C7Z vs Viper dyno
12-29-2014, 09:05 PM
#61
Instructor
As always, great job Tony. Thanks for putting this together. Maybe I missed it in the photos, but did you log the AFR on any of the pulls? Just curious to see if the Z's AFR is as fat as the Vipers.
12-29-2014, 09:15 PM
#62
Race Director
Okay, I'm dusting off my old blog page that I put together. I'd like to keep these comparisons more magazine-esque, like when I used to write for them. They get lost on forums.
Link to info here: http://nineballgarage.wordpress.com/...2014-viper-ta/
Tony
Link to info here: http://nineballgarage.wordpress.com/...2014-viper-ta/
Tony
Thanks!
12-29-2014, 09:24 PM
#65
Le Mans Master
Either way, nspec won that race - since both cars are his. Haha
Appreciate what you are doing for those who care
It does matter here
On a side note, but only if you are open for it?
Your username "nineball" has my attention, and makes me wonder how you earned your name?
Are you a rack runner? I was, and used to wake up in the middle of the night saying, "nine ball in the side pocket". On a fluke I made ESPN, but that has nothing to do with how I earned my name
What about you?
12-29-2014, 09:30 PM
#69
Thanks for setting it up Tony. It was good to see the consistency in the dyno numbers.
BTW, my first race with my own Z06 went just like it did with Tony the first time we went at it. 2-3, dead on, 4th the viper pulls. Didnt get a chance to race them any more.
BTW, my first race with my own Z06 went just like it did with Tony the first time we went at it. 2-3, dead on, 4th the viper pulls. Didnt get a chance to race them any more.
12-29-2014, 09:31 PM
#70
Le Mans Master
a full second ahead at the 150-mph mark.
http://www.caranddriver.com/comparis...tte-zr1-page-3
Without all the freaking aero!
http://www.caranddriver.com/comparis...tte-zr1-page-3
Without all the freaking aero!
12-29-2014, 09:35 PM
#71
Racer
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Good to know the Viper won again. I was happy to hear that considering your Viper is wearing the heaviest factory wheel in the lineup. Those big chrome 5 spokes are a total of 40lbs heavier than the Sidewinder 2's on the TA's.
12-29-2014, 09:35 PM
#72
Racer
Member Since: Mar 2008
Location: The Republic of Texas
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If anyone around Houston is bored, I'll be taking my '14 Viper to KPRacing.com at 11:30 or so, to get baseline dynos done. If I have a factory freak, you are invited to come discover this with me.
A good friend dyno'd his C7Z there last week, so I will update the thread with some dyno comparisons.
C7Z vs Viper - max numbers
C7Z vs Viper - both hot
'13 Viper vs '14 Viper (I dynoed my '13 there, a year ago, stock)
And, if anyone with a stock C7Z wants to have some fun at lunch, we can do that too
EDIT 7:30PM I posted the results and write-up on my blog page. I will try out this blog stuff, because testing seems to get lost on forum threads.
http://nineballgarage.wordpress.com/...2014-viper-ta/
A good friend dyno'd his C7Z there last week, so I will update the thread with some dyno comparisons.
C7Z vs Viper - max numbers
C7Z vs Viper - both hot
'13 Viper vs '14 Viper (I dynoed my '13 there, a year ago, stock)
And, if anyone with a stock C7Z wants to have some fun at lunch, we can do that too
EDIT 7:30PM I posted the results and write-up on my blog page. I will try out this blog stuff, because testing seems to get lost on forum threads.
http://nineballgarage.wordpress.com/...2014-viper-ta/
Tony-
Admittedly, I am responding to the first post, having read none of the ones in between-yet. Regardless, this is a great write up. You have taken a great deal of crap from many on this forum over the past few weeks...most likely, undeservedly. That said, you really seem to be a guy who is after the truth. I appreciate what you have done to try and get to the bottom of the comparo. I will now go back and read every post. Happy New Year!
12-29-2014, 09:49 PM
#73
Your statement to the effect that what matters for straight line acceleration is how much parasitic drag a car produces (as you express it, C/D x frontal area) is generally correct BECAUSE the vast majority of drag and roll races do not involve cars producing sufficient downforce relative to the hp they are producing to significantly affect the outcome - mainly because of their low downforce shapes, but not infrequently because they don't get going fast enough.
HOWEVER, any time a car produces downforce it absolutely produces drag. A car that generates downforce sufficient to meaningfully raise the speeds at which it corners on the track (for our purposes, roughly 70 - 150 mph) will absolutely accelerate more slowly than an otherwise identical car that does not generate any useful downforce. This is the fundamental L/D metric by which any lift generating shape is measured. It also gives rise to any such shape's "drag polar" - which is a plot of how much drag it produces for how much lift (downforce) it produces. That plot looks like a horizontal parabola.
