280 MPH corvette
Originally Posted by mazspeed
The Hennessey Viper is not going to come close to 255mph. They have never tested it to my knowledge and all this "clamed" top speed is silly. And no, a stock corvette will not see 280. Tell your buddy to stop drinking. 
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From: Anna, OH
Originally Posted by chicane
And what gives you this impression ??
The guy with "the news" might just be talking about the Blue Devil. It is slated as production coupe, with a better DC than the the Sledgehammer, its 775 pounds lighter and makes more power..... with a supercharged LS9.
Mile an hour is more related to DC than horsepower. Hell, there were cars in the late 60's did more than 250, with half the tire, less aero and suspension designs of 40 years ago. Albeit being a race car, it was possible then.... and its more than possible now.
The guy with "the news" might just be talking about the Blue Devil. It is slated as production coupe, with a better DC than the the Sledgehammer, its 775 pounds lighter and makes more power..... with a supercharged LS9.
Mile an hour is more related to DC than horsepower. Hell, there were cars in the late 60's did more than 250, with half the tire, less aero and suspension designs of 40 years ago. Albeit being a race car, it was possible then.... and its more than possible now.
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From: Anna, OH
Originally Posted by Big-DEN
HOS =fast would force go if he had a 4 mile straightway and a 4 miles to slow down on?
Those cars don't reach top speed in the 1/4 just like yours and mine dont.
Those cars don't reach top speed in the 1/4 just like yours and mine dont.
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Originally Posted by LTSpeed
You have no idea what you're talking about. The C6 Cd (Drag Coefficient) is way higher than the C4 or C5, mainly due to the necessary downforce improvements on the nose and tail.
The C4 Drag Coefficient is 0.34.
The C5 Drag Coefficient is 0.29.
The C6 Drag Coefficient is 0.29. Which is the second lowest of ANY performance production car in the world.
Originally Posted by LTSpeed
Even if the Blue Devil has 1000hp machine off the showroom floor, there's no reason for GM to make it go 280mph. It could not even be driven safely between stoplights. It wouldn't even be safe at the strip!
And FWIW. I worked for the private company that developed, engineered and produced the suspension components and drivetrain for the Sledgehammer, right along with a few other supercar Corvette's. Not to mention that our engine builder was the very same, that ran Reeve's engine development program a few years later.... and I do have knowledge of what is being discussed, specifically the car in question.
So, I guess you could say that I might know something.
Last edited by chicane; Aug 10, 2006 at 10:17 PM.
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From: Anna, OH
Originally Posted by chicane
The C4 Drag Coefficient is 0.34.
The C5 Drag Coefficient is 0.29.
The C6 Drag Coefficient is 0.29.
Just unlike the other 1000bhp cars running around right ??
The C5 Drag Coefficient is 0.29.
The C6 Drag Coefficient is 0.29.
Just unlike the other 1000bhp cars running around right ??
http://www.answers.com/topic/drag-coefficient-1
You've got your numbers flipped. The C6 (0.33) has much more downforce; hence the higher drag. The Z06 (0.34) is a little worse due to the nose intake and wider stance. Does that make the C6 slower? No way. In fact, it's what allows it to put 505hp to the road at 198mph without add-on bodywork.
Props on your work experience with the Sledgehammer people.
I guess if you're talking about turbo (or SC) cars, then 1000bhp is safe light-to-light. But an NA 1000bhp car is a nightmare. If Blue Devil is SC, it's unlikely to have 1000hp--unless the hood is 6" higher for a roots blower. The LS7 barely fits now! I guess it's all speculation anyway at this point. GM is doing some SC work lately, but no turbos that I know of...
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Well, it seems that there is a little confusion to what is published by some. And "answers.com"..... has it wrong.
I got my information and specifications from Jerry Palmer, the actual GM designer of the C4 body style.... it remains, as stated, 0.34. The reason I came into this knowledge was the end results of Reeve's team doing a body kit for the Sledgehammer and in its efforts to re-direct and clean up the stock/factory C4 body.
And this link specifically from the General Motors design group, it clearly states that in 1997 the C5's Cd at 0.29.
I will also quote Jerry with this, from an article in "Corvette Illistrated":
"The coefficient of drag was .33 for the ‘98 Roadster and .29 for the ‘98 Coupe. Considering that the coefficient of drag for the ’84 Corvette Coupe was .34"
Hell, for that much, just Google it....... NDA's or not, your sources are are in left field.
I got my information and specifications from Jerry Palmer, the actual GM designer of the C4 body style.... it remains, as stated, 0.34. The reason I came into this knowledge was the end results of Reeve's team doing a body kit for the Sledgehammer and in its efforts to re-direct and clean up the stock/factory C4 body.
And this link specifically from the General Motors design group, it clearly states that in 1997 the C5's Cd at 0.29.
I will also quote Jerry with this, from an article in "Corvette Illistrated":
"The coefficient of drag was .33 for the ‘98 Roadster and .29 for the ‘98 Coupe. Considering that the coefficient of drag for the ’84 Corvette Coupe was .34"
Hell, for that much, just Google it....... NDA's or not, your sources are are in left field.
