This article is within the scope of WikiProject Automobiles, a collaborative effort to improve the coverage of automobiles on Wikipedia. If you would like to participate, please visit the project page, where you can join the discussion and see a list of open tasks.AutomobilesWikipedia:WikiProject AutomobilesTemplate:WikiProject AutomobilesAutomobile
This article was copy edited by Dhtwiki, a member of the Guild of Copy Editors, on February 12–14, 2017.Guild of Copy EditorsWikipedia:WikiProject Guild of Copy EditorsTemplate:WikiProject Guild of Copy EditorsGuild of Copy Editors
Greglocock, I think the anti-roll characteristics of this spring setup are very significant and should be part of the lead. The base C7 Corvette didn't have a rear anti-roll bar for this specific reason. Also, this isn't something that is shared with more traditional coil sprung cars. With a traditional coil spring suspension, absent an anti-roll bar, the wheel rate is only a function of where each wheel is. So if the left wheel rate is 600lb/in it will be that regardless of where the right wheel happens to be. When an anti-roll bar is added the wheel rate of the left wheel is a function of the rate contributed by the ride spring + the rate contributed by the anti-roll bar. If the right wheel is higher than the left then the wheel rate is reduced and the opposite if the right wheel is lower. In most cars that behavior only exists because of the anti-roll bar. With the transverse leaf spring setup that behavior exists even without the anti-roll bar. Thus for the same suspension geometry and the same wheel rate in bounce the roll rate is significantly higher, higher to the point that with the C7 GM didn't need the rear anti-roll bar to hit their target roll rates in the base car. I believe this is also one of the characteristics touted in the Porsche patent on the subject. Springee (talk) 13:26, 1 June 2021 (UTC)[reply]
If the transverse leafspring is centrally pivoted than it has bounce rate but no roll rate. If you clamp the centre then the roll rate measured at the wheel is the same as the bump rate. On a live rear axle you get exactly the same transition by changing the spacing of the coil springs (or hotchkiss springs). In a conventional IRS without a roll bar of course the two rates are equal. There is no magic pudding. Or show me calculations. Greglocock (talk) 07:50, 2 June 2021 (UTC)[reply]
I think I see the confusion. A while back the article had some illustrations trying to show this.[[1]] If you have a cantilever spring mounted with a pivot in the center then the thing can either act like a seesaw or a spring. If you have a 100% rigid center mount then the left and right sides act as independent springs. If you use a widely spaced pair of mounts then you get the anti-roll effect. That can be seen in the FEA image that is still part of the article. It's also described in Lamm's book as well as several of the references. Essentially when you lift up the right side it forces the center down. That in turn lifts the left side. In this way it behaves like a traditional U shaped anti-roll bar in that pushing up on one side reduces the net spring rate/wheel rate of the other side. Unfortunately the scan of Lamm's comments is no longer available and I can't find my copy of Lamm's book. Edmunds does mention the anti-roll effect in their review of the Corvette C7's suspension [[2]]. Springee (talk) 16:07, 2 June 2021 (UTC)[reply]
