Is "Corvette-rule" necessary?
11-18-2002 | 02:33 AM
#31
Registered User
Joined: Jul 2002
Posts: 2,473
From: South Bend, Indiana
Originally posted by Chuck!
If I had to guess at it I'd say the auto manufacturers under rate cars so they can follow them up. The 03 cobra is a good example. Lets say they put down a conservative 360 rwhp and est 15% drive train loss. That's a 415 hp car, 25 above advertised hp ratings. That means buyers would be looking for something along the lines of 430-440 for the Cobras follow up.
But now if Ford wants to say hey, the 04 Cobra is going to make 405 hp, they'll have no problems doing so. They'll put on a less restrictive exhaust and open up maybe 5-10 rwhp and still be above expected numbers. Then the 05 Cobra can put down 415-420 with no problems, instead of having to redesign the intake and make better flowing heads, dropping all kinds of unecessary money into R&D.
If I had to guess at it I'd say the auto manufacturers under rate cars so they can follow them up. The 03 cobra is a good example. Lets say they put down a conservative 360 rwhp and est 15% drive train loss. That's a 415 hp car, 25 above advertised hp ratings. That means buyers would be looking for something along the lines of 430-440 for the Cobras follow up.
But now if Ford wants to say hey, the 04 Cobra is going to make 405 hp, they'll have no problems doing so. They'll put on a less restrictive exhaust and open up maybe 5-10 rwhp and still be above expected numbers. Then the 05 Cobra can put down 415-420 with no problems, instead of having to redesign the intake and make better flowing heads, dropping all kinds of unecessary money into R&D.
11-18-2002 | 12:18 PM
#33
Registered User
Joined: Mar 2001
Posts: 13,711
From: The Golden State
Originally posted by redzed
Newsflash: A 2000 Camaro SS actually put MORE horsepower on the road than a '00 Corvette - blame the rear transaxle for extra friction. I had it on good authority that the performance disparity was solely down to weight.
Newsflash: A 2000 Camaro SS actually put MORE horsepower on the road than a '00 Corvette - blame the rear transaxle for extra friction. I had it on good authority that the performance disparity was solely down to weight.
Just to add to that, the SS you mention has a jerryrigged dual exhaust system (the exhaust on the driver's side is almost flat for a couple of feet to fit under the crossmember) and Camaro's LS1 has a slightly more agressive cam than Corvette to begin with (without it, it would likely put out 306hp like the similarly breathing-restricted Holden Monaro......Australia's noise standards).
Last edited by guionM; 11-18-2002 at 12:21 PM.
11-18-2002 | 01:50 PM
#34
Banned
Joined: Mar 2002
Posts: 1,954
Originally posted by guionM
Yet another example of the "Corvette Rule" being a non-issue. But in your example, it's rear-wheel horsepower, not the rated advertised net. But it still proves the point, and it's not a secret with GM (one group developed both cars) or with Corvette enthusiasts.
Just to add to that, the SS you mention has a jerryrigged dual exhaust system (the exhaust on the driver's side is almost flat for a couple of feet to fit under the crossmember) and Camaro's LS1 has a slightly more agressive cam than Corvette to begin with (without it, it would likely put out 306hp like the similarly breathing-restricted Holden Monaro......Australia's noise standards).
Yet another example of the "Corvette Rule" being a non-issue. But in your example, it's rear-wheel horsepower, not the rated advertised net. But it still proves the point, and it's not a secret with GM (one group developed both cars) or with Corvette enthusiasts.
Just to add to that, the SS you mention has a jerryrigged dual exhaust system (the exhaust on the driver's side is almost flat for a couple of feet to fit under the crossmember) and Camaro's LS1 has a slightly more agressive cam than Corvette to begin with (without it, it would likely put out 306hp like the similarly breathing-restricted Holden Monaro......Australia's noise standards).
year(s).
11-18-2002 | 04:02 PM
#35
Registered User
Joined: Jun 2002
Posts: 2,979
A funny thing happened on the way to GM....
A lot of interesting points have come out here, but other points about old-time GM inter-divisional dealings should be highlighted.
GM used to be broken up into two major groups - component divisions (like Fisher Body, Hydramatic, and Rochester) and marketing divisions (originally called MOTOR DIVISIONS).
The component divisions were responsible for pretty much everything besides the motors and the front clip. The motor divisions had responsibility for the motors, chassis, front clip, marketing, etc...
This was an offshoot of the original state of the automobile industry, which had "coachbuilders" who would build a body over a running chassis provided by, say, Buick or Oldsmobile or Cadillac. Fisher Body and Fleetwood were both coachbuilders originally.
Then, the component divisions began to gain ascendancy in some respects over the motor divisions.
