New Mustang;

It never "went back" as is has always had one. The only Mustang to have an IRS was the '99+ Cobras. The main reason they stayed with the solid axle was for cost savings. They have redesigned the solid axle to perform much better than on past Mustangs. Most reviews have praised its performance considering its design is not IRS. One other reason is that many, if not a majority, of Mustang fanatics prefer the solid axle for its light weight, strength and simplicity for those that change gears, axles etc. It really didn't matter to me which way they went because I can see the value in both axle designs.

Thanks!.......I wasn't aware that only the cobra's were IRS. I thought after 99 all were. Years ago I had a Shelby GT-350, {66} I set the front-end up to "R" model specs. & it handled very!! well. Never should have sold it :(...........Ron

For somebody that knows practically nothing, how much *cornering* advantage do you actually gain by having an independent rear suspension? I know a lot of the ricers like to brag that they have IRS, but most of these cars are FWD so it's a little different.

For off-road applications, I can imagine that you'd have a major advantage by going with an IRS. I'm not really sure about a Mustang, though.

On a side note, I will mention that when I had my 02 Mustang GT convertible (sold it back in November :-( ) there was this one section of road that always seemed to throw me all over the place. It's a right-hand corner with pot holes on the inside. If I didn't stay to the outside of this corner, my rear end would bounce all over the place. This was unlike my friends 1992 Honda Civic VX (which I would assume has IRS since it's FWD) that was barely affected by the bumps. Would IRS have helped me in this situation?

Yes it would have because the IRS is better when the road has irregularities (i.e. potholes etc.) but on relatively smooth roads the difference isn't nearly as great. While overall the IRS is a better suspension from a handling aspect, like most things, it has trade-offs. To make it as strong as a solid axle adds weight to a design that is already heavier. It is more costly. Also, IMO, IRS can't touch a well built solid axle at the drag strip. The '03-'04 Cobra owners that are serious about drag strip performance ditch the IRS and plug in a good old 8.8" rearend.

That's what I figured. And I agree; I can't see how IRS could even begin to be as reliable as a solid rear axle on the strip. That's why I wanted to stress cornering abilities, as this is where I tend to believe IRS shines.

Like you said, both have advantages and disadvantages. I'm personally more interested in road racing (yes, on the track where that type of driving belongs) than drag racing, which is why I'd probably opt for a IRS over solid rear axle if I were building myself a race car.

Thank you for the information,