ttown said:
We already have Limited slip and IRS has nothing to do with traction on ice/snow
You guys need to get an FWD, AWD, or a 4X4 for your winter rides. Lets not start the internet rumor that IRS is perfect for ice and snow, RWD/Torque make driving in ice/snow trickey no matter if you have a solid axle or IRS.
OK, the point that I am trying to make is this. I want a rear wheel drive performance car for less than 30,000$. The Mustang fits that bill, but it has been compromized, AFAIC. The Cobra is out of the price range.
I already have a 4x4, and that is what I drive in the snow most of the time. HOWEVER, if I buy another car, it is not going to be put away for the winter. That means it must have modest ability to go in the snow. Just as the miata does now.
The point I was making with my wife's miata is simply that rear wheel drive can do that, especially with IRS and limited slip. That way when one wheel needs to move over a chunk of ice, or a pothole, or expansion joint, or anything thicker than a dime, the other contact patch will maintain full traction on the width of the contact patch, not just the outside or inside edge, for braking or applying torque. The laws of physics work against a live axle in those situations, when one wheel moves, it directly affects the contact patch and traction, and spring/damper positions of the opposite tire, not matter what you try to do to pacify it. Once the coeficient of friction is overcome, the tires will spin until power is removed. The coeficient of friction of 1/3 of the tire's contact patch on ice or snow, is much less than the whole contact patch. you need all the traction you can get in ice or snow.
Face it. A live axle is fine in a truck, where the rigity is neccessary for the carrying loads. (even SUVs are going independent, though) but in a car, where that is less important, and tires have much shorter sidewalls, and less flex, an independent setup is better in pretty much every circumstance except perhaps drag racing. (usually drag slicks have much taller sidewalls, and much more flex) That is like saying that a spool will work for the street. NOT.
People who say that IRS is a price point consideration, I argue not. The original 60s/70s 240Z proved that. The Miata proves that. The RX8 proves that. pretty much every honest to god sportscar, regardless of price, in the last 30 years has had it. and many with much more than 300hp.
The mustang would be either cheaper, or more profitable if the
suspension engineers had only been expected to develop 1 rear end. It has been reported that the senior management forced the live axle issue to appease the minority of drag racers, and of those inexorably tied to the past. That is fine for them, but the price point argument is moot as far as I am concerned.
The IRS system has already been developed for the most part, both for the mustang specifically, and the DEW98 platform in general, which share the same rear hard points. the R&D costs are spread with IRS, where the new live axle
suspension development costs will have to be paid solely by Mustang customers. Per unit, that cost might actually be higher.
So, the point that IRS is not attainable on a car less than 30k, is not true.
The fact that live axles do just fine, is less than a stellar reason to stick to old technology when better is available for negligible, or no cost. I would argue the same for a six speed manual. No one says they have to use a T56, although that would be the better choice, but Getrag makes a nice one, too, I am told.
The traditionalist Mustang fans want live axles, great. But those of us who want a new car, should be able to get one, not a new car with old parts, cause they "do OK." /end Rant.