2 divisions at GM used to get whatever they wanted. Cadillac and Chevrolet. If Cadillac wanted an extra interior color, they got it. If Chevrolet wanted an extra body character line, they got it.
If Buick or Oldsmobile wanted either of those things, they got told where to stick it because they never had the volume to justify the expense.
This was a MAJOR reason for the downfall of Fisher Body at GM, and the elimination of Fisher and the many other component makers as divisions. Buick, Olds and Pontiac were traditionally the "poor relations" compared to Chevrolet and Cadillac and traditionally had a much harder time getting the things they wanted. This made them unhappy - and made Fisher Body a big target.
Nowadays, there are no "motor" divisions. NAO Engineering does all of the engineering for the vehicles, and the former motor divisions MARKET them - including initial marketing work that defines the vehicle and sets up the business case to justify its production. Powertrain makes motors and transmissions. Rochester makes electronics. Metal Fab makes body panels. But they all answer to NAO for vehicle level engineering and then the marketing divisions go out and sell the cars. So, nowadays, instead of having Fisher Body and Pontiac screaming at each other, you have NAO Engineering and the marketing divisions screaming at each other.
Now, the flipside of this is that if a marketing division like Cadillac wants to build a V12 supercar, they have to sell it to senior GM management (as do all of the marketing divisions), and it has to make business sense. V12 supercars don't make a lot of sense financially unless you are using them as a "halo" car (how many times has Lamborgini been bought and sold????).
One other point...
Chevrolet considers absolutely nothing to be in Corvette's class. It is over $30,000 less expensive than Viper, half the cost of the fast Porsches, and the Mustang buyer is not in the market for a Corvette.
The only competition possible for Corvette comes from inside GM - XLR. But I would imagine the demographics of the two cars are probably very different, and the XLR buyer really doesn't care as much about having 400hp as he does the styling of the car and how cushy it is. The is a small, but VERY vocal, minority of Corvette owners who care very deeply about how fast the car is and how well it handles.
A lot of interesting points have come out here, but other points about old-time GM inter-divisional dealings should be highlighted.
GM used to be broken up into two major groups - component divisions (like Fisher Body, Hydramatic, and Rochester) and marketing divisions (originally called MOTOR DIVISIONS).
The component divisions were responsible for pretty much everything besides the motors and the front clip. The motor divisions had responsibility for the motors, chassis, front clip, marketing, etc...
This was an offshoot of the original state of the automobile industry, which had "coachbuilders" who would build a body over a running chassis provided by, say, Buick or Oldsmobile or Cadillac. Fisher Body and Fleetwood were both coachbuilders originally.
Then, the component divisions began to gain ascendancy in some respects over the motor divisions.
2 divisions at GM used to get whatever they wanted. Cadillac and Chevrolet. If Cadillac wanted an extra interior color, they got it. If Chevrolet wanted an extra body character line, they got it.
If Buick or Oldsmobile wanted either of those things, they got told where to stick it because they never had the volume to justify the expense.
This was a MAJOR reason for the downfall of Fisher Body at GM, and the elimination of Fisher and the many other component makers as divisions. Buick, Olds and Pontiac were traditionally the "poor relations" compared to Chevrolet and Cadillac and traditionally had a much harder time getting the things they wanted. This made them unhappy - and made Fisher Body a big target.
Nowadays, there are no "motor" divisions. NAO Engineering does all of the engineering for the vehicles, and the former motor divisions MARKET them - including initial marketing work that defines the vehicle and sets up the business case to justify its production. Powertrain makes motors and transmissions. Rochester makes electronics. Metal Fab makes body panels. But they all answer to NAO for vehicle level engineering and then the marketing divisions go out and sell the cars. So, nowadays, instead of having Fisher Body and Pontiac screaming at each other, you have NAO Engineering and the marketing divisions screaming at each other.
Now, the flipside of this is that if a marketing division like Cadillac wants to build a V12 supercar, they have to sell it to senior GM management (as do all of the marketing divisions), and it has to make business sense. V12 supercars don't make a lot of sense financially unless you are using them as a "halo" car (how many times has Lamborgini been bought and sold????).
One other point...
Chevrolet considers absolutely nothing to be in Corvette's class. It is over $30,000 less expensive than Viper, half the cost of the fast Porsches, and the Mustang buyer is not in the market for a Corvette.
The only competition possible for Corvette comes from inside GM - XLR. But I would imagine the demographics of the two cars are probably very different, and the XLR buyer really doesn't care as much about having 400hp as he does the styling of the car and how cushy it is. The is a small, but VERY vocal, minority of Corvette owners who care very deeply about how fast the car is and how well it handles.
