This was brought up in another thread. There is a shop out there that makes IRS install kits for earlier Fbodies who is interested in doing so for the 4th gen cars. They wanted to find out if people are actually interested in this kit. The C4 IRS does not wheel hop like the Cobras do, also you can run true dual exhaust with this kit installed as the exhaust pipes pass under the rear gear case. Here are some pics of a first gen install:







Here you can see the area under the C4 IRS gear box where the dual exhaust would run:

 

I wish I had the money.

 

I wish they made a kit sooner, I just sold my C4 that had $$$$ 6061 alloy half shafts (from a Pro Stock Truck) and beefed Dana 44 with 3.73 gears, spicer U joints, etc. I really wanted to do that with my 2000 Camaro, but thats how it goes.

 

Quote from a member of my local car club.

 

He's off on that. For one thing, this does not use a torque arm. The torque arm mounts on the C4 IRS mount to a cross brace that goes between the frame rails. The gear box brace ties in to mounts welded onto the frame rails. In the picture below the long piece on the top is where the TA mounts on the rear attach. The trailing arms attach to the two pieces in the center of the picture. I'm not sure what he is talking about with dog bones and cutting into the rear seat area. Also the Panhard bar mount is behind the rear end with enough clearance.






The shop that would be making the mounting kits has a 4th gen local to them and they want to find out if we would have any interest in this. They will do the R&D on it.

 

So I signed up just to respond...

Anyway, I understand the first gen setup, but the 4th gen is FAR from the first gen. The 3rd and 4th are very close... At any rate, rather than try to explain all the steps involved, take a look at this.

That 3rd gen is local to me and I've seen every part of the underside of it and done some planning already for my swap. The welds could be better, but not a bad job for being done in a home garage. Everything in my setup will be tig'd together.

You might get away with replacing the torque arm with that kit, but you will still have a problem fitting the dog bone mounts into place. The PHR is a lot closer to the rear than you think. With the batwing located behind the dana 44 rear (which is a longer case, i might add), the PHR mounts definitely do get in the way.

BTW, I'd be happy to donate my car for their guinea pig -- it'll save me a lot of work.

 

Where are you located at?

 

I'm in the St. Louis, MO area.

 

I'm interested, depending on $$$$.

 

I've been looking for a shop to do this to my '02 t/a. Has anybody gotten any where with this.

These are the shops I've contacted:
http://www.seattlestreetrods.com/index.htm
http://www.rickroush.com/
http://www.waynedue.com/web/Products/irs.html

 

not me... plans changed when i picked up a moser 9" for $1200

 

I'm still interested, i don't drag race...just street. It'd be unique to have an modern f-body with an IRS, but only with a sway bar. Don't want it to handle like a pig.

 

just go slightly stiffer in the rear spring and put a bigger front sway bar on... a sway bar in the rear (and going up in rear bar size or spring rate) actually frees up the rear end of the car.

By planting the front end with a bigger bar, you'll make up for the lack of a rear bar. The car will corner better this way than one with stock sized bars in both locations.

 

So I guess this never happened, anyone know which company this was?

 

As far as I know there are only 2 or 3 cars out there that have done this swap. The shop I work for, Zeus Performance, and the owner of this SOM 94 Formula is the only one that I have seen that the car has not been back-halved.

This is the car:







This is the underside of the car.


















Jay, co-ower of Zeus Performance, designed this setup by flipping a 3rd gen on it's roof and taking measurements. As you know, the 3rd gen rear ends are basically the same as our 4th gen rear ends and therefore the measurements are almost identical. After putting this car through it's paces and turns personally I can honestly say it is amazing. I will be doing this swap to my car in the near future...if the budget allows.

The entire rear end has been ceramic coated and powder coated for durability. To create a more rigid sub frame, a cross brace was implemented above the rear end housing. Also, custom sway bar mounts were fabricated to allow the use of the factory C4 sway bar.

The exhaust was run using a set of flex pipes to allow movement with the body. The rear sections of the exhaust were hung from the rear end housing to create a beautiful symmetrical view from the rear.

 

wow that looks nice, almost like it belongs in there.

 

Very nice, I have seen some pics of this car before, any plans for a kit?

 

Much appreciated my friend. It was a good deal of work, but definitely worth it in the end.


As of now, we have no plans to mass reproduce the setup, however we would be very willing to re-fabricate the setup in a customers car if someone wanted it done. We actually have had a few people ask about it and pricing but as everyone knows there are a lot of tire kickers out there, so no one has been serious enough yet for us to be able to do it again.

The car was featured in the Pit Stop section of Hot Rod Magazine in July 2008. Here's a link to more pictures of the install. Jay's 94 Formula IRS Swap

 

damn, i would love to have have this setup

 

Uh, I have been wanting this since I got my first 3rd gen. And seeing how the rear of the 4th it just like the 3rd, I would certainly be interested. Maybe I'll do it to my 3rd and 4th gen LOL

Did anything ever pan out from this, I remember seeing a 3rd gen with it done a few years back but it was...extensively hacked up.