Traction? What's that?
 

Sorry I asked....

Nothing is amiss, and I am not sure why it took you an entire book and arbitrary pictures to explain a simple condition. Here is a tip, if you want help with something limit your question to a few lines as no one is reading all that crap you wrote. Further, you are way over thinking this, and clearly have no experience in this area. So stop trying to use physics that you don't understand in your search for such a simple answer. I have a competition racing license, am a racing instructor and study these things literally every day, and not even I would spend more than 5 seconds on this topic. You simply went to 3rd gear too early. This causes a shock to the rear (where power is delivered) as the engine must spool back up very rapidly to reach the speed of the driveline and the tires, which in turn causes a violent shock to the driveline/tires and loss of traction. The solution is to either slow down more before you go to third gear, or blip the throttle prior to entering third gear. By blipping the throttle you can better match the revs of the engine to the speed you are at and avoid this shock to the driveline and tires.

With what you did, the rear WILL lose traction. One tire will lose traction first, due to a wide variety of reasons (road surface irregularities, crown of the road, weight distribution of the chassis, the direction of torque of the engine, small and minute variations in mechanical grip of each tire etc etc) and cause the car to step-out in one direction.

So, stop shifting to third so early, or learn how to rev match. The End. Nice car though. I suggest you take your road racing escapades to your local circle track or road course. You will learn (with an instructor in the car with you) how to control the car when driven in anger. You will "un-learn" all of these bad habits and be better for it. Good luck.

I braved the read, needed to rev-match or use the brakes more instead of probably almost over-revving the engine to slow down. +1 on track experience and you will learn the importance of what Mordeth explained and what I just said.

Cliffs: Suspension fine, do not over-rev engine.

Its apparent almost anyone can own a z06...but maybe not everyone should.

Peace

Not sure about the mods, but my R888R's same size as stock, are incredible.

From a roll around 5 mph, they will break lose for about the first 10 feet... but barely... then it's gone. It won't spin anywhere else, at any rpm, in any gear.

However, the dump to third gear at a very high RPM as you did, having tires that don't get traction could have saved your drivetrain if it spun... Not sure you want better traction if you're dumping it into third gear at upwards of 170... I likely could have read your post wrong, I'm also trying to save my kids from killing each other right now over some legos. So I apologize if I missed something.

This thread delivers

Shock loading a dynamic system is never a good idea...especially when slowing down.


https://cimg6.ibsrv.net/gimg/www.cor...48b8d67439.png

Horseshit. If you hadn't deleted your rambling post then this horseshit would be more evident - although I don't blame you, considering the content. And all of my advice was sage advice, considering what you wrote, what you claimed you did and how you incorrectly interpreted it all.

So let's again, get to the point:

1) Don't over-rev your car and shock the suspension and tires.
2) Don't use the engine to brake, especially from those speeds. It is dangerous and stupid, especially for an untrained driver like yourself. That's what the brakes are for.
3) Learn how to rev match when appropriate.
4) Seek out proper training on how to operate your vehicle in a high speed environment. Road racing at 170mph on public streets is not only dangerous, but extremely stupid considering your glaring inability to control the car and lack of training on the proper inputs to achieve the desired effect. These proper inputs are learned behaviors, and so you must study them and train for them.

Additionally, it was the car's nannies that saved you (not your slow reaction to events, which were self induced). So you should be grateful for them, as they saved your life (assuming your initial rambling and now deleted post was even true).

And finally, if you are a physicist, then you understand the importance of using accurate data when performing calculations. Your data and assumptions are wrong (not surprising). The coefficient of drag for a C6Z, as published by the manufacturer is .34. The frontal area of a C6Z is 22.3 sq ft. I am surprised at your glaring lack of accuracy, especially when preciseness is critical when considering the nature of fluid dynamics.

The proper equation for drag is as follows: D = Cd * A * .5 * r * V^2. Whereby D = drag, Cd = Coefficient of drag, A = the reference area, r = density and V = velocity. Typed out by me and taken directly from page 47 of the book I have in front of me titled: "Race Car Aerodynamics: Designing for Speed (Engineering and Performance) by Joseph Katz (as a reference and citation).

So when we plug this example into the proper equation in meters using the correct assumptions we have D = .34 * 2.071738 * .5 * 1.22 * 75.9968^2 = 2481.6138006 N

And get better tires.

*mic drop*

I mean, if you are going to boast about yourself, you should put enough effort to, at least, state accurate figures.

Anthony at his best in APA format... The initial post needed a Thesis.

I did not see the unedited first post, but advice to the OP (and to the rest of the posters - who I value). Don't let this thread prevent you from participating in the forum. All of us have our areas of expertise outside the forum. Don't try to impress with high level technical stuff unless it is absolutely necessary to answer the question.

The answers addressing tires, when to downshift (less than 122 MPH into 3rd) and rev matching are the solutions to the problem I think was asked.

this thread makes me think i should have applied myself more in school...

I'm with you on that one. I though all you had to do was mash the gas, shift, turn the steering wheel and hit the brakes.

The initial post was a joke, or so it seemed.

Mordeth was spot on. I didn't feel like wasting time responding when he summed it up so well.

This is LMM worthy.

wait .....thats not what you do????
God Ive been doing it wrong

Clif