IRS on a 1970 Mustang Fastback

If you got the money, anything is possible. Heidts converts old jaguar IRS to fit mustangs. Also Control Freak Suspensions builds one for older mustangs that bolts where the leaf springs go. If you are going to go that extreme you might as well go all out with a coil over front, four wheel disc, frame ties, rack & pinion steering, the works. I will try to find a link, but there is a guy putting an old Jag rear in his mustang and was doing a write up on it, you can pick up a complete jag rear for around 600 bucks. The cobra IRS will work too, but again, lots of fabrication needed. Anyway, google search 67-70 mustang modifications, if im not mistaken I believe they have the same width and mounting locations, etc.

Check here. I believe they sellsuch kits.
IRS For Vintage Mustangs

Having installed both Heidt's IRS and a 2003 Cobra IRS I have some insight here. The Heidt's kit uses a Ford 9" center section and relatively light and strong. However, it is expensive and requires a great deal of fabrication. This is not a bolt on project. I do love the way the car rides and tracks on rough pavement.

The Control Freak kit looks great but with that price....

Dazecars Jag adaptation looks viable and is probably the least expensive option. Also very fab heavy.

The Cobra IRS is a complete and compact package. However, it is very heavy at about 300lbs. They can be purchased relatively inexpensively. Using the DVS mounting kit makes it nearly bolt in. I made my own brackets and coil over mounts but if I do it again I'll probably go the DVS route.

For my money on a 70 I would go with the Cobra IRS.

there are actually other options as well. you could use the kit that is based on the original mustang T-5 IRS concept that was done in the early 60's for the Falcon and adpted to the 65-66 stangs for shelby to test, they diecided against it because it didn't make the car any faster on a race track which is usually pretty smooth compared to city streets where I'm sure it will make all the difference in the world that kit can be found here

MUSTANG IRS - Independent Rear Suspensions For New & Classic Ford Mustangs

also Heidts has a new Pro-G IRS kit for early mustangs as well that is much different than their old kit where the installer has a lot of fab-work to do for installation, these new ones are a bolt-in and they also have the advantage of having had an upper control arm added over the olds which didn't use an upper control arm. that can be found here

http://www.heidts.com/_uploaded_fil...now_available_mustangl_retai__dealerl_may.pdf


you couls also try doing a search for "Green Hornet IRS" for a few rather undetailed photos of the experimental unit that Shelby used in the 68 gt-500 EXP coupe otherwise known as the Green Hornet. it is based on a 9" center section with a bolt in cradle and the one shown is a recreation of sorts that was fabbed up during the cars resto as the original unit had been yanked out before Ford sold the car. Personally thaty's my favorite option but it's one that you'll have to fab up yourself as there are known plans for it around anywhere that I can find. If you live close to Scottsdale AZ, I suppose you could try to get into Craig Jackson's collection to see that car as he is the current owner and maybe take some pics of the IRS.

if you consider attempting the Green Hornet IRS you'll need parts, some of which can be obtained from Heidts, Dutchman Motorsports, Kugel Components, etc. also do a search for ford 9 inch IRS and you can see some setups tht other people have done on everything from corvettes to late model GTO's and Camaros and even *** cars like Toyota Supras, etc.....

I hadn't seen that new Heidts kit yet. I wish they had that kit when I did mine.

I installed a jag in my 66 several years ago and it drives great. Kept it in the origional cradle to maintain the geometery. I can recommend it.

Marshall