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1. If the power to weight ratio is to go up one either drops weight or increases hp or both. Fuel economy demands suggest a drop in weight. There are no metal stamping machines to write off at Bowling Green and so there is no impediment to making an entirely carbon fibre c7. I understand that the cost is the same and the weight is about half. The Bowling Green plant would make an excellent place to try out mass production of carbon fibre vehicles.

2. Equal weight distribution does not mean the same thing as polar moment. A vehicle can have 50/50 weight distribution but have the weight at either ends (high polar moment) and be difficult to change direction or it can have 50/50 weight distribution and have most all of it's mass in the middle (very low polar moment). The current c6 is not mid-engined, no where near it. It has the engine at one end of a drive tunnel and the transmission at the other. Like it or not, physics dictates a mid-engined c7 corvette.

3. If the c7 is geogeous, looks like a 'vette and has decent storage space and is generally a very useable sports car, as is the c6, then I fail to see why people won't buy it. Would you turn down a c7 if it was the same price as a c6, had twice the power to weight ratio and could corner like no other??
 

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While you make a good case, making the move to a mid-engine configuration is much more than a technical decision. It steps away from what a Corvette has always been. Some will say it steps forward, but I maintain that it steps away. That doesn't make it a bad move, but it makes it a tough sell. Mid-engine designs are not the answer to everything, they bring some compromises of their own. While cars such as the Lamborghini Murcialago and Ferrari Enzo demonstrate the extreme capabilities of a rear mid-engine design, they are not cars you would want to live with or drive on an every-day basis. The Corvette is. I'm going to say something here that we really aren't supposed to say: the Corvette is not a racing car. It is a GT car, and a world-class one at that. The performance level available in even a standard C6, let alone the Z06, is light years ahead of what any car at any price was capable of not that many years ago. We tend to forget that. Overall, a mid-engined car can be made faster and better handling . . . but if it's less user-friendly (and all of them are), significantly more expensive (as it almost certainly would be), and doesn't strike all the right Corvette notes, it will be a failure. There's plenty of development room left in the current configuration, and I believe that's the path GM will follow.

Would a car similar to a Ford GT in configuration, but with classic Corvette styling cues, be close to the C7 of our dreams? Some may say yes, some no. Many would have a problem accepting it as a Corvette, and nowhere near as many people would want to drive it every day. It isn't as if the current C6 has a sub-standard performance level and handles badly. It doesn't. While I understand the rationale in wanting to "take it to the next level", going to a rear mid-engine configuration is not the only choice to make, or even necessarily the logical one. I guess we'll see.

Or not.
 

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1. If the power to weight ratio is to go up one either drops weight or increases hp or both. Fuel economy demands suggest a drop in weight. There are no metal stamping machines to write off at Bowling Green and so there is no impediment to making an entirely carbon fibre c7. I understand that the cost is the same and the weight is about half. The Bowling Green plant would make an excellent place to try out mass production of carbon fibre vehicles.

2. Equal weight distribution does not mean the same thing as polar moment. A vehicle can have 50/50 weight distribution but have the weight at either ends (high polar moment) and be difficult to change direction or it can have 50/50 weight distribution and have most all of it's mass in the middle (very low polar moment). The current c6 is not mid-engined, no where near it. It has the engine at one end of a drive tunnel and the transmission at the other. Like it or not, physics dictates a mid-engined c7 corvette.

3. If the c7 is geogeous, looks like a 'vette and has decent storage space and is generally a very useable sports car, as is the c6, then I fail to see why people won't buy it. Would you turn down a c7 if it was the same price as a c6, had twice the power to weight ratio and could corner like no other??
The Corvette is no less of a mid engine car then lets say a ferrari F430, they both have their engines in the same location in respect to the center of the car just one has it towards the front and the other towards the back. Infact being a front mid allows them to place the engine closer to the middle of the car..................
 

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:thud: :agree: People seem to never grasp the difference between the terms "mid-engined" and "rear-/front-engined."
 

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Discussion Starter #5
two points in reply:

1. With a carbon fibre design and the weight cut in half, there is plenty of design room to make the vehicle entirely useful as a daily driver.

2. Mid-engined or not, twice the current power to weight ratio is out of this world and makes for unheard of fuel economy in a performance machine.
 

