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Fuel Economy

well the LT4 in a ZL1 is around 14 city/20 highway and the CTS-V 3rd gen is 14 city/21 highway. I'd expect the CT5 is somewhere around there.
 
those numbers really screwed me up for a minute in the article hahahaha....wasn't expecting to see liters per 100km
 
Kind of shocking that the automatic MPG got worse from the ATS-V to the CT4V-BW, considering they moved to the 10 speed transmission. There is only a 7 or 8 HP bump, which is basically rounding error. Maybe the higher weight or increased downforce (and resulting drag) is the culprit?
 
I know the chip shortage has been having an impact on fuel economy for some other cars and trucks, I wonder if that has something to do with it. In any case, looks like the 4 is definitely in range of the gas guzzler tax...
 
Remember that the EPA numbers on the window sticker are NOT the numbers used to calculate the gas tax. The EPA city and highway numbers are run on a dyno without A/C, etc. The dyno numbers are calculated and then three additional tests are performed, one at cold ambient temps, one with A/C, and one with high speeds and acceleration to better capture how vehicles perform in the real world. The dyno numbers are then decremented by the results of the additional three tests for the window sticker.

The gas guzzler tax does NOT include these three additional tests, it just uses the dyno numbers. The real world numbers are typically 70-90% of the dyno numbers for the city rating, and 70-80% for highway. It also has a correction based on number of vehicles produced. If the Blackwing represents a small number of the total fleet vehicles, it may get a small boost reflecting its limited nature.

The CT4 V BW automatic will most likely escape the GGT, the manual is probably right on the border. The CT5 V BW will certainly have a GGT.

For a real world example, Ford was charging a GGT on the Mach 1 with auto tranny, which has a real world fuel economy of 15/18/23: exactly the same as the CT4 V BW manual. At some point, they stopped charging the GGT and refunded the early customers. The manual version had the GGT throughout.
 
Remember that the EPA numbers on the window sticker are NOT the numbers used to calculate the gas tax. The EPA city and highway numbers are run on a dyno without A/C, etc. The dyno numbers are calculated and then three additional tests are performed, one at cold ambient temps, one with A/C, and one with high speeds and acceleration to better capture how vehicles perform in the real world. The dyno numbers are then decremented by the results of the additional three tests for the window sticker.

The gas guzzler tax does NOT include these three additional tests, it just uses the dyno numbers. The real world numbers are typically 70-90% of the dyno numbers for the city rating, and 70-80% for highway. It also has a correction based on number of vehicles produced. If the Blackwing represents a small number of the total fleet vehicles, it may get a small boost reflecting its limited nature.

The CT4 V BW automatic will most likely escape the GGT, the manual is probably right on the border. The CT5 V BW will certainly have a GGT.

For a real world example, Ford was charging a GGT on the Mach 1 with auto tranny, which has a real world fuel economy of 15/18/23: exactly the same as the CT4 V BW manual. At some point, they stopped charging the GGT and refunded the early customers. The manual version had the GGT throughout.
Awesome info @Ryan thank you.
 
At most 1300 for the 6sp and less for the automatic. And according to the article above it should be less than that based on only dyno numbers.
 
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I'm not 100% of this, but I thought the CTS-V gas guzzler was $1,700 at the end of its run. The 6-speed ct5 blackwing gets slightly worse mileage, so I'm anticipating $1,700 as the minimum. Be happy to be wrong though.
 
Seems like good news for the CT4 folks - per fueleconomy.gov, both transmissions escape the gas guzzler tax.

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Potentially bad news for the CT5 - the site just says 'Yes' for gas guzzler with no value - I went looking for comparisons and the 2020 Challenger Hellcat Widebody auto is 13/15/21 - same numbers as the manual CT5BW, and it gets tagged with $2100. Here's hoping the dyno numbers drop it down rather than up!
 
Seems like good news for the CT4 folks - per fueleconomy.gov, both transmissions escape the gas guzzler tax.

View attachment 3557


Potentially bad news for the CT5 - the site just says 'Yes' for gas guzzler with no value - I went looking for comparisons and the 2020 Challenger Hellcat Widebody auto is 13/15/21 - same numbers as the manual CT5BW, and it gets tagged with $2100. Here's hoping the dyno numbers drop it down rather than up!
Good look here is to hoping that's correct!!!!
 
I am assuming we expect the CT5 manual to have the 1-4 skip shift? I'm new to GM products but feel like I have been reading about it since the C5 Corvette. And yes, I know about the eliminator.
 
I am assuming we expect the CT5 manual to have the 1-4 skip shift? I'm new to GM products but feel like I have been reading about it since the C5 Corvette. And yes, I know about the eliminator.
I don't see where the eliminator is even necessary. In my ZL1 1LE, a message shows up on the dash, which I ignore, and shift as I want to. It doesn't force you to do anything. Unless that message on the dash really gets under your skin...
 
I am assuming we expect the CT5 manual to have the 1-4 skip shift? I'm new to GM products but feel like I have been reading about it since the C5 Corvette. And yes, I know about the eliminator.
I’m sure someone will chime in with a for sure answer, but I believe I remember reading somewhere (possibly from Mirza) that it will not have the 1-4 skip
 
1-4 skip shift?

It's a "feature" that's been with the 6 speed transmission in Corvettes since its introduction in 1989 in order to meet emissions standards. It's carried over to other cars that use related powertrains. Under certain conditions, it locks you out of 2nd and 3rd gears, and forces you from 1st into 4th. It's gotten better over the years--my dad has had C4, C5, and C6 Corvettes that all had it, along with a 2nd gen CTS-V, and the later ones were definitely less obnoxious than the earlier ones. There is a defeat mechanism that you can buy aftermarket and is fairly easy to install. I think he had it installed on his 91 and 03, but by his 06, 13, and the V it was benign enough that he just left well enough alone and dealt with it. It cuts out under heavy acceleration, so you can just give it a little extra gas to push through it.
 

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