ignition mapping. All these things have helped spread usable torque across the engine's speed range, to make the car more tractable.
Now we are in an era when motoring writers thrill us with descriptions such as ‘a torque plateau like a cross-section of Norfolk'.
So surely the number of gears we need should be going down. More usable, more flexible grunt should mean less need to muck about with pesky gear ratios. Yet the number of gears is going up.
http://www.topgear.com/uk/james-may/may-razors-2011
I would need to actually study it, but I start to wonder whether the added time required for a shift (even in a DSG it isn't instant) actually starts to make the car slower? If you have a 3,000rpm [or larger] window of torque (entirely possible with today's engines) but each subsequent gear only gives you 1,000rpm before shifting to the next, is it really beneficial? What's the point of having a wide powerband if it's not even used? You could probably drive a Dodge Viper for years without ever taking it out of 3rd gear and have a perfectly satisfactory motoring experience. (For a diesel that might only have around 1,000rpm of useful torque, I can somewhat understand)
If a CVT is basically "the end" to increases in the number of gear ratios, and they are almost universally loathed, why are engineers steadily approaching an asymptote of gears? I'm sure you can't feel individual shifts in a 10 speed automatic, but I would dare anyone to feel the shifts (shift) of a 2 speed powerglide.
Efficiency is universally improving, but I think that has less to do with gear ratio increases and more to do with better engines and better aerodynamics.
Despite my earlier Dodge Viper reference, 1 speed transmissions are probably too little (although they seem perfectly acceptable for electric cars for some reason, but I digress) and ten speeds are probably too many. So where is the sweet spot? For me somewhere around 5 or 6 gears seems just about perfect...
Thoughts?