Are Thunderbird IRS swaps common?

I'm curious if there's a common application out there were folks are using the Independent Rear Suspension out of 5.0 Thunderbirds in something else...

Reason being, I've got a chance to swap a beat-up thunderbird for my old non-running dually...

If I could easily sell the IRS to help offset costs...the 4 door Corolla might get an H.0. 5.0 and AOD...

Just curious.

Thanks,
Clem

Some parts are used in XR4Ti swaps, the entire assembly is made of a metal three times heavier than a black hole.

The Factory Five guys like the center diffs. Other then that, it's all scrap.

If the 5.0 is a HO it might be worth stripping anyways.

All 5.0 MN12 cars are HO, even though they're only rated at 205 hp. Due to the hood profile their intake is the same one as on the 94-95 Mustangs, not the Fox cars.

Some classic truck guys use the MN12 IRS, too. If it's a disc break rear the knuckles, calipers and e-brake cables are worth for selling to guys with rear drums. If the car has fold down rear seats you can get a few bucks for those parts if the upholstery is in decent shape.

You can save 35 pounds of weight by swapping the aluminum lower control arms and diff housing from a Lincoln Mark 8, which uses an almost identical suspension.

Your best bet if you make the trade is to sell what's left at tccoa.com.

Is it too heavy for the locost crowd?

I have seen the entire crossmember swapped under a '55 Chevy pickup. The truck already had a fiberglass nose and bed and a Mustang II frontend...

What he did was make a semi-box for each of the four subframe mounts, and the upper spring seats, and welded them to the frame. IIRC he used 1/4" plate. Each "box" was just two vertical triangles of steel and a square plate on the bottom.

Worked out a lot better than the solid axle he had been running. Not much sprung weight relative to unsprung before he went IRS.

Check out www.truckirs.com.

far too heavy.

heres my question on the mn12 IRS - do they make a coil over kit that replaces the coil springs?

i have one sitting here - i bought a 93 t-bird specifically for the rear end(and made money after selling the engine/trans and scrapping the car)

Isn't that the same setup that was the basis for the Monster Miata?

patgizz wrote: heres my question on the mn12 IRS - do they make a coil over kit that replaces the coil springs? i have one sitting here - i bought a 93 t-bird specifically for the rear end(and made money after selling the engine/trans and scrapping the car)

The short answer is no...HOWEVER, when the supply of Bilstein shocks for the MN12 ran out people started using the 03-04 Cobra rear shocks, and that seems to work pretty well. Maximum Motorsports does a Cobra rear coilover conversion, but no one with an MN12 has tried it out yet because we don't think it will work given the factory MN12 upper shock mount arrangement. That, and since the stock upper AND lower shock mounting locations were never meant to carry the weight of the car (and it's a lot of weight) I'm a little afraid that the lower control arm shock mount could break. For a lighter, custom vehicle though, the MM Cobra coilover kit might work.

I appreciate the info all...

Turns out I traded the truck this weekend for something else...however, if I want to buy this thunderbird, I can proceed with the knowledge youv'e given me here. Basically...given my area, I probably won't assign any value to the IRS for parting-out purposes.

Thanks again, Clem

JmfnB wrote: Some parts are used in XR4Ti swaps, the entire assembly is made of a metal three times heavier than a black hole.

I just spouted milk out my nose. Thanks for the laugh!!