Last edited by chicane; Aug 7, 2006 at 11:56 PM. Reason: Spelling
Launching!
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From: Exton, Pennsylvania
Originally Posted by LTSpeed
l]
You've got your numbers flipped. The C6 (0.33) has much more downforce; hence the higher drag. The Z06 (0.34) is a little worse due to the nose intake and wider stance. Does that make the C6 slower? No way. In fact, it's what allows it to put 505hp to the road at 198mph without add-on bodywork.
You've got your numbers flipped. The C6 (0.33) has much more downforce; hence the higher drag. The Z06 (0.34) is a little worse due to the nose intake and wider stance. Does that make the C6 slower? No way. In fact, it's what allows it to put 505hp to the road at 198mph without add-on bodywork.
How does the LS7 "barely fit" into the Vette? It is almost the exact same dimensions as an LS2.
About your 1000hp NA being a nightmare comment. I largely agree with you on that, except GM did build the Cadillac Sixteen cocept with a 13.6L 1000hp engine that held a very smooth idle, according to any automotive press people that have driven it. Numbers like that can be done naturally aspirated, it just takes displacement.
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From: Anna, OH
Originally Posted by RussStang
No dude, you have your numbers wrong....<snip>
How does the LS7 "barely fit" into the Vette? It is almost the exact same dimensions as an LS2.
How does the LS7 "barely fit" into the Vette? It is almost the exact same dimensions as an LS2.
Question: What aero changes make the C6 and Z06 different in terms of downforce? Answer: None.
The Z06's wider stance adds to overall drag (flat plate area) but is barely significant in terms of Cd. The only big difference in Cd between the C6 and Z06 is from the super-wide tires. All I can say is that my data shows them nearly identical at 0.323-0.336 with identical tires--depending on speed and suspension setup. I don't care what any magazine says when I have my own data. (BTW, I think we agree on the C5=0.29. On the C4 I don't know first hand.)
The original premise of this discussion was that Cd is more important than power for top speed. I'm only trying to point out that no 'vette is going to go 280mph at any Cd with only 1000hp. Even at 1350lb, Honda's F1 car (totally trimmed out to 0.18 Cd) with 850hp only hit 248mph last month in Bonneville.
Originally Posted by LTSpeed
The Sledgehammer 'vette went 254mph on a 7-mile oval. Street Car--NOT!!
I have seen video of these being driven on the street.
A 100% legitimate street car from all the information I have seen.
to OP: 280 is a bit much to ask from ANY production car. We might possibly see 210-215 if the power is there.
Originally Posted by LTSpeed
The LS2 barely clears the hood as well. A roots blower--likely needed to get an LS7 to 1000hp--would not clear. A turbo setup would be have to be pretty wild to fit under there too.
Question: What aero changes make the C6 and Z06 different in terms of downforce? Answer: None.
The Z06's wider stance adds to overall drag (flat plate area) but is barely significant in terms of Cd. The only big difference in Cd between the C6 and Z06 is from the super-wide tires. All I can say is that my data shows them nearly identical at 0.323-0.336 with identical tires--depending on speed and suspension setup. I don't care what any magazine says when I have my own data. (BTW, I think we agree on the C5=0.29. On the C4 I don't know first hand.)
The original premise of this discussion was that Cd is more important than power for top speed. I'm only trying to point out that no 'vette is going to go 280mph at any Cd with only 1000hp. Even at 1350lb, Honda's F1 car (totally trimmed out to 0.18 Cd) with 850hp only hit 248mph last month in Bonneville.
Question: What aero changes make the C6 and Z06 different in terms of downforce? Answer: None.
The Z06's wider stance adds to overall drag (flat plate area) but is barely significant in terms of Cd. The only big difference in Cd between the C6 and Z06 is from the super-wide tires. All I can say is that my data shows them nearly identical at 0.323-0.336 with identical tires--depending on speed and suspension setup. I don't care what any magazine says when I have my own data. (BTW, I think we agree on the C5=0.29. On the C4 I don't know first hand.)
The original premise of this discussion was that Cd is more important than power for top speed. I'm only trying to point out that no 'vette is going to go 280mph at any Cd with only 1000hp. Even at 1350lb, Honda's F1 car (totally trimmed out to 0.18 Cd) with 850hp only hit 248mph last month in Bonneville.
The "ram air opening" on the front fascia and the brake cooling ducts on the quarters.
ALSO the Z06 has a funtional rear lip/spolier on the trunk lid. This will provide a small amopunt of downforce as well as aerodynamic drag.
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From: Anna, OH
Originally Posted by Cheatin' Chad
The sledghammer idled at 900 rpm.I believe it also had a fully functioning HVAC system and a stock type interior.
I have seen video of these being driven on the street.
A 100% legitimate street car from all the information I have seen.
I have seen video of these being driven on the street.
A 100% legitimate street car from all the information I have seen.
It was the first car I'd seen able to touch the high banking and stay there!
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.......It had some deeeeeep gears loaded into it for that run. That, I can tell you.
And yes, factory AC and pretty much the factory interior.... and lots of tubing.