The C7Z Z07 is designed to generate useful downforce. Above say 70-ish mph (100 ft/sec) it's downforce induced drag is far more than its parasitic drag. The faster it goes, the more horsepower it will use overcoming the downforce induced drag. It will make a very noticeable difference.
Speaking of sporty, Flyboy22's ride has an L/D of almost 8.5 -- not bad for a supersonic stunt plane.
12-29-2014, 09:58 PM
#74
Sorry, but this is a little misleading, and Flyboy22 is exactly correct.
Your statement to the effect that what matters for straight line acceleration is how much parasitic drag a car produces (as you express it, C/D x frontal area) is generally correct BECAUSE the vast majority of drag and roll races do not involve cars producing sufficient downforce relative to the hp they are producing to significantly affect the outcome - mainly because of their low downforce shapes, but not infrequently because they don't get going fast enough.
HOWEVER, any time a car produces downforce it absolutely produces drag. A car that generates downforce sufficient to meaningfully raise the speeds at which it corners on the track (for our purposes, roughly 70 - 150 mph) will absolutely accelerate more slowly than an otherwise identical car that does not generate any useful downforce. This is the fundamental L/D metric by which any lift generating shape is measured. It also gives rise to any such shape's "drag polar" - which is a plot of how much drag it produces for how much lift (downforce) it produces. That plot looks like a horizontal parabola.
The C7Z Z07 is designed to generate useful downforce. Above say 70-ish mph (100 ft/sec) it's downforce induced drag is far more than its parasitic drag. The faster it goes, the more horsepower it will use overcoming the downforce induced drag. It will make a very noticeable difference.
Speaking of sporty, Flyboy22's ride has an L/D of almost 8.5 -- not bad for a supersonic stunt plane.
Your statement to the effect that what matters for straight line acceleration is how much parasitic drag a car produces (as you express it, C/D x frontal area) is generally correct BECAUSE the vast majority of drag and roll races do not involve cars producing sufficient downforce relative to the hp they are producing to significantly affect the outcome - mainly because of their low downforce shapes, but not infrequently because they don't get going fast enough.
HOWEVER, any time a car produces downforce it absolutely produces drag. A car that generates downforce sufficient to meaningfully raise the speeds at which it corners on the track (for our purposes, roughly 70 - 150 mph) will absolutely accelerate more slowly than an otherwise identical car that does not generate any useful downforce. This is the fundamental L/D metric by which any lift generating shape is measured. It also gives rise to any such shape's "drag polar" - which is a plot of how much drag it produces for how much lift (downforce) it produces. That plot looks like a horizontal parabola.
The C7Z Z07 is designed to generate useful downforce. Above say 70-ish mph (100 ft/sec) it's downforce induced drag is far more than its parasitic drag. The faster it goes, the more horsepower it will use overcoming the downforce induced drag. It will make a very noticeable difference.
Speaking of sporty, Flyboy22's ride has an L/D of almost 8.5 -- not bad for a supersonic stunt plane.
Last edited by Divexxtreme; 12-29-2014 at 10:14 PM.
12-29-2014, 10:15 PM
#75
Instructor
Well, at least I now know why the shop said there was no chance of my ZR1 getting on the dyno today for tuning, and finished up.....
Thank you for gathering all the data on these cars. It has been interesting to follow and I still hope to catch a track day with you guys once my car is buttoned up.
Thank you for gathering all the data on these cars. It has been interesting to follow and I still hope to catch a track day with you guys once my car is buttoned up.
12-29-2014, 10:36 PM
#77
Drifting
Thank you for the dedicated efforts (exhaustive, I'm sure!) to detail objective information and data to help and support fellow auto enthusiasts in the enjoyment of our shared passion.
FANTASTIC, and again THANK YOU!
12-29-2014, 11:05 PM
#78
Drifting
Expected. All the other posts thank Tony for his time and effort, but yours always seem to have an ulterior motive. Why don't you take your shtick to the other forums?
12-29-2014, 11:32 PM
#79
Drifting
Awesome job Tony! You've taken a lot of crap on this site for posting the facts as you've seen them without any sugar coating. Thanks for all the hardworking and coin spent on your part!!!
12-29-2014, 11:38 PM
#80
I'm really surprised that anyone here is surprised by any of this - like it's new information. The outcome is still the same... The C7Z makes the advertised power but still gets molested by the Viper.
Just appreciate the C7Z for what it is.. It's a great value mid-tier sports car that isn't the fastest in it's price range (like it use to be). Appreciate it for what it is.
Just appreciate the C7Z for what it is.. It's a great value mid-tier sports car that isn't the fastest in it's price range (like it use to be). Appreciate it for what it is.
Last edited by EdwardETraylorIII; 12-30-2014 at 08:25 AM.