2009 and newer ISx50 paddle shifters shift quicker than 06-08
04-19-11, 04:42 PM
#31
04-19-11, 06:18 PM
#34
The converter itself is locked up, not locked "out"
Which is a feature of all modern torque converters and hass been for decades... it includes a clutch inside the converter that eliminates slippage to improve efficiency.
(the F is just more aggressive about its use)
But it's always "using" the torque converter in all gears, given that's the only thing connecting it to the engine.
04-19-11, 06:28 PM
#35
So to rephrase my question, will the IS-F transmission allow me to upshift to 6th under the stalling speed for that gearing?
In a real manual transmission, my car would stutter and stall.
04-19-11, 06:52 PM
#36
Thanks...was not aware of that. I thought it was a computer controlled manual gearbox. Sorry.
So to rephrase my question, will the IS-F transmission allow me to upshift to 6th under the stalling speed for that gearing?
In a real manual transmission, my car would stutter and stall.
So to rephrase my question, will the IS-F transmission allow me to upshift to 6th under the stalling speed for that gearing?
In a real manual transmission, my car would stutter and stall.
There's no such thing as a "stalling speed" in an automatic in the sense you describe
(there's a "stall speed" of any given torque converter but it has nothing to do with the engine actually stalling, it's something entirely different)
My last car (~500 hp) has an automatic transmission with a manual valve body (meaning you could put it in whatever gear you wanted and it stayed there till you shifted it- but no clutch pedal involved and it has a torque converter)... and I could start from a dead stop in the highest gear no problem (and sometimes did if I forgot to shift down to 1 when stopping at a light).
I probably wouldn't try starting from a dead stop in overdrive gears (which are 7th and 8th gear on an F) because I imagine that'd produce a fair bit of heat in the transmission... but I don't see why it'd have a problem going into 6th anytime you wanted (which is 1:1)
In fact, on a dyno, that's what you'd want it to be in (1:1)
04-19-11, 06:59 PM
#37
There's no such thing as a "stalling speed" in an automatic in the sense you describe
(there's a "stall speed" of any given torque converter but it has nothing to do with the engine actually stalling, it's something entirely different)
My last car (~500 hp) has an automatic transmission with a manual valve body (meaning you could put it in whatever gear you wanted and it stayed there till you shifted it- but no clutch pedal involved and it has a torque converter)... and I could start from a dead stop in the highest gear no problem (and sometimes did if I forgot to shift down to 1 when stopping at a light).
I probably wouldn't try starting from a dead stop in overdrive gears (which are 7th and 8th gear on an F) because I imagine that'd produce a fair bit of heat in the transmission... but I don't see why it'd have a problem going into 6th anytime you wanted (which is 1:1)
In fact, on a dyno, that's what you'd want it to be in (1:1)
(there's a "stall speed" of any given torque converter but it has nothing to do with the engine actually stalling, it's something entirely different)
My last car (~500 hp) has an automatic transmission with a manual valve body (meaning you could put it in whatever gear you wanted and it stayed there till you shifted it- but no clutch pedal involved and it has a torque converter)... and I could start from a dead stop in the highest gear no problem (and sometimes did if I forgot to shift down to 1 when stopping at a light).
I probably wouldn't try starting from a dead stop in overdrive gears (which are 7th and 8th gear on an F) because I imagine that'd produce a fair bit of heat in the transmission... but I don't see why it'd have a problem going into 6th anytime you wanted (which is 1:1)
In fact, on a dyno, that's what you'd want it to be in (1:1)
The reason why the computer shifts from 6th to 5th for example as you keep slowing down is to avoid the stuttering and finally stall. With an automatic and a torque convertor, agreed there is no real stall, but it becomes inefficient. Will the IF-F transmission allow me to shift to a gear that is not recommended for that speed? eg 6th gear at 10mph?
04-20-11, 04:41 AM
#39
Automatics don't stall. because they have torque converters.
It shifts from 6-5 for efficiency and eventual re-acceleration... not to avoid a stall.
A torque converter is not a manual. It won't "shudder and stall" at slow speeds.
04-20-11, 09:52 AM
#40
They are worthless for straight line racing (from a stop), but if you're driving aggressive on the streets, including turning at high speeds, and wanna keep your RPMs high, than it's great. And if you are racing on a roll, then it's quite useful too, you eliminate that initial delay of shifting when you floor it. I imagine they'd be useful on a road course. Technically you could use EC Power, but that's still the ECU controlling it. The paddles give you ultimate control of gear limiting and downshift how you want to. As a driver, you can see what's ahead and what the car should do. That's why the paddle shifters are handy.