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two points in reply:

1. With a carbon fibre design and the weight cut in half, there is plenty of design room to make the vehicle entirely useful as a daily driver.

2. Mid-engined or not, twice the current power to weight ratio is out of this world and makes for unheard of fuel economy in a performance machine.
No offense but you are going to need a lot more then carbon fiber to cut the weight in half.
 

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I'm a big fan of composite materials, but I think they can be problematic when they are the main structure on a street car. A daily driver needs to be readily repairable; composites tend to fail in a catastrophic fashion. This is ok for a body panel, but what happens when a fairly minor collision causes the entire unibody to spider-crack?
I would lean toward more light-weight alloys (a la the aluminum frame rails of the Z06) that have the potential to be repaired. The composites can be used to lighten body panels, suspension parts, etc., but I would prefer that we stay away from a complete CF structure.
 

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The cost of CF is higher than fiber glass. The carbon fibers are still expensive to produce. I agree with RTGordon about the use of a carbon fiber body (which you seem to be refering to). A 5 MPH bump will completely destroy the entire body panel. CF is strong, but is very brittle. The strength comes from the use of continous fibers layed in the direction of the loading. If the panel is damaged and the fibers are broken, the entire panel needs to be replaced to maintain the same strength.

If the engineers found a way to cut the weight of the car in half (approximately 1600 lbs) and keep it street legal they will go down in history as the greatest engineers in the history of the world. Go ask lotus how hard it is to get rid of weight.

The Zonda F has about twice the power to weight ratio as the corvette (510 hp/lbs vs 242 hp/lb) and it is definately not twice as fast. It also costs more than 10x as much.


It has been confirmed that the C7 will launch in 2013 and will be front engined for all the reasons detailed by other people. It will probably shave a few pounds as technology and processing advances, but most importantly, it will still distictly be a corvette and kick the crap out of 95% of cars on the road.
 

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I think what the over all idea here is that if GM made an all carbon fiber, mid engine corvette, it would not be used by hardly anyone as daily driver, occasional road course,auto x or drag race car. Instead, it would be very limited (by the owners, save but a few)in it's use and be thrust into obscurity due to poor sales, lack of public "face time" and high cost of repair. This is why you seldom see "exotics" as daily drivers or at the track, unless you live in the rare areas that there is much more money flying around than most of us here. By making the corvette into an "American Exotic" would really hurt it's image as the overall American dream car. It's got to be obtainable for the hard workers, it has to say "Corvette" at first glimpse, and ,imo, it has to be front engine ,rear wheel drive.
 

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I think he means a cf body weighs half the amount of an fg body.
I don't think that is what he meant, and I even doubt a cf body is half the weight of fiberglass.
 

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1. ... There are no metal stamping machines to write off at Bowling Green and so there is no impediment to making an entirely carbon fibre c7.

Sounds to me like RT understood exactly what was suggested - the elimination of all steel where possilble. RT hit it on the head. Driving an all carbon fiber monoque car on public roads would cost a fortune in insurance.

A small fender bender on todays vette would replace the fender only. In a monocoque body/chassis, it's possible that same fenderbender could require the replacement of the entire body. More Al, Mag and Ti in the chassis, CF pannels, CF support in the interior, maybe CF door structure, and polycarbinate side and back glass will just about bottom out the weight reduction capabilities for a street car given today's technologies, IMO.
 

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These were beautiful cars. I have several 35mm photos of the Indy shown at the LA car show in the mid 80's. I'd have sold my house to buy one of those if produced. It is certainly the apex of GM's rear-mid development starting with Zora's CERV I in the 60's to date. Time and again, the GM BOD refused to fund the production of a rear-mid corvette. Will this change in the future? I don't know. Why would they? They aren't car nuts and today's vette attains performance levels matching exoticars costing many times the corvette entry fee ... and sells well.

Has the Vette team pushed the front-mid performance capabilities as far as they can (with the SS?)? Maybe. But then who would have thought that a car with the engine hanging out BEHIND the rear axile could be engineered to the levels that Porsche has attained? If that awkward design can work, why can't front mid continue to be refined to new heights?

The best news to me is that the continued significant improvements made from C3 to C4 to C5 to C6 have made the vette, truely a world class automobile and have provided some assurance that we will see Corvettes produced for decades into the future. JMHO
 
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