What will the "Gas Guzzler Tax" be
#16
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#18
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Nope, the manual is still slightly more efficient (that's why the top speed for the manual is 2 kph higher than PDK-S - slightly less power loss due to internal friction)...
But the fuel economy numbers for the PDK are a little better than the manual, because it has an auto mode that short-shifts (I guess this is the reason or some other compatibility with the way the tests are administered). Having 7 gears helps too, although top gear is virtually the same in each.
But the fuel economy numbers for the PDK are a little better than the manual, because it has an auto mode that short-shifts (I guess this is the reason or some other compatibility with the way the tests are administered). Having 7 gears helps too, although top gear is virtually the same in each.
If the manual was more "efficient" it would get better gas mileage.
7 Speed manual RPM @ 70 MPH = 2100
7 Speed PDK RPM @ 70 MPH = 1900
#19
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The Gas Guzzler Tax has been part of the MSRP on the Monroney/window sticker of applicable vehicles for decades. Nothing has changed since the 997.
#20
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Manual has higher frictional and rotational inertia losses vs. PDK. It's the gearing that is different that accounts for speed delta. Shorter final gear ratio in the manual.
If the manual was more "efficient" it would get better gas mileage.
7 Speed manual RPM @ 70 MPH = 2100
7 Speed PDK RPM @ 70 MPH = 1900
If the manual was more "efficient" it would get better gas mileage.
7 Speed manual RPM @ 70 MPH = 2100
7 Speed PDK RPM @ 70 MPH = 1900
Your example above is comparing two irrelevant ratios - neither PDK nor manual achieves top speed in 7th gear for a non-GT model. Try comparing 6th gears.
The additional internal friction in the PDK is also the reason that they have an additional central cooler in most models and still are subject to more over-heating at the track than manual. Cars like the Cayman R exhibit this clearly.
The reason PDK does so well in the mpg tests has to do with the testing protocols, afaik...
#22
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EFF GREEN TAXES.
#24
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Apparently McLaren models just make it over the threshold.
The data in this article is a few years old, but they explain why the GGT is such a sham...
Even though the mpg numbers for Highway, City and Combined fuel economy ratings that you see on a new car's window sticker come from the EPA, they are not the same figures used to calculate the GGT. Basically, the EPA uses pure laboratory testing to glean its fundamental mpg ratings, but for the purposes of window stickers, it also factors in three other testing protocols to better replicate real-world driving. However, for reasons that are not made immediately clear in the documentation (but probably with roots in some serious lobbying dollars), the GGT is factored on the lab numbers alone, which are more lenient.
http://www.autoblog.com/2014/07/24/c...zler-tax-list/
The data in this article is a few years old, but they explain why the GGT is such a sham...
Even though the mpg numbers for Highway, City and Combined fuel economy ratings that you see on a new car's window sticker come from the EPA, they are not the same figures used to calculate the GGT. Basically, the EPA uses pure laboratory testing to glean its fundamental mpg ratings, but for the purposes of window stickers, it also factors in three other testing protocols to better replicate real-world driving. However, for reasons that are not made immediately clear in the documentation (but probably with roots in some serious lobbying dollars), the GGT is factored on the lab numbers alone, which are more lenient.
http://www.autoblog.com/2014/07/24/c...zler-tax-list/
#25
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#27
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Originally Posted by Spyerx
EFF TAXES IN GENERAL.
#28
In light of the fact that annual registration of a car like this in the Republic of Kalifornia costs almost this much, it's just another drop in the bucket. Paid about $625 today to renew the registration on my 2014 C2S.
#30
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^ I expect it will be higher with the manual transmission, but we shall see...