IRS swap questions

[joemac]

I am considering an irs swap from a thunderbird or mark viii. From what I can gather it is 62.75 or 63" wide. A ranger rear axle is 56.5" wide. Is there room under there. I do not want to add fender flares.

Any ideas or know anyone who has done this? Pictures, I couldn't find much when I searched.

 

[Beanmachine7000]

Any ideas or know anyone who has done this? Pictures, I couldn't find much when I searched.

I have never heard of anyone doing this... Yet... It would be a neat idea though...

 

[midget]

Dont use the Tbird IRS its not the same as the mustang unit and there is very little aftermarket for them. Now the Mustang IRS would be a wicked upgrade handling wise and they have a large aftermarket and retain the 5x4.5 bolt pattern. The MN12 chassis IRS (tbird,cougar,mark III) for some info look up www.foxtbirdcougarforums.com its a web forum for late 80s tbirds but some have done the Mustang IRS swap and have very detailed information about the suspension that might help you out.

 

[Toreadorranger]

This is the back end of a Ranger from Ranger-forums.com

MN12 IRS. Found in Lincoln Mark VIIIs and Newer model T-Birds

 

[chvlfrk]

Eeewwwww.............

This is the back end of a Ranger from Ranger-forums.com
MN12 IRS. Found in Lincoln Mark VIIIs and Newer model T-Birds

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NOT much travel room IMO, you'd wipeout that upper arm with a good shot to the frame

 

[Toreadorranger]

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NOT much travel room IMO, you'd wipeout that upper arm with a good shot to the frame

Its a street truck. Thats how the stock suspension is minus the custom upperarms he made. He used the stock brackets cut from the car the IRS came from. The truck is a turbo SOHC 4.0L being used on the track (autocross style racing)

 

[joemac]

A popular upgrade for the MN12 cars is to swap over the cobra irs rear hubs as well as the front hubs to change to the 5x4.5 bolt circle. I have a '94 tbird and I have done this.

That picture of the upgraded irs is sweet. The stock upper arm is curved and I would engineer the same curve into it if I made an custom piece. That upper arm is nice though, I hadn't seen one up until now. It is correct to say there are not a lot of aftermarket parts for them.

I was planning to use airbags, or air rides bag with the shock inside. Cobra brakes are a simple upgrade and upgraded cobra half shafts can be used as well

It looks to me that the upper control arm in that picture is outboard of the frame if you look closely.

My main question is on the width. I am not too concerned with the other issues as I am pretty familiar with the MN12 IRS.

 

[TireIron]

you can also look at the newer explorers IRS... an 8.8 IRS designed to be under the weight and payload of the explorer cant be completely horrible, and finding a crashed or flipped explorer in the junkyard isn't that tough of a thing.

 

[dangeranger01]

you can also look at the newer explorers IRS... an 8.8 IRS designed to be under the weight and payload of the explorer cant be completely horrible, and finding a crashed or flipped explorer in the junkyard isn't that tough of a thing.

+1, and you keep the same width and bolt pattern.

 

[midget]

The MN12 tbird is alot wider than a ranger I had an 91 tbird stock car (used to beat some rules) and it barely fit on my 80" wide trailer with 8" tires its in fullsize width territory. Althoush that ranger looks like it has plenty of up travel if you think about the length of the arm and the fact it is an A arm the inside doesnt move much another odd thing is the fact the MN12 suspension uses really odd heavy spring rates I had 550lbs rear springs in my tbird and it was perfect for a tacky track but when it got rough it would bottom out. Ive seen guys use 800lbs rear springs in a fox body car thats been converted.