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How C8 does 0--60 in under 3.0

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  • How C8 does 0--60 in under 3.0



    12:35
    YouTube - 13 hours ago
    Last edited by John; 07-25-2019, 01:43 AM. Reason: Thanks SheepDog; reinserted your video than must have gone missing when we had our maintenance issue for a couple of hours.

  • #2
    Bikerjulio gave me my Avitar. He was curious about he 0-60. I posted this to repay him.

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    • #3
      I watched the video as I have watched many of Jason's. I felt that with this one he gave (as usual), an excellent run through some of the theory behind traction and acceleration, particularly as it relates to mid-engined cars in general.

      However it seemed to me like it was part one of two, the second part being more specifically about the C8.

      And by that I mean that he needs to model the C8's 0-60 time taking into account it's weight, rear wheel HP, tire contact patch, and plausible gearing. All these are known or can be reasonably estimated and differ from the C7 example that he used to derive some of the numbers. Note that he avoided talking about actual power numbers for instance.

      We won't know until some stock examples on stock tires have been independently tested, and notwithstanding the video, I continue to have doubts that 495 HP can shift a car of that mass to a sub 3 sec 0-60. I'd like to see Jason do a follow-up to address this as well.
      2020 C8 Corvette.D.O.B 2/03/2020
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      • #4
        As precise as the figures are in the Videos math. I am surprised that a 40/60 weight front to rear ratio is used in the calculations when the real ratio is 41/59 front to rear ratio.

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        • #5
          "...shifts in 100 milliseconds....."
          2018 Grand Sport, Torch Red, black int, A8, Nav/PDR

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          • #6
            It's a surprising 0-60 claim and need to be tested. For sure.

            Looked again. Jason does not talk about the weight of either vehicle, Zr1 or C8. He talked about the respective weight distributions front to rear, as 50/50 v 40/60. Seems to me that Hp to total weight ratio is something that usually most folks gabber about in this kind of analysis.

            But what do I know? I speculate.

            Speculate. HP does not matter, in this application.
            I speculate. It is all about Torque, in this application: 0-60
            The torque raw is 470 ft Lb. That is the raw Torque before the 470 gets multiplied by the gear ratio.
            For example:
            If the 1st gear ratio is 1: 1 , then the rear wheel torque is 1 X 470 = 470 lb ft
            If the 1st gear ratio is 5: 1 , then the rear wheel torque is 5 X 470 = 2,350 lb ft.
            If the 1st gear ratio is 10 : 1 , then the rear wheel torque is 10 X 470 = 4,700 lb ft.

            So the 1st gear has a high ratio, which means it is a very low gear with lots of grunt.
            The tranny is fast and looses no RPM and the other gears are spaced in the torque range.

            Then Jason talks about the implications of the percentage of total weight over the rear wheels, in favor of the ME
            The 2 cars weigh about the same , so total weight does not matter in this comparison.
            Jason cites the Motor Trend test that says the ZR! actually did 3.0. Jason verifies by comparison relying on the MT test of the ZR1.
            The tire!

            Seems that the C8 has more torque in 1st gear that the ZR1 after the raw torque is multiplied by the gearing, and has superior traction, and faster tranny. If not actually more torque then close enough to the Zr1 that when added to the traction and fast tranny it is as fast from a stand still.

            The deficiency of HP becomes a factor at high speeds the faster the car goes the more the C8 looses ground the greater Hp cars.

            It needs to be demonstrated that it is valid.
            Last edited by SheepDog; 07-25-2019, 09:19 AM.

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            • #7
              Originally posted by ZORA 69 View Post
              As precise as the figures are in the Videos math. I am surprised that a 40/60 weight front to rear ratio is used in the calculations when the real ratio is 41/59 front to rear ratio.


              He approximated the 40/60. And the 50/50

              The ZR1 is actually more like 52/48

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              • #8
                All C7’s are 50/50 except as SheepDog noted the ZR1. The ZR1 is 51/49.

                I love the fact that the C8 is 41/59!!! That is going to be one stat that creates much of its subsequently announced performance stats — already has for the under 3.0 seconds to 60 MPH.

                Another great video by Jason Fenske of Engineering Explained.
                Last edited by John; 07-25-2019, 12:51 PM.
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                • #9
                  Originally posted by JDMilw View Post
                  "...shifts in 100 milliseconds....."
                  Trying to wrap my brain about the super speed of that. Only way I come close is to say to myself that it is 1/10 of a second. I like that speed.
                  GBA Black; HTO Twilight/Tension interior; Z51 & Mag Ride; E60 lift; 5VM visible carbon fiber package; 5ZZ high wing; FA5 interior vis CF; ZZ3 engine appearance; 3LT; Q8T Spectra Gray Tridents; J6N Edge Red Calipers; SNG Edge Red Hashmarks; VQK Splash Guards; RCC Edge Red engine cover; VJR illuminated sill plates. Lifetime, annual contributors, and 23 year members of National Corvette Museum. Home is the beautiful Pacific Northwest.

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                  • #10
                    Lots of good points already, I'll just add that the C8 will have less driveline loss than the C7 and virtually no interuption of torque during upshifts. A Corvette engineer said that their 100hz test equipment could not even detect the DCT's shifts.

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                    • #11
                      495 hp? GM has understated power before
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                      • #12
                        Tjats one quick car. Cant wait to get my hands on one!

                        495 hp, 470 lb/ft of tq

                        dct shift speed of 100 milliseconds

                        41/59 weight distribution

                        sticky tires ...

                        under 3 seconds could be 2.95 seconds too and im ok with that...


                        dct s have tremendous consistency...

                        should be amazing to drive.

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                        • #13
                          Great job GM! The C7 Z06 A8 came out with a 2.95 0-60 in 2015 I suspect the 2019 is improved but not timed. So this C8 is quick for a base car. I'm expecting Mid 11's 1/4 as well!

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                          • #14
                            The've done such a GREAT job on weight distribution and weight loss over the years! I wish I could say the same! Thanks for the video!
                            NCM Life Member

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