04-20-11, 03:01 PM
#41
No, it isn't.
Automatics don't stall. because they have torque converters.
It shifts from 6-5 for efficiency and eventual re-acceleration... not to avoid a stall.
Yeah, that's what I just said...
Again, I don't see why not. For that matter you SHOULD be able to start from a dead stop in 6th if you wanted, it'd just be pretty slow and inefficient.
A torque converter is not a manual. It won't "shudder and stall" at slow speeds.
Originally Posted by chikoo
Will the IF-F transmission allow me to shift to a gear that is not recommended for that speed? eg 6th gear at 10mph?
Will the IF-F transmission allow me to shift to a gear that is not recommended for that speed? eg 6th gear at 10mph?
It shifts from 6-5 for efficiency and eventual re-acceleration... not to avoid a stall.
Yeah, that's what I just said...
Again, I don't see why not. For that matter you SHOULD be able to start from a dead stop in 6th if you wanted, it'd just be pretty slow and inefficient.
A torque converter is not a manual. It won't "shudder and stall" at slow speeds.
04-20-11, 03:04 PM
#42
They are worthless for straight line racing (from a stop), but if you're driving aggressive on the streets, including turning at high speeds, and wanna keep your RPMs high, than it's great. And if you are racing on a roll, then it's quite useful too, you eliminate that initial delay of shifting when you floor it. I imagine they'd be useful on a road course. Technically you could use EC Power, but that's still the ECU controlling it. The paddles give you ultimate control of gear limiting and downshift how you want to. As a driver, you can see what's ahead and what the car should do. That's why the paddle shifters are handy.
Like every other technology solutions, the end result is how one adapts with the technology at hand. A creative driver will combine the ECU's recommendations to upshift with his/her need to downshift on demand, within the constraints set by the system to not destroy itself ie. not let you Rev over redline nor let you shift into a higher gear that will stall.
04-20-11, 03:19 PM
#43
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That is why the paddle shifters on the ISx50 are utterly useless.
04-20-11, 03:38 PM
#44
^^ Correct... as Kurtz and other mentioned...
All that does is sets a specific gear limit which the ECU is allowed to choose from. When you "downshift" with paddle/shifter, you just lowered the limit of a gear. You can literally downshift by forcing the ECU to use the lower gear from the range it is allowed to choose from.
Upshifting just raises the gear limit, but ECU decides which gears to use with the higher range you gave it by "upshifting". For example, you can hit the + on your paddle to gear 4 but the car can still be in 2 or 3rd gear depending on how the ECU decides.
That's again why paddle shifters are useless on our car and possible used only for downshifting purpose.
All that does is sets a specific gear limit which the ECU is allowed to choose from. When you "downshift" with paddle/shifter, you just lowered the limit of a gear. You can literally downshift by forcing the ECU to use the lower gear from the range it is allowed to choose from.
Upshifting just raises the gear limit, but ECU decides which gears to use with the higher range you gave it by "upshifting". For example, you can hit the + on your paddle to gear 4 but the car can still be in 2 or 3rd gear depending on how the ECU decides.
That's again why paddle shifters are useless on our car and possible used only for downshifting purpose.
04-20-11, 06:01 PM
#45
^^ Correct... as Kurtz and other mentioned...
All that does is sets a specific gear limit which the ECU is allowed to choose from. When you "downshift" with paddle/shifter, you just lowered the limit of a gear. You can literally downshift by forcing the ECU to use the lower gear from the range it is allowed to choose from.
Upshifting just raises the gear limit, but ECU decides which gears to use with the higher range you gave it by "upshifting". For example, you can hit the + on your paddle to gear 4 but the car can still be in 2 or 3rd gear depending on how the ECU decides.
All that does is sets a specific gear limit which the ECU is allowed to choose from. When you "downshift" with paddle/shifter, you just lowered the limit of a gear. You can literally downshift by forcing the ECU to use the lower gear from the range it is allowed to choose from.
Upshifting just raises the gear limit, but ECU decides which gears to use with the higher range you gave it by "upshifting". For example, you can hit the + on your paddle to gear 4 but the car can still be in 2 or 3rd gear depending on how the ECU decides.
Give me one example when you would need to upshift and the computer decides it should still be in the lower gear and I will agree with you.