Notch

I'm not reinforcing any of your points.

1analguy

That's probably because putting lighter, better-performing, smaller wheels on the car won't make the car "look" better. Not even the fact that the smaller and cheaper wheels would thus doubly improve the much-ballyhooed performance-per-dollar advantage of the Corvette that everyone here stakes their personal worth on appears to be enough to over-ride the need to "look good". Ah, the costs of vanity...



Not here. Not from what I read on this forum. The universe only exists for the Corvette to generate the lowest lap times ever recorded by man. They don't care if the car is loud inside, or rides rough, or corners much less capably on the less-than-perfect roads in the real world, as long as it generates those lower lap times on a smooth race track. And if you don't feel that way, then what the hell is wrong with you?



Funny you should mention this. Porsche has a tendency to use a larger percentage of actual switches and buttons to control those functions (something I laud them for) than most other manufacturers...and magazine testers usually berate them for doing so. Apparently, they would rather build cars for buyers than for testers.

I agree that it is unlikely. If they did offer a DCT, the option would have to cost thousands of dollars, which would slash quite heavily into the performance-per-dollar factor that the car enjoys right now, all for only a relatively small improvement in the car's performance. "Relatively" small, in comparison to the very noticeable improvement that it does make in a car with a smaller, more highly-stressed engine...such as a Porsche.



Well, GM is pretty good at reducing the cost of some of these exotic options. The option package offered on the Z06 which included CC brakes cost around $1000 less than what Porsche charges just for the brakes alone, so who knows...



Like we weren't waiting for that. Thank you, Ashley Force...



Caroll Shelby's guys did it in an old garage. It made for a lot of race track wins, but which car was a better road car...Cobra or Corvette?



Let's compare apples to apples. Go back and dig up the original 'Ring time for the Z06. You know, the time that it posted after its first run on performance street tires...not the time it posted on its second appearance (on D.O.T./track tires). I believe the GT3 ran on performance street tires. Please correct me if I'm wrong...it has happened on occasion.

JerriVette

I'm a huge fan of the new c7 and understand that a DCT is not available. I'm surprised the DCT guys on this forum are not announcing in full glory the drag times quoted by the magazines today at 12.2 @ 117 mph instead of the 3.8 (3.9) and 12.0 @ 119 mph as stated by gm...

Quite honestly that differential is because human error is being taken into account and that my DCT friends is why DCT is so cool...

Im sure with more time behind the wheel the automotive press will eventually bring down the times but with DCT transmissions that's not necessary..

Just thought I'd post up something that quite a few of you guys who can't live without DCT might enjoy reading.

For the. Guys who love manuals....I'm sure within a month you would be accustomed to the vehicle to tear off 3.8 second runs to 60 mph and many will eventually get a stock car into the high 11 s at 120 mph.

Guibo

Do you have any proof of this? My understanding is that Sport Auto only supertests vehicles that have been federalized to German/EU standards. As an example, look at the SRT-10 that was supertested:

Notice the rear-exit exhausts. This is one many changes required for the car to be road legal (in this case for drive-by noise regs) in EU/Germany and thus representative of a car that is available to the German market. Notice there hasn't been a supertest of any ACR, which as far as I know is only available as a private import vehicle, with few (if any?) of the detail changes required for the EU.

As a practical matter, I doubt Sport Auto has so much revenue that they can buy $100k GT-Rs and fly them over to Germany from the States. That would be borderline retarded considering GT-Rs are sold in Germany, nevermind neighboring countries like Austria, Switzerland, France, etc.
Nor are they likely to be buying 100k euro Porsches. The supertested Porsches almost invariably carry the same exact plates reserved for the press cars provided by Porsche for early test drive impressions.
If, as you say, Sport Auto bought a 991 S off of a dealer lot to "stop shenanigans," then that has backfired: The supertested 991S lapped in 7:44 after only 2 flying laps. Pretty much bang-on dead with Porsche's initial claim of 7:40. And that hasn't stopped Porsche from releasing lap times for its test cars at all.

And as 02HREBlue suggested, Porsche doesn't have to sell the new GT3 only to old GT3 customers, some of whom might have even opted for the DCT were it available on the 997.

Maybe some of the "DCT guys" realize the variances due to surfaces and hardly broken-in engines are at play here, and not the role of DCT.

Guibo

But F1 weight distribution has been regulated as such since Pirelli became the tire supplier. Though that's not to say the F1 teams wouldn't strive for more rearward bias if there were no rules in place. R&T's test of the Jaguar F1 car suggested a figure as extreme as 42/58. Which is closer to the 991's 38/62 than it is to 50/50. The Corvette engineering team tried to get the rearward weight bias of the Le Mans racing Corvette. Not 50/50.

All else being equal, couldn't a longer wheelbase increase stability and ride bumps better? An added benefit could be distributing more weight rearward.
That's another variable you haven't accounted for in why the Corvette seems as fast as it is: Its wheelbase is some 10 inches longer than the 991's. So in addition to more power, fatter rubber (in GS and C6Zs), having an engine located where it should produce less on-throttle understeer and less drop-throttle oversteer, you have a chassis that should be inherently more stable.
The Cayman R's wheelbase was nearly 5 inches longer than the old GT3's, so it's not yet quite a pure test of engine placement (though I agree a similarly tuned Cayman should handle better).

SCM_Crash

We'll see... I've taken a few cars to the track with no prior seat time and ran the quoted manufacturer times (or faster). And I've never been to a sea-level track.

RedLS6

I was referring to second moment of area - when it's integrated about a line or plane, it's as you say, and when it's integrated about a point in a circle, it becomes a polar moment. In any event, sorry about the terminology as I had second moment on my mind from an unrelated problem.

