heavychevy

This is true, if you watch the video of the lap at Road Atlanta Randy slows from 174 to 50 something starting from 300 feet. That is nasty levels of braking going downhill. On stickier tires he can go deeper. That's absurd. I think for sure the ZR1 outbrakes the Acr on the same rubber. So that's one weight related theory out the window. It can brake with the best of em. Even if maybe for just one lap. Lol.

johnglenntwo

https://www.motortrend.com/cars/chev...le-first-test/

Viper perfect FME - 49/51 WD

CW 3,480lb iron brake...

1. 2014 CHEVROLET CORVETTE STINGRAY CONVERTIBLE - 90 FEET

https://www.motortrend.com/news/20-b...nces-recorded/

THANK YOU 'Heavy', My Point!

heavychevy

Your point was that the aero was a primary factor in 60-0 braking distance being shorter. I told you aero does not do much under 80 Mph.

This proves My point.

johnglenntwo

Significant isn't primary! My verified point has been that less significant G-forces are still being meet with less significantly working aero, hence, your riding on rails enhancement.
I believe it's clearer now that the ACR's huge aero still has your unperceived effects based on the Real science of DF and drag.
The aforementioned Stingray data Really demonstrates the like.
I honestly don't know that they tested the convertibles brakes top down, but, the 14 feet came from somewhere. Twice the drag works!

heavychevy

Not at 60 miles per hour. It's still mostly mechanical grip, like I said. This is in just about every aero article around. You can find them. Drag helps, but not much at low speeds. Tires are the primary factor, then mechanical usage of the contact patch which is caused by the weight transfer place on the tires. Aero (including drag) is a far distant 4th place behind braking capacity.

Not to mention, this test only helpful to the extent that other cars were tested on the same/similar surface. Braking distances are greatly affected by the surface, heat in tires, etc. So you anecdotes are marginal at best.

johnglenntwo

That Marginal stunt is unexplainable by you, here!

Does the ACR still have 136lbs of DF at Tadges 50mph plus all its aero surface friction, and pressure, Drag. That's nothing!?
Isn't it true that 3,500 lbs of low inertia Corvette mass at 50mph isn't too exciting and a tad bit of DF with a similar kind of relative lift sure could feel like magic, and On Rails.

True enough about this though Heavy!
https://www.edmunds.com/car-reviews/track-tests/2014-chevrolet-corvette-stingray-z51-vs-2009-chevrolet-corvette-z51-track-test.html

Add DA...something else added in! Your tire explanation is an oversimplification, to me.

Dave Schotz

heavychevy

You weren't even talking about drag until I brought it up and explained it to you. It is an oversimplification, but frankly I'm not willing to add in contact patch shapes, cog etc as factors as it's hard enough as is to understand exactly what you are trying to say.

I stand by my point, Aero does not have a big effect under 80 or so mph.. The forces created by the weight of the car itself are far greater. Period.

johnglenntwo

I new I could roll yah! "I'm Kidding!"
But, Drag was brought up by Me.
And the CoG's effect on how the weight moves around on the tire patches. IE The diagonal path a front engine weight can travel to the opposite side rear wheel. And the heavy SC effect and MR compensation lying herein.
And that relationship between a tall tires better cornering and a wider tires straight line traction. That tire patch rectangular shape, me not understanding is it!?

The car weight was even a given by MT!
The ACR just shattered our braking record, stopping from 60 mph in a neck-snapping 87 feet. Why? The big carbon Brembos help, but so do the ultra-sticky Kumhos, as well as all that fancy aero.

heavychevy

Magazines know less about it than your average track rat. You act like they are professional racers or something. Is that your method of validation? Lol. Any decent pro race outfit will tell you arent going to gain much at all from aero on low speed tracks. And that's over a whole lap. 60-0 is miniscule even compared to that. I have a grand-am winning shop that takes care of my car. I've been doing this for 13 years, lap after lap after lap. Question after question after question. Grand am/imsa/world challenge winners coaching and driving with me. This isn't conjecture or guessing, and I have far more data on the same car over the years from street to track only than magazines that have cars for a day or two.

Take all the aero off the same Acr on the same day, same surface and 60-0 may not change at all. I bet it doesn't.

The single biggest mod you can do for your car is tires. Period. The contact patch is everything as it is where the rubber meets the road. Everything else is contingent on that. Wider is not always better for braking as the shape of the contact patch changes with wider tires and can affect braking negatively.

Not to mention, this is far to short of a test wiyh far too much room for discrepancy to compare different tests. 60.1 mph vs 60.9 is different. How you apply the brake is as important as anything. You have to maximize each brake system by not engaging abs. That would take lots of tests to make sure you got the absolute best from each one. Making sure tire temps are just right, same conditions from one day to the next etc. Too much room for user error and variability. The magazine results are marginally scientific at best.

You can believe it or not, put all the aero on your car you can and go buy a Vbox and show us, same day, same car, with Pyrometer tests and I'll believe you, but otherwise, this is a dead debate.

johnglenntwo

1. The Viper's record 87' vs 93'; tire, brakes, and aero
2. The ZR1's 88' vs 90'
3. The Z51 convertibles 90' vs 93'

http://fastestlaps.com/lists/top-qui...stoppers-60mph

Data doesn't have to be perfect just relatively compiled for assumptions to be reasonable.
Welcome to the world of Magazine Racing, again, mutual exclusivity duly noted.

(Magazine found appreciation of the Viper.
Heads and cam to compensate its extra drag more, and front tire options - that's it. Yes, MPG - forget about it.)

DebRedZR1

Exactly why most of us make use of the IGNORE feature and don't feed the trolls.

DebRedZR1

Let me make this VERY clear, any continued NONSENSE posts, deleting numerous posts, etc are going to start resulting in some actions being taken. End of warnings.........

Snorman

For the life of me I don't understand why you just don't ban him.
S.

RapidC84B

I'd take the Viper.... NA, less weight, KISS.

TrackAire

Well, my beloved Viper is no longer the King of Willow Springs......the ACR-E record has fallen:

https://www.motortrend.com/cars/pors...8B60284FFE2C3D

RapidC84B

For $300K or whatever it costs it had better well shatter some records.

TrackAire

I agree with you.....but there is something to be said about a $300k plus car that you can sell for more than you bought it for a couple of years down the line.

Regardless of what car is faster or the cost, this really is a good time to be a gear head and petrol lover. If you had told me in 1981 that we'd have stock vehicles available with over 600 hp I would have never believed it back then. I was just happy to be driving a 1978 Trans Am with a smogged up 403 Oldsmobile motor putting out a throbbing 180 hp.

Sub Driver

Can you please stop posting random links without any context? Remember, only you can hear the multiple voices in your head.

DebRed, didn't you say something earlier about nonsense posts?

johnglenntwo

Maybe the Viper contingency can help fill in the blanks!?