Percentage Drvetrain Loss for Auto Cars
#16
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Lots of engines have been dyno'ed, the problem is that there are significant differences between dynos and engines (and seasons, altitude, and also local fuel: see e.g. California).
What we need is a volunteer to dyno their car, then swap the 5-speed for an auto (or vice-versa) and test again, then swap back as a double-check. What do you think? Are you game? Cool!!
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What we need is a volunteer to dyno their car, then swap the 5-speed for an auto (or vice-versa) and test again, then swap back as a double-check. What do you think? Are you game? Cool!!
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#17
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#18
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Hmmm...my hopes and dreams were crushed ages ago.
So, the Rogerbox in the Red Witch runs on bad decisions.
Those are still alive and go right through to the rear wheels.
Seth K. Pyle
So, the Rogerbox in the Red Witch runs on bad decisions.
Those are still alive and go right through to the rear wheels.
Seth K. Pyle
#20
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This is not going to end well with Roger............methinks he would argue to the contrary, as I do. You have to compare the comfort of a fully equipped 928 vs the do it yourself manual transmission; especially when you are on a highway parking lot moving seven feet at a time for almost two hours like I was in Chicago Friday afternoon. I wouldn't have had a 5-speed for all the money in the world after it took took nearly two hours to traverse 21 miles. I'll take the 15% loss in HP and still have a left calf muscle that I can use at nearly 70 years of age. Just say'in.
#21
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A good friend owned a dyno and has run several hundred cars
about 15% for a manual and 20-23% for a auto .
autos can vary depending on torque converter loss
about 15% for a manual and 20-23% for a auto .
autos can vary depending on torque converter loss
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I'm here!! Finished stuffing myself with Turkey.
The"loss" is all in the hands of the driver. No "loss" with a Rogerbox because there is no room for error.
However about 25% loss with a "crapbox" while the "I have a larger ***** wantobe's" try and master the worst manual gearbox ever known to the automobile World.
Back to your normal viewing pleasure!
The"loss" is all in the hands of the driver. No "loss" with a Rogerbox because there is no room for error.
However about 25% loss with a "crapbox" while the "I have a larger ***** wantobe's" try and master the worst manual gearbox ever known to the automobile World.
Back to your normal viewing pleasure!
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Does it have the "Do It Yourself" manual transmission, or the superior "Fully Equipped by Porsche" Automatic Transmission?
George Layton March 2014
928 Owners are ".....a secret sect of quietly assured Porsche pragmatists who in near anonymity appreciate the prodigious, easy going prowess of the 928."![thumbsup](https://rennlist.com/forums/graemlins/bigok.gif)
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Does it have the "Do It Yourself" manual transmission, or the superior "Fully Equipped by Porsche" Automatic Transmission?
![thumbsup](https://rennlist.com/forums/graemlins/bigok.gif)
928 Owners are ".....a secret sect of quietly assured Porsche pragmatists who in near anonymity appreciate the prodigious, easy going prowess of the 928."
![thumbsup](https://rennlist.com/forums/graemlins/bigok.gif)
#29
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Why do automatic transmission NEED to have coolers ?? Very simple the pumps and torque convertor churning up the oil turns kinetic energy into HEAT and that heat needs to be WASTED .....so yes they are less efficient by design.
If the old Mercedes auto units are so good why all the development over the last 20 years of the dual clutch automatic shifting MANUAL transmissions ???? Oh right because those who occasionally try to drive a manual transmission find it too difficult to remember where the next gear is or forget to push in the clutch as they come to a stop
So for those challenged drivers you simply put it in D ......
And yes my daughters Nissan GTR has the dual clutch
only because that is all they offered.
If the old Mercedes auto units are so good why all the development over the last 20 years of the dual clutch automatic shifting MANUAL transmissions ???? Oh right because those who occasionally try to drive a manual transmission find it too difficult to remember where the next gear is or forget to push in the clutch as they come to a stop
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And yes my daughters Nissan GTR has the dual clutch
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#30
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Too bad a transmission couldnt be hooked up directly to some sort of dyno that feeds it a known input ....then on the other end the output could be measured. Only real way to determine losses on the actual transmission i would guess?
Just make sure you motor makes enough...then you don't have to worry about it
Just make sure you motor makes enough...then you don't have to worry about it
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