11-18-2002 | 04:57 PM
#36
Registered User
Joined: Mar 2001
Posts: 13,711
From: The Golden State
Very interesting post pacerX. It kind of puts in perspective the fact that Kurt Ritter & Chevrolet desparately want not just a Camaro, but a RWD sport sedan, but have to take a back seat to alot of other projects other divisions have on the agenda.
I guess if this were the old days, we'd see a new Camaro & sports sedan at Chevy, while all the good stuff that's comming from Pontiac (ie: the high powered Grand Am w/ AWD) would be taking a back seat. I can see the business sense behind this, looking out for the welfare of the entire company instead of just 1 or 2 divisions, and it would also be cheaper having just one entity doing all the standardized work.
But the down side to this is glaring: it makes it much tougher to bring "halo cars" to market if it isn't profitable. Corvette is profitable enough to pay it's own way and have money left over, GTO's investment is simply certification not development (which was handled by the highly profitable & cheap to run Holden subsidiary) and will no doubt make it's money back & then some over a 2 -3 year run. Yet, Solstice is having a tough time comming to market while even Bob Lutz struggles to find a financial way to justify it, and why Camaro isn't with us any longer.
Your post puts things in clearer perspective. Doesn't make things any more pleasant, but at least it's understandable.
You rightly pointed out that the losses in Corvette occured because of the friction from the rear transaxle that Camaro's more traditional set up doesn't have. That would mean both engines would at least put out the same horsepower, but would suffer different losses due to the rest of the drivetrain.
That's where rear-wheel horsepower measurements apply. So while the SS actually puts out about 5 less horsepower than Corvette due to breathing restrictions, when measured at the rear wheels, the difference in drivetrain losses between SS & the Vette, the SS puts more of that power on the road (more rear wheel horsepower). I believe that's what you're trying to say.
My additional point was that the 340 hp SS is the dual exhaust, better breathing version. Standard SSs have 325hp, the dual exhaust version is the one that has 345.
http://www.slpeng.com/2002camaross/
The 99-00 versions have 330.
https://www.camaroz28.com/articles/99camaross/
I guess if this were the old days, we'd see a new Camaro & sports sedan at Chevy, while all the good stuff that's comming from Pontiac (ie: the high powered Grand Am w/ AWD) would be taking a back seat. I can see the business sense behind this, looking out for the welfare of the entire company instead of just 1 or 2 divisions, and it would also be cheaper having just one entity doing all the standardized work.
But the down side to this is glaring: it makes it much tougher to bring "halo cars" to market if it isn't profitable. Corvette is profitable enough to pay it's own way and have money left over, GTO's investment is simply certification not development (which was handled by the highly profitable & cheap to run Holden subsidiary) and will no doubt make it's money back & then some over a 2 -3 year run. Yet, Solstice is having a tough time comming to market while even Bob Lutz struggles to find a financial way to justify it, and why Camaro isn't with us any longer.
Your post puts things in clearer perspective. Doesn't make things any more pleasant, but at least it's understandable.
Originally posted by redzed
My analogy applied to the production Camaro SS, not one particular lash up. The horsepower rating should have read as 340hp rather than 320hp in '99 and '00. In essence, this represented more power on the road than a C5 of the same
year(s).
My analogy applied to the production Camaro SS, not one particular lash up. The horsepower rating should have read as 340hp rather than 320hp in '99 and '00. In essence, this represented more power on the road than a C5 of the same
year(s).
That's where rear-wheel horsepower measurements apply. So while the SS actually puts out about 5 less horsepower than Corvette due to breathing restrictions, when measured at the rear wheels, the difference in drivetrain losses between SS & the Vette, the SS puts more of that power on the road (more rear wheel horsepower). I believe that's what you're trying to say.
My additional point was that the 340 hp SS is the dual exhaust, better breathing version. Standard SSs have 325hp, the dual exhaust version is the one that has 345.
http://www.slpeng.com/2002camaross/
The 99-00 versions have 330.
https://www.camaroz28.com/articles/99camaross/
Last edited by guionM; 11-18-2002 at 05:15 PM.
11-18-2002 | 05:34 PM
#37
Disciple
Joined: Dec 2000
Posts: 1,479
Originally posted by guionM
My additional point was that the 340 hp SS is the dual exhaust, better breathing version. Standard SSs have 325hp, the dual exhaust version is the one that has 345
My additional point was that the 340 hp SS is the dual exhaust, better breathing version. Standard SSs have 325hp, the dual exhaust version is the one that has 345
The SLP exhaust (rated at 10 HP) isn't a "dual" exhaust, it has dual - twin outlets from a single muffler. The improved flow comes from the 3" intermediate pipe ... the same technique most aftermarket exhausts use.
Another 10 rated HP come from the optional air lid.