They do. Mustang Cobra. Ford did that about 15 years ago. The common Mustang uses a live axle, because for drag racing, the mustangs primary use, a live axle is better. But for the smaller crowd, like yourself, that are interested in circuit and whatnot, they have an option. The Mustang Cobras have a bit more power(different heads, and intake. Also available on the Ford Explorer) and IRS, plus some other suspension tuning. And you can buy an IRS kit for a Mustang from aftermarket places. Cobra conversion kit. Cobras are really great cars.