C4 platform more stable than C5,C6,C7?

[Paul Workman]

Originally Posted by FU

Tears in my eyes after reading that

Kinda like the old axiom: "Twenty goes into 60 easier than 60 goes into 20!" (for much the same reasons...)

[mike100]

To me, I think the limits are higher on C5's and C6's, but when they let go everything happens faster. The rear transaxle has a bigger polar moment of inertia as they call it... a barbell with weight on both ends.

[Tony Davila]

Originally Posted by mike100

To me, I think the limits are higher on C5's and C6's, but when they let go everything happens faster. The rear transaxle has a bigger polar moment of inertia as they call it... a barbell with weight on both ends.

Now that is a great example.

[5ABI VT]

Yup thats pretty much it right there. Lots of people dont understand that about f/r weight distribution. It can still be 50/50.. but if the weight is further from the center... =D>

[mike100]

I've had my C6 on a track and it was just so confidence inspiring once the tires got up to temp. It was really balanced and communicated through the steering nicely. You really can't drive fast enough on the road to get to that level and that's why you should just leave the traction control on for the streets. The key to keeping the larger cubic inch cars (C6's and newer) on the road is keeping the very best tires on them.

A lot of the you tube crashes happen with cold or old tires with guys who turned everything off to drag race. Wet roads and corvettes suck as well. I'll give porsches credit there as with the weight of the drive train over the drive wheels they make better year round drivers.

The C4 can be driven fast if you are smooth into a corner, but it has a lower limit and it lets you know through road feel when you are getting close to it (sometimes). I went on a run with some newer vettes and it pushed and plowed on the really tight stuff... then the LS7 cars pretty much disappeared.

[Fully Vetted]

Originally Posted by Tony Davila

Makes since....., but I was wondering could the looseness aid in it not getting out of hand. Meaning, it is easier to force a stiff object (giggle) into a direction than it is to force a sloppy object. Sloppiness does not transfer the forces equally or as easily. Horse power and torque are absorbed by body flex.

I don't know, I'm not thinking too hard on this and everyone has a valid possible reason.

A stiffer chassis allows the suspension (whether old design or new) to do it's job of getting the power to the ground under various load conditions. When the chassis starts flexing the suspension components have to start compensating and handling loads it isn't designed for which makes it unstable. That's why I noticed a huge difference in stability under hard acceleration when I put on my No Flex bars. Like night and day...

[batchman]

I know I'm probably tiring to listen to but the alignment specs for a C4 are almost undriveable in any motorsports setting. The front spec is for positive camber (that's crazy talk!) and the rear was almost worse. Just compare how different the specs are from factory spec to the commonly published performance settings. Night vs day on the rack and on the track.

Originally Posted by Tony Davila

could the looseness aid in it not getting out of hand

I think you're onto something. The limits for this type of car are quite high - too high to rationally touch on the street, and the C4 spec keeps you from getting anywhere near them. I think those factory specs were mandated by lawyers. I think that by the time the C5 came around some of those lawyers had retired and by the C6 their voodoo dolls had been burned in effigy in the engineering department.

Cheers,
- Jeff

[rkreigh]

Originally Posted by 5ABI VT

Yup thats pretty much it right there. Lots of people dont understand that about f/r weight distribution. It can still be 50/50.. but if the weight is further from the center... =D>

polar moment of inertia.

sorry guys, the c5 on up handle much better. I've worked hard to make the old LSV outgun the c5 TT and it's not in the cards.

as frankie said, the C5 on up are stiffer and have improve suspension geometry, time and progress march on. the C4 is still very viable, but not on par with the modern stuff in a few respects.

while the c4 body has a bit better aerodynamic stability above 140 mph overall the c5 on up will out accelerate and out handle even the mighty Z on a racetrack. if you are driving fast enough to notice the difference on the street you are braver than me. The old LSV sticks like grim death, but doesn't quite have the "planted" feeling of the stiffer later vettes.

all that being said, I still prefer the old Z with the top off and the "targa brace bar" bolted in. the brace is stiffer than the top, and I love getting a clear earshot at the beast at WOT.

My c5 tt car will shade the Z, but it's not my weapon of choice unless racing

I'll say this though, I really liked the banski rods in back in place of the tie rods and dog bones. it freed up the rear suspension and took the deflection out, they are lighter, and really changed the personality of the car. now I need to upgrade the bushings in the front control arms and I think I'm done with the suspension/rim mods. (coil overs, banski rods and 18 CCWs)