I agree.... I think it would be a little hard for a roots type. The twin squirrel has been done though. Both Lingenfelter and Callaway have both done twins, just aft of the block, next to the clutch/torque tube housing.
Well.... maybe.... just maybe that little burp of a rear spoiler that they added to the Z06. Knowing a little about aero/thermal myself (playing around at ViGYAN LaRC) I am sure that the increase in rear tire width, the open grille and the shorter wheel base (due to post vessel turbulence) might be the players here. I dunno. I can only speculate without instrumented and/or boundry layer smoke testing to give me an idea.
Just a question. But was your data product from a static model or from belt platen ?? I was just curious.....
Yup, true to that. I am trying to remember what factor the increase is. If I remember correctly, power output to achieve 280 for a given Cd would be like a factor of 4 ??
And yes, factory AC and pretty much the factory interior.... and lots of tubing.
Originally Posted by LTSpeed
The LS2 barely clears the hood as well. A roots blower--likely needed to get an LS7 to 1000hp--would not clear. A turbo setup would be have to be pretty wild to fit under there too.
Originally Posted by LTSpeed
Question: What aero changes make the C6 and Z06 different in terms of downforce? Answer: None.
Originally Posted by LTSpeed
All I can say is that my data shows them nearly identical at 0.323-0.336 with identical tires--depending on speed and suspension setup. I don't care what any magazine says when I have my own data. (BTW, I think we agree on the C5=0.29. On the C4 I don't know first hand.)
Originally Posted by LTSpeed
The original premise of this discussion was that Cd is more important than power for top speed. I'm only trying to point out that no 'vette is going to go 280mph at any Cd with only 1000hp. Even at 1350lb, Honda's F1 car (totally trimmed out to 0.18 Cd) with 850hp only hit 248mph last month in Bonneville.
Last edited by chicane; Aug 9, 2006 at 12:13 AM.
Launching!
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Originally Posted by LTSpeed
Question: What aero changes make the C6 and Z06 different in terms of downforce? Answer: None.
Read under the distinct design part. It mentions specifically of downforce, and of the z06's CD (apparently I was off, I didn't know the z06's was that low). I don't know how much, I know it isn't a huge ammount if memory serves me (a few hundred pounds at most), and the larger tires likely play a role in the high Cd.
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From: Anna, OH
Originally Posted by chicane
...was your data product from a static model or from belt platen ??
If I remember correctly, power output to achieve 280 for a given Cd would be like a factor of 4 ??
If I remember correctly, power output to achieve 280 for a given Cd would be like a factor of 4 ??
My guess is GM's numbers are based on static models. Most automakers numbers are--which is OK since it allows apples-to-apples comparisons. Now racers on the other hand....
As you know, the math on going 280 in a ground vehicle gets pretty hairy. But a C6 would need at least 1800fwhp to go 280mph, but that ignores things like parasitic drag and serious lack of traction. You'd need massive wings fore and aft, plus vent the exhaust straight up. (Traction is an issue jet and rocket cars don't fully have to deal with.)
These are some of the things that make a 280mph car less than streetable. That's what makes the Sledgehammer and Veryon so awesome to me--and scary!!
Last edited by LTSpeed; Aug 9, 2006 at 06:36 PM.
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Originally Posted by LTSpeed
It is a water-cooled rolling belt platen with multipoint boundary layer control. It also has controlled suction under the belt to keep it flat during high speed runs. It can run up to +/-15deg yaw and +/-5deg pitch.
My guess is GM's numbers are based on static models. Most automakers numbers are--which is OK since it allows apples-to-apples comparisons. Now racers on the other hand....
My guess is GM's numbers are based on static models. Most automakers numbers are--which is OK since it allows apples-to-apples comparisons. Now racers on the other hand....
I think I have an idea on your NDA's and where your data product is from now.... 0.323-0.336 it is. GM's is from a static test bed and doesnt quite account for much of the underbody aero and ride height transitions.... in my opinion.
Launching!
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Originally Posted by LTSpeed
As you know, the math on going 280 in a ground vehicle gets pretty hairy. But a C6 would need at least 1800fwhp to go 280mph, but that ignores things like parasitic drag and serious lack of traction. You'd need massive wings fore and aft, plus vent the exhaust straight up. (Traction is an issue jet and rocket cars don't fully have to deal with.)!
Here is a link to the Veyron GT
http://www.vwaudiforum.co.uk/forum/s...ead.php?t=1600
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There is a formula that has been proven several times and it is what most open road racers know that as the speed doubles, **the drag increases by the “SQUARE” (2X2=4). But what is also true, is that the horsepower requirement to double your speed, increases by the “CUBE”.
That means that if it requires100 horsepower to run 100+ mph in a specific vehicle”, it will take 800 hp (2X2X2=8) to push the “same car” to 200+ mph..... etc, etc.
**EDITED**
That means that if it requires100 horsepower to run 100+ mph in a specific vehicle”, it will take 800 hp (2X2X2=8) to push the “same car” to 200+ mph..... etc, etc.
**EDITED**
Last edited by chicane; Aug 10, 2006 at 10:16 PM.