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Thread: 812 Superfast

  1. #11
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    I had to google CV. So bottom line, Ferrari measures their HP, then exaggerates the hell out of it like they always do, to get to 790. Then they round it up to 800 "for tax purposes" in Italy, and voila, 800 HP! So there's your 8.

    I'm betting the car should be called something more like a "7.512" LOL

    French and Italian tax horsepower (CV)

    In addition, the capital form CV is used in Italy and France as a unit for tax horsepower, short for, respectively, cavalli vapore and chevaux vapeur (steam horses). CV is a non-linear rating of a motor vehicle for tax purposes.[20] The CV rating, or fiscal power, is {\displaystyle \scriptstyle \left({\tfrac {P}{40}}\right)^{1.6}+{\tfrac {U}{45}}}, where P is the maximum power in kilowatts and U is the amount of carbon dioxide (CO2) emitted in grams per kilometre. The term for CO2 measurements has been included in the definition only since 1998, so older ratings in CV are not directly comparable. The fiscal power has found its way into naming of automobile models, such as the popular CitroŽn deux-chevaux. The cheval-vapeur (ch) unit should not be confused with the French cheval fiscal (CV).
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  2. #12
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    Quote Originally Posted by Birdman View Post
    I had to google CV. So bottom line, Ferrari measures their HP, then exaggerates the hell out of it like they always do, to get to 790. Then they round it up to 800 "for tax purposes" in Italy, and voila, 800 HP! So there's your 8.

    I'm betting the car should be called something more like a "7.512" LOL

    French and Italian tax horsepower (CV)

    In addition, the capital form CV is used in Italy and France as a unit for tax horsepower, short for, respectively, cavalli vapore and chevaux vapeur (steam horses). CV is a non-linear rating of a motor vehicle for tax purposes.[20] The CV rating, or fiscal power, is {\displaystyle \scriptstyle \left({\tfrac {P}{40}}\right)^{1.6}+{\tfrac {U}{45}}}, where P is the maximum power in kilowatts and U is the amount of carbon dioxide (CO2) emitted in grams per kilometre. The term for CO2 measurements has been included in the definition only since 1998, so older ratings in CV are not directly comparable. The fiscal power has found its way into naming of automobile models, such as the popular CitroŽn deux-chevaux. The cheval-vapeur (ch) unit should not be confused with the French cheval fiscal (CV).
    you've given this far too much thought.
    Why yes! That was me passing you on the outside of 6.

  3. #13
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    Quote Originally Posted by Birdman View Post
    I had to google CV. So bottom line, Ferrari measures their HP, then exaggerates the hell out of it like they always do, to get to 790. Then they round it up to 800 "for tax purposes" in Italy, and voila, 800 HP! So there's your 8.

    I'm betting the car should be called something more like a "7.512" LOL

    French and Italian tax horsepower (CV)

    In addition, the capital form CV is used in Italy and France as a unit for tax horsepower, short for, respectively, cavalli vapore and chevaux vapeur (steam horses). CV is a non-linear rating of a motor vehicle for tax purposes.[20] The CV rating, or fiscal power, is {\displaystyle \scriptstyle \left({\tfrac {P}{40}}\right)^{1.6}+{\tfrac {U}{45}}}, where P is the maximum power in kilowatts and U is the amount of carbon dioxide (CO2) emitted in grams per kilometre. The term for CO2 measurements has been included in the definition only since 1998, so older ratings in CV are not directly comparable. The fiscal power has found its way into naming of automobile models, such as the popular CitroŽn deux-chevaux. The cheval-vapeur (ch) unit should not be confused with the French cheval fiscal (CV).
    Next time we go out for breakfast, I'm going to ask you to explain this to me and give me an actual number to plug into the equation. I'll ask the waitress for a pencil and you can figure it out on a napkin for me.

  4. #14
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    Quote Originally Posted by Trackman View Post
    you've given this far too much thought.
    No, I just copied that shit from wikipedia. I just wanted to know what CV was. And the answer is that it's a "rounded up" horsepower figure for Italian tax purposes. Since we know that Ferrari always exaggerates their HP figures (as opposed to Porsche who underestimates theirs) and then they round them up for CV....the 800 is wildly enthusiastic.

    Quote Originally Posted by Fireman View Post
    Next time we go out for breakfast, I'm going to ask you to explain this to me and give me an actual number to plug into the equation. I'll ask the waitress for a pencil and you can figure it out on a napkin for me.
    I never said I understood it!
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  5. #15
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    Quote Originally Posted by Birdman View Post
    I never said I understood it!
    If you talk the talk, you have to walk the walk.

  6. #16
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    Quote Originally Posted by Birdman View Post
    I never said I understood it!
    I don't understand either. The formula you copied uses Kilowatts, not HP, and includes an artificial increase with CO2 output (obviously to punish cars with bad emissions). They can't be using CV as calculated using that formula, because by plugging in the 789 hp published (converting it to 588.357 kW), the CV calculates out to 73.8 + the C02 term. In order for that to equal 800, the car would have to be putting out over 79 pounds of CO2 per kilometer!

    But, let's go the other way. Average CO2 per kilometer in Italy is 118 (thanks, Google!). Let's say the Ferrari is a bit higher, at, I don't know, 140. Plugging that in and working forward gives us a CV of 76.9. Hmm, wait, that seems awful close to 80. Let's work the equation assuming a CV if 80... CO2/km calculates out at 279g. More Google. Ok, looks like Ferrari is averaging 250-300 CO2/km for 2017 models. That checks out.

    So... I think we have our answer. The CV is 80, not 800. Still works for the explanation of where the 8 came from.
    ďI enjoy talking to you. Your mind appeals to me. It resembles my own mind except that you happen to be insane.Ē
    ― George Orwell, 1984

  7. #17
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    Both of you need to get back to work.

  8. #18
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    Quote Originally Posted by Badman View Post
    I don't understand either. The formula you copied uses Kilowatts, not HP, and includes an artificial increase with CO2 output (obviously to punish cars with bad emissions). They can't be using CV as calculated using that formula, because by plugging in the 789 hp published (converting it to 588.357 kW), the CV calculates out to 73.8 + the C02 term. In order for that to equal 800, the car would have to be putting out over 79 pounds of CO2 per kilometer!

    But, let's go the other way. Average CO2 per kilometer in Italy is 118 (thanks, Google!). Let's say the Ferrari is a bit higher, at, I don't know, 140. Plugging that in and working forward gives us a CV of 76.9. Hmm, wait, that seems awful close to 80. Let's work the equation assuming a CV if 80... CO2/km calculates out at 279g. More Google. Ok, looks like Ferrari is averaging 250-300 CO2/km for 2017 models. That checks out.

    So... I think we have our answer. The CV is 80, not 800. Still works for the explanation of where the 8 came from.
    We have a new napkin equation winner!

  9. #19
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    Quote Originally Posted by RichMan View Post
    Both of you need to get back to work.
    Come on, I'm an engineer, I did math... I gotta be able to expense that time to one of my clients, right?
    ďI enjoy talking to you. Your mind appeals to me. It resembles my own mind except that you happen to be insane.Ē
    ― George Orwell, 1984

  10. #20
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    Wait a minute. More C02 gives more CV? How is that punishing anyone?
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