A lot of it depends on the vertical distance between the CG and the plane which contains the normal forces on the tires at the tire/road interface.

I agree with you on the Corvette weight distribution, to a point. In an ideal world, if we wanted to maximize tire loading for flat corners with no acceleration, we'd locate the CG vertically in the plane along the bottom of the tires. I'm not considering any second-order effects here for simplicity. As the car rotates around the corner, this arrangement maintains weight distribution, since there is no longer a CG-related moment about the longitudinal axis loading the outside tires and unloading the inside tires.

We'd also put this imaginary CG in the middle, to lower polar moment to a minimum, while we're at it.

We can't do this, but Corvette does the next best thing by keeping the engine, diff, and trans as low as possible, along with the rest of the car, minimizing the loading/unloading couple. The way the components are distributed on the chassis ensures a good weight distribution and maximal tire loads, and the vertical CG location helps to ensure that these tire loads deviate as little as possible from ideal by minimizing the couples around the Corvette's longitudinal axis.

In a flat, constant velocity corner this works well. It is actually easy to unload the tires on the Corvette, though. Trail-brake a C5 or C6, and you'll unload the inside rear tire dramatically near the edge on a stock vehicle. Vertical CG along with braking+cornering inertial forces. I don't autoX anymore, but I do road race about once per month. My ABS controller died on the track a couple of years ago, and I ran the weekend with no ABS and no stability control. I was surprised at just how much the inside rear is unloaded here, as the wheel lockup let me know. This brings about another point; the electronics tremendously helps to manage stability during these dynamic tire unloading conditions.

I agree with you on the constant-radius, increasing speed turn. The Vette is stable here with a little throttle, and is manageable with a lot of throttle, since the rear picks up weight but the fronts still have a good plant. I'd think a rear-biased Porsche would operate here with a slightly higher slip angle in the front.

The rotational force is greater on the Vette, but so is the polar moment as compared to the Cayman. I don't know which is greater, so I couldn't definitely say that Corvette has an advantage over the Cayman here in terms of rotational acceleration. Maybe it does. When we start talking about chassis flex, we open up a whole new can of worms. That's all for now. \



.

Shaka

Amusing thread. At least everybody is a car nut. We should all have a few beers together. Imagine the poor behaviour that would ensue. I don't have the time to kick every dog that barks, like ' dynamic weight distribution'. WTF does that mean.
I don't understand what, 'Seems as fast as it is" means either.
It is accepted in front engined sports car design that there should be a rearwould weight bias of 48 front 52 back and by lengthening the wheel base on the C7, they achieved that. Just can't make a stiff chassis that long, at least a light one anyway. The high performance Vette will surely have a fixed roof again. It's amazing how many duties the Vette must perform. Two fat dudes with their golf clubs being one. No other manufacturer will go in that direction. First thing I'm going to do is jack the car up on the designated mount points to see if the door gaps open.
I love Porsche, Ferraris, Vipers, etc. They all have their distinctive characters. I drove one of those Suburu BRZs which shares the same platform with the Toyota 86 and the Scion FRS. Flat low CG engine, long wheel base 48 52 and as tight as a nun's...Why does a Cayman cost so much? A loaded Cayman should be $50gs tops and a F458 should be $150gs tops. PT Barnum would be a Porsche dealer if he were alive today.
Vettes value is tops, but then there is the Suburu.

For car nuts.

Racer X

Perhaps it is to accomodate the 42MM longer 7 speed. The wheelbase is 25MM longer. Or maybe high speed stability?

JoesC5

But....that was an obsolete, pathetic C6 Z06 in the video....not a ZR1.

Guibo

Haven't yet sat in the BRZ/FRS, but have seen them up close. Quality of materials, stitching, etc, don't appear to be as good as the Cayman's. As to why Porsches and Ferraris cost that much, the reason is simple: Because people continue to pay those prices. When people refuse, then the prices will go down. Simple supply and demand. As a business, Ferrari would be stupid to leave $100k on the table that it could easily otherwise toss into its coffers. It might surprise you that there are people optioning up their Boxsters into $100k territory, and it's not hard to find 458s with over $50k just in options (about as much as a whole C7). There's more to a sports car than just 10/10ths on-track measurements. Toyota/Subaru realize this. So does GM with the C7.

Dynamic suggests it is the distribution that matters when the car is in motion and experiencing load changes, rather than purely steady-state cornering. How a car gets into and out of a turn can be just as important.
I was referencing posts that seem to be in awe of the Corvette's track numbers, such as:

There's a lot more to it than just the engine placement, and lap times are not always just about handling prowess, though on a fast track like the 'Ring, a longer wheelbase helps. This is not something that the Porsche has. (Nor the power. Nor the torque. Nor the tire sizes.)

First pint's on you.

02HREBlue

Im not a crappy winner. Lets agree to wait for official times hopefully on street tires. We have a while, likely next spring we can renew the thread! I hope BOTH go that fast so we can be even.

dcbingaman

Agreed. Let's stay in touch.

BTW, my Dad's whole family is from Des Moines, IA. My Grandpa moved him to Davenport, and then onto St. Louis, where he met Mom. There are a lot of Bingaman's buried in Iowa....God's country, for sure. My only connection there now is part ownership of a Kum and Go gas station in Des Moines.

Thanks again, Don Bingaman

02HREBlue

Agreed! Small world because the personal pilot for owner Krause at Kum and Go is my next door neighbor!

God's country-----thats the best one I have heard yet! No wonder you moved away.

Which store do you part own? I stop there all the time. Good gas.