Sportsdude

This sounds reasonable. I'm looking at the Callaway setup.

0Randy@DRM

I would like to add one more peice of real info in a thread full of regurgitated internet talk. The coilovers in as a package can be lighter as far as compont weight. But there is no coilover that has less unsprung weight then the leaf spring. That is about the only thing good about the leaf spring in my mind.

Randy

crabman

Good thread, missed it up in AK.

wishihad1-2

Keep in mind that the benefits to coilovers have a lot more to do with what is available in aftermarket parts than any inherent flaws in the use of a leaf vs coils. Had GM decided to use coilovers at the factory there would still be many people talking about the benefits of aftermarket coilovers vs the factory cost constrained parts.

In the aftermarket I strongly suspect the issue is the ready supply of coils and coil vendors vs leaf spring vendors. I’m sure Randy could offer some input on the number of choices he has for vendors of either component type. From out last conversation it really did sound like the aftermarket issues with the leaf were in the specific implementation, not inherent flaws in the idea or concept. In other words, it’s often easier for the aftermarket to offer a better tuned product because they have more flexibility in many ways.

Anyway, I suspect GM carefully weighed all the compromises (cost, reliability, packaging, service life, etc) and made what was probably the best choice under the circumstances. In the aftermarket world things are different. Almost certainly any aftermarket damper would cost quite a bit more in quantity than the parts GM is already using.

Since it was mentioned on page one, the leaf springs are fully independent just like the coil spring anti-roll bar set up. Both setups have “cross talk” in that both have a sway bar applying force from one side to the other. The leaf has no inherent disadvantages in that regard. So yes, if you were to remove the anti-roll bar and use coils the suspension would be both geometrically and force independent left to right. The leaf spring can not be force independent from left to right. However, until you are ready to remove your anti-roll bar that shouldn’t be an issue.

http://en.wikipedia.org/wiki/Corvette_leaf_spring
While this article has been referenced before, it has recently been updated with more illustrations so I figure it would be worth it for those who don’t fully understand the independent/non-independent part.

c5_4_me

Controversial subject. Leaf vs coil springs has to be up there with OEM ignition vs aftermarket ignition, in terms of controversy...

Anyway, it seems to me that a group of people are being left out. These folks would have very pertinent anecdotal evidence to add to this fire: Vette owners who have upgraded their SHOCKS ONLY and have left the stock Composite Transverse Monospring in place.

If you have Pfadt, Penske, Koni etc shocks on your car but still have the leaf springs, how does your car ride? I am especially interested because I am looking at a shock-only upgrade for my 01Z.

Jahan

[QUOTE=c5_4_me;1564866264]
Anyway, it seems to me that a group of people are being left out. These folks would have very pertinent anecdotal evidence to add to this fire: Vette owners who have upgraded their SHOCKS ONLY and have left the stock Composite Transverse Monospring in place.

QUOTE]

Anecdotal. THAT'S the problem. There simply aren't many people who:

1. Have DRIVEN/OWNED both (not ridden in) AND

2. Can TRULY evaluate a car's handling accurately AND

3. Understand suspension design well enough to speak intelligently about the issue.

To most people, better handling means lower, stiffer, and less roll. ANY aftermarket suspension package will SEEM like it handles better to about 99% of the population. Search the forum for people that upgraded their suspension in any way, and find me ONE who doesn't think the handling is improved. Ride complaints don't count.

In reality, unless you are Lewis Hamilton driving a certain pointy silver car in Bahrain this weekend, the unsprung mass difference is going to make ZERO difference to you. Literally ZERO. So, taking that argument out of the equation, the ONLY benefit to coilover's on a corvette is the aftermarket availability/price of different spring rates.

99% of the people on here DON'T need different spring rates. GM did a decent job selecing spring rates for these cars. The major opportunities for improvement are with shocks and tires. For a RACE CAR (Open track is NOT racing) you'd need higher spring rates. Other than that, there just isn't that much benefit to changing spring rates compared to shock valving or getting rid of runflats.

I'm not a "hater" of coil-overs or a "die-hard" leaf spring guy, but I am a suspension engineer, and you can't argue with the physics. Plus, I get annoyed with, as DRM put it, regurgitated internet talk. Especially when it's just plain wrong. It makes it hard for those of us who DO know something about something to find useful information.

c5_4_me

Thanks, Jahan.

It seems that your opinion backs up what I was planning to do with MY CAR, at least for the near future: Leave the CTM in there and upgrade the tires & shocks. Nice to know the thoughts on the subject from a suspension engineer.



Of course, coil-overs may be an option down the road.