NEW MUSTANG REAR SUSPENSION
NEW MUSTANG REAR SUSPENSION
(OP)
What with the emphasis on dragstrip applications, does anyone know why Ford didn't offset the upper link to the right on the new Mustang rear suspension (ala the Jaguar C-Type)?
INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS Come Join Us!Are you an
Engineering professional? Join Eng-Tips Forums!
*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail. Posting GuidelinesJobs |
NEW MUSTANG REAR SUSPENSION
|
RE: NEW MUSTANG REAR SUSPENSION
My best guess is that it was not done because of packaging. Placed in the middle, the link can use the driveshaft tunnel. With an offset configuration, it might conflict with the rear passenger seat or be too short to maintain good geometry.
RE: NEW MUSTANG REAR SUSPENSION
Or, they could have cut costs even further by using quarter elliptics, clamped at both ends (forcing the spring into the secondary bending mode), and a single upper link, clamped at the rear and pivoting at the front. They'd have ended up with no Panhard and only one bushing. (It's fun to be a Monday morning quarterback.)
RE: NEW MUSTANG REAR SUSPENSION
RE: NEW MUSTANG REAR SUSPENSION
My /guesses/ are
A) An offset link would introduce an asymmetry in the rear suspension steering characteristic under braking and acceleration
B) They didn't think of it
C) Packaging (as Joest suggested)
D) They didn't care
E) They don't read eng-tips
F) Faint hope - they tried it and didn't think the result was worth the aggravation
G) They need as much wheelspin as they can get from the V6 to impress the customers.
Cheers
Greg Locock
RE: NEW MUSTANG REAR SUSPENSION
As for the braking comment, everyone brings this up and, if it wasn't for the success of the C-Type, I'd be inclined to accept it. I guess it worked because most of the braking is occurring at the front and, also, the asymmetry at the rear wouldn't really be noticed until you reach the limits of adhesion. And, after all, you don't want those rears locking up prematurely, anyway.
RE: NEW MUSTANG REAR SUSPENSION
For some time now, there has been discussion on a couple of other fora dealing with at least one aftermarket 3-link retrofit kit specifically for Mustangs, a similar Shelby Cobra replicar company option, and a number of one-off individual efforts. Not to mention some similar products under development for some of the earlier GM RWD cars.
Even small braking asymmetries might bring with them some ABS consequences. Or stability control system issues, if that was envisioned. In all fairness, the replicar product is slightly offset, but that car does not anticipate the installation of either ABS or stability control.
It may have been decided that taking the 3rd link loads off the pumpkin was preferable to forcing the right side axle tube to pumpkin attachment to handle the full torque reaction. That's what the previous 4-link did, hence the changes to the axle assembly would have been limited to the details of providing a single longitudinally-oriented ear instead of two angled ones.
Or maybe the rear suspension re-design budget was small enough that everybody decided to just keep it simple.
Norm
RE: NEW MUSTANG REAR SUSPENSION
You imply that rear suspension asymmetry is common among dragracers, but, apart from some static preloading, this is certainly not the case. The Ramchargers (a group of Chrysler engineers) attempted to utilize the Jaguar design back in the early sixties and there was a handful of imitators, but, unless something's happening recently of which I'm not aware, that's about it.
But, perhaps something is happening, for I was certainly not aware of these aftermarket kits to which you refer. I've been pushing this sort of thing...among dragracers...for about half a century now and it appears that I might actually see some activity before I die. They love their 4links so very much! Didn't think it would ever happen. In fact, I've recently started pushing adjustment of the 4links to place the IC above the no squat/no rise line on the right and below it on the left. Achieves the same effect as the asymmetric 3link and it allows them to keep their precious 4link.
Incidentally, it looks like someone else took high school latin. I'm going to make a search for these "fora" to which you refer. (I've been ribbed aplenty when I refer to turn "apices" and football "stadia.")
RE: NEW MUSTANG REAR SUSPENSION
Sites that I know of include corner-carvers.com and corral.net for the Mustang, Factory Five, and early Camaro fitments. Factory Five probably has its own site. Pro-touring (currently found at http://66.70.234.198/forum/index.php? ) and montecarloss.com discuss the Camaro and some other GM applications. Note that there is some overlap of project discussions and people involved across the boards.
Maybe I had a study hall in a room where Latin was taught during other periods. Unintentional learning via osmosis?
Norm
RE: NEW MUSTANG REAR SUSPENSION
Cheers
Greg Locock
RE: NEW MUSTANG REAR SUSPENSION
In braking, however, this ideal situation does not exist.
RE: NEW MUSTANG REAR SUSPENSION
Anyway, here is a pretty good picture of the layout
http://
RE: NEW MUSTANG REAR SUSPENSION
I think you actually kinda hit the nail on the head. They're real good at making tires bald. I've no real doubt that the trailing arm layout was a compromise between 'better that the awful thing we've been selling for the last 25 years' and $$$.
At best a Mustang is about 90% of a really good, fast car. And that's only after a lot of work. Regardless, when I was a bit younger I had a hell of a good time in many of them.
I guess you get what you pay for.
RE: NEW MUSTANG REAR SUSPENSION
RE: NEW MUSTANG REAR SUSPENSION
"The way the Mustang carves confidently into corners, making freeway on and off-ramps something to look forward to."
Liked that "shoelaces tied together" comment, though my favorite is still Tom McCahill's "It handled like a cannon ball falling down a chimney." Boy, I wish I could talk purty like that!
RE: NEW MUSTANG REAR SUSPENSION
I think he was thinking about Corvettes and Mustangs at the time!
Cheers
Greg Locock
RE: NEW MUSTANG REAR SUSPENSION
RE: NEW MUSTANG REAR SUSPENSION
Um, no.
Check out Ford Australia's Typhoon. 4 litre turbo charged with a blade type IRS. 550 Nm of right pedal fun. The killer load for blades is not simply engine torque.
I think your last two sentences are correct.
Cheers
Greg Locock
RE: NEW MUSTANG REAR SUSPENSION
RE: NEW MUSTANG REAR SUSPENSION
I think my main point is that there are other features of the suspension (ie tune and geometry) that cause blade failures, you just need enough grunt to set the problem off, but any additional torque just goes into relatively harmless wheelspin.
Cheers
Greg Locock
RE: NEW MUSTANG REAR SUSPENSION
RE: NEW MUSTANG REAR SUSPENSION
So far as the Mustang goes, for an IRS you'd be putting six hundred bucks and some kg into a car that sells for as little as 20000, for a benefit that few people would notice, and which certainly would not affect their buying decision.
I wish we'd kept a coil spring beam axle variant going in our car, it really was a sensible solution for real people.
Cheers
Greg Locock