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RogerR · 01-24-2013, 12:08 AM

Gixxersixxerman,

I would say you are right, this is an evolutionary car. Even though almost no parts are carry over it's clear the chassis is an evolution of the C6 which was of course an evolution of the C5. The C4 was actually a very revolutionary car but I also think it was less than the sum of it's often very interesting parts. The C3 was an evolved C2. The C2 was revolutionary, the C1 wasn't.

So the C2 strikes me an revolutionary mostly because it was one of the earliest cars with a multi-link rear independent suspension. Funny that some people think the car still has a rigid axle thanks to the leaf spring yet the Corvette was one of the first cars to have what would be considered a modern IRS. Prior to the Vette, Jag E-Type and Lotus that all came out about the same time IRS suspensions were typically swing axles. The two Brits and the Corvette were the first to have a multi-link rear suspension. I mean BMW would still be using semi-trailing arm rear suspensions into the 2000s.

The C4 was really interesting on many levels. It's a car with lots of creative design ideas and several firsts. In addition to being the first to use fiberglass leaf springs front and rear it also was the first production car with forged alloy suspension arms. The first LCD instrument display. One of the earliest 5 link multi-link rear ends and a pioneer in several other areas. Still, the chassis wasn't strong enough to be a targa (it was designed to be a T-top but the higher ups said go targa). The interior also struck me as cheap feeling.

The C5 clearly was a revolutionary design. It wasn't perfect but the level of chassis rigidity and light weight was revolutionary at the time. Also if you read the book All Corvettes are Red (a must read for any car fan, even ones who don't like GM cars) you can see that much of the turn around at GM really started with the C5.

vtmike,
The non-linear spring rate is not inherent in the spring. As with coils the linearity of the spring rate can be adjusted as the engineers see fit. A more progressive rate is common on road cars as it helps the ride. Basically it's a trade off.

"I also don't like the fact you have the spring (crosstalk effect) and roll bar providing the roll resistance but functioning in a different manner from one another. It seems like it would make it much more difficult to set up."
The crosstalk effect is identical to that of a traditional roll bar. The wheels don't know how the suspension is connected. What the left wheel knows is, at a given position of the left wheel plus a given position of the right wheel, the suspension arm is pushing down with X N of force. Some of that force comes from the ride spring and some from the sway bar. The wheel doesn't know the difference. The leaf can be tuned such that from the POV of the suspension, if you looked at a force vs displacement surface plot, you couldn't tell if the car used leaves or coils. It simply makes no difference.

You might be correct that it's more difficult to setup. However, GM has the tools to set this up. What ever the target ride and roll rates, they can hit it with either coils or the leaf. It's just the leaf will be lighter and package better in the process (and suck more money away).

I'm really looking forward to the new Mustang as well. I haven't driven the current 5.0 cars. However, I have driven the older models. I was actually really blown away by an '04 Cobra. I think the Fox body was a junky car but MAN I couldn't believe how SMOOTH the motor was. I mean I expected power and noise. The engine delivered. What I didn't expect was vibration levels that BMW would have been pleased with. It's funny, I'm quick to sing the praises of the power, compact size and light weight (about the same as a Nissan V6) of the GM LS V8s. However, the Corvettes I've driven always felt just a bit cammy. It was never a stupidly smooth motor like a BMW I6. The Ford V8 in the old Cobra wasn't light, it wasn't efficient and it wasn't small. But it was smooth and really had great character.

Go figure.

01-24-2013, 12:08 AM	#348
RogerR Member Join Date: Jan 2013 Drives: -- Location: Was Cali Posts: 24 Thanks: 0 Thanked 23 Times in 8 Posts Mentioned: 1 Post(s)	Gixxersixxerman, I would say you are right, this is an evolutionary car. Even though almost no parts are carry over it's clear the chassis is an evolution of the C6 which was of course an evolution of the C5. The C4 was actually a very revolutionary car but I also think it was less than the sum of it's often very interesting parts. The C3 was an evolved C2. The C2 was revolutionary, the C1 wasn't. So the C2 strikes me an revolutionary mostly because it was one of the earliest cars with a multi-link rear independent suspension. Funny that some people think the car still has a rigid axle thanks to the leaf spring yet the Corvette was one of the first cars to have what would be considered a modern IRS. Prior to the Vette, Jag E-Type and Lotus that all came out about the same time IRS suspensions were typically swing axles. The two Brits and the Corvette were the first to have a multi-link rear suspension. I mean BMW would still be using semi-trailing arm rear suspensions into the 2000s. The C4 was really interesting on many levels. It's a car with lots of creative design ideas and several firsts. In addition to being the first to use fiberglass leaf springs front and rear it also was the first production car with forged alloy suspension arms. The first LCD instrument display. One of the earliest 5 link multi-link rear ends and a pioneer in several other areas. Still, the chassis wasn't strong enough to be a targa (it was designed to be a T-top but the higher ups said go targa). The interior also struck me as cheap feeling. The C5 clearly was a revolutionary design. It wasn't perfect but the level of chassis rigidity and light weight was revolutionary at the time. Also if you read the book All Corvettes are Red (a must read for any car fan, even ones who don't like GM cars) you can see that much of the turn around at GM really started with the C5. vtmike, The non-linear spring rate is not inherent in the spring. As with coils the linearity of the spring rate can be adjusted as the engineers see fit. A more progressive rate is common on road cars as it helps the ride. Basically it's a trade off. "I also don't like the fact you have the spring (crosstalk effect) and roll bar providing the roll resistance but functioning in a different manner from one another. It seems like it would make it much more difficult to set up." The crosstalk effect is identical to that of a traditional roll bar. The wheels don't know how the suspension is connected. What the left wheel knows is, at a given position of the left wheel plus a given position of the right wheel, the suspension arm is pushing down with X N of force. Some of that force comes from the ride spring and some from the sway bar. The wheel doesn't know the difference. The leaf can be tuned such that from the POV of the suspension, if you looked at a force vs displacement surface plot, you couldn't tell if the car used leaves or coils. It simply makes no difference. You might be correct that it's more difficult to setup. However, GM has the tools to set this up. What ever the target ride and roll rates, they can hit it with either coils or the leaf. It's just the leaf will be lighter and package better in the process (and suck more money away). I'm really looking forward to the new Mustang as well. I haven't driven the current 5.0 cars. However, I have driven the older models. I was actually really blown away by an '04 Cobra. I think the Fox body was a junky car but MAN I couldn't believe how SMOOTH the motor was. I mean I expected power and noise. The engine delivered. What I didn't expect was vibration levels that BMW would have been pleased with. It's funny, I'm quick to sing the praises of the power, compact size and light weight (about the same as a Nissan V6) of the GM LS V8s. However, the Corvettes I've driven always felt just a bit cammy. It was never a stupidly smooth motor like a BMW I6. The Ford V8 in the old Cobra wasn't light, it wasn't efficient and it wasn't small. But it was smooth and really had great character. Go figure.