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Discussion Starter #1
ony one fully swapped the rear suspension to an IRS. Like the vets or many of the newer luxury cars. I know its work, but was wondering how feaseable it is, and how/if it helped.
 
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Discussion Starter #2
I know of a few people (including myself) that have looked into it. There is no "bolt in" (or weld in) kit available, and as far as I know no-one has actually done this swap.

I do think there would be some notable handling benefits (assuming it is set up properly) to do this. I do NOT think the swap would be remotely cheap though....I'm figuring at least $3K and losing the ABS to get it done.
 
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Discussion Starter #3
Well from the past, unless things have changed.
There are only 2 reasonable options, the vette or Jag rearend.
A buddy of mine found a Jag reaerend in a junk yard and had it shortened to fit in an S-10.
The whole frame on the truck was custom, so that was easy to the point of building the frame around the rearend.
Either one you choose, unless they have changed in the last 4 years, the rear ends get mounted to the cars at the center. This means that you would have to build the rear section of the frame. This would be a lot harder in a car than it was on a truck with no bed on it, espcially since you can raise the bed floor easier than the floor pan of a car.
 
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Discussion Starter #4
yes, the rear end is gonna be mostly custom anyways...

So it is possible, but not cheap. DAMN, what are the horsepower ratings on a IRS. If one was to swap out a vett rear, what year range would someone be looking at... like c5 or a c5 body?

This is not an immediate mod, but i would not complain with that smoother ride or the better suspension handling...
 
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Discussion Starter #5
Anything is possible with a torch and a mig.
I think either rearend would handle the power fine.
 
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Discussion Starter #6
I think you would be much better off starting with a Jag rear because a Jag would be much closer in weight to a b-body than a Vette is.
 
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Discussion Starter #7
This would be a fun modification. The traditional hot rodders use kits like this .

Just plug and play! :D

Mike
 
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Discussion Starter #8
Originally posted by BAD ROD:
This would be a fun modification. The traditional hot rodders use kits like this .

Just plug and play! :D

Mike
What sort of axles do they use? Heres another COMPANY that does IRS conversions. They use Corvette rear ends (Dana 36/44). Wish I had the $$$.

EDIT: Which one of those 2 companies would be a better setup?
 
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Discussion Starter #9
3 grand or 4 grand... thats the dif.. the 4 grand comes with willwood disk breaks. yeah, i wish i had the money...
 
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Discussion Starter #10
Kugel has IRS setups that use 9" Ford centers for your hi-output situations.

I'd take one with a quickchange center for the cool factor, however. That'd be handy for your highway, drag strip, or road race gearset changes.
 
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Discussion Starter #11
There are fords that have these already.
I think maybe they were lincolns?

I had the chance to pick one up for $500 that included the whole sub frame. They come with the ford nine inch rear ends and air bag suspensions.

With a little welding it should have been a relatively cheap and easy swap. I didn't have the cash or a welder or the knowledge to use a welder or I would have done it myself.

Look at recent rear drive lincolns and see if you can find one.

I kick myself now for not buying this rear end...
 
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Discussion Starter #12
Quite a find, you may have just come up with the info needed for someone to actually do this mod.
 
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Discussion Starter #13
The only question would be if the rear end was wide enough. But I am sure widening such a rear end would be simpler since it is already setup for a heavy car.

The guy who had it used to work for JTS in Western Michigan but no longer works there. His name is Jay. I mention this because Jay has done ALOT of the Bbody rear ends in the midwest.
I am sure he could tell you what rear end he had.

I wanna say a mark series ford car from the 90's.
 
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Discussion Starter #14
Its doable and not for 3 - 4k

Concours West build a weld in kit that runs about 600.00 delivered. I get Jag rearends all the time and sell them on eBay for about 650 - 750.00. The relocutor for the ABS is doable it just takes a little machine work.

The late 70's thru mid-eighties XJ6/XJS rear ends are within a 1/2 inch of ours, widthwise, and the bolt pattern is 5 x 4.75 (GM small 5 lug pattern). Many but not all Jag IRS' are limited slips, all of them are Dana 44's. You'd need a custom driveshaft since the pinion flange is different (Dana Spicer makes the adapter). It should work really well.
 
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Discussion Starter #15
Originally posted by elixir:
With a little welding it should have been a relatively cheap and easy swap.
In theory, but unfortunately theory doesn't hold a lot of weight when it comes to swaps like this. If you've ever done such a swap, whether it be on a modern car or a street rod, you know what I'm talking about.
 
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Discussion Starter #16
Originally posted by threeimpalas:
</font><blockquote>quote:</font><hr />Originally posted by elixir:
With a little welding it should have been a relatively cheap and easy swap.
In theory, but unfortunately theory doesn't hold a lot of weight when it comes to swaps like this. If you've ever done such a swap, whether it be on a modern car or a street rod, you know what I'm talking about. </font>[/QUOTE]I run a street rod fuel injection shop. I know a bit about this. Just a tad.
 
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Discussion Starter #17
Originally posted by Crispix396:
ony one fully swapped the rear suspension to an IRS. Like the vets or many of the newer luxury cars. I know its work, but was wondering how feaseable it is, and how/if it helped.
I have had this discussion with others in the past, and have considered a few options.

I am currently fitting an IRS into my 53 F-100, and instead of using Jag or Vette parts, I went with an early 90's T-bird SuperCoupe rear end. It uses a 8.8" R&P, so the basic Rustang gears will work, and if you can find one the 93-98 ( I think those are the only years) Lincoln LSC used the same rearend, but with airbags. IT is an H-arm setup, like the Jag.

Downsides for B-car use. The brakes they have on these cars are downright tiny. You can upgrade however to the Mustang Cobra brakes with a little work. I still think they are little smaller than the b-car rear brakes though.

A C5 rear would be nice, but you'd have to nuke the transverse leaf and do a coil-over setup.

Other benfits of doing the IRS exist, other that potential ride improvements ( I say potential because the new Explorer rides kinda crappy compared to the Live Axle GM Trailblazer.. it's all in the tuning. The Exploder is not terrible, it's just not really much of an improvement over a live axle.) . One is exhaust routing. You have a fixed center diff, so there is a potential for simpler routing. The next is trunk packaging. You have since you no longer need jounce room for the diff, you have room to underfloor package things like spare tires.. wouldn't that be nice??

But back to the subject. Plan on jiggin up your frme, pulling the body at least once. Making sheet metal mods to your floor pans, and probably much more than $3-4k if you can't do the work yourself..

IF you do a little work, you can get the live axle to feel decent. One way is to reduce unsprung weight. The best start is to ditch the swaybar fro the axle, and mount it to the frame. YOu just pulled ~10% of the axle weight off...
I used to dislike the non-parallel 4-link, but it does have benefits for a slight rear-steer effect. The next improvement would be to ditch the full urethane rear suspensions that people run, and allow one of the links to have more freedom. I think somebody makes LCA's with rod ends in the front links, so that will reduce suspension binding. I think a panhad bar wouldn't hurt either..

Just some thoughts. Don't give up on a live axle before you drop big $$$ on a custom indy rearend..
 
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Discussion Starter #18
thanks guys... the words and advice are very intresting... I just always thought how neat it would be... Just for show and for basic driving reasons.

I agree.. for strict driving reasons, i would stick with a live axel, but for bragging reasons, i like the IRS.
 
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