C5 irs question

[70 LS1]

Has anyone used a C5 IRS with a different rear end? I'm talking about using an older corvette or new GTO differential with the rest of the C5 suspension.

Thanks

[GetMore]

I'm not sure, but I think the "rear" on the C5 is a transaxle. I believe the suspension bolts to the transaxle, so it's not a simple swap.
You are talking about using the arms and the driveshafts, but fabricating everything else.

So, to answer your question, I don't think anyone has done it.

[70 LS1]

Its not really a transaxle. Its a transmission attached directly to the differential. The lower arms are supported by a cradle under the differential. The upper arms are attached to the frame rails. It looks like a fairly simple swap to change out the differential. This would allow a standard driveshaft setup instead of using the trans in the rear.

[silver69camaro]

This would allow a standard driveshaft setup instead of using the trans in the rear.

I believe 21st Century already makes an adapter for just that...

[dipren443]

I believe 21st Century already makes an adapter for just that...

That they do:

http://www.21stcenturystreetmachines...php?item=C5IRS

They only list an application for 1st gen camaros at this time, but I am sure it could be adapted to other models.

[70 LS1]

That they do:

http://www.21stcenturystreetmachines...php?item=C5IRS

They only list an application for 1st gen camaros at this time, but I am sure it could be adapted to other models.

Yeah, I talked with them. That might be an option, but I was thinking of using a different differential other than C5 like a C3 diff. Just seeing if anyone has tried it.

[novanutcase]

At one point I was thinking of using a 'stang 8.8! If you're going to use an older or different diff your going to have to modify the half shafts anyways! Like this:



John

[70 LS1]

At one point I was thinking of using a 'stang 8.8! If you're going to use an older or different diff your going to have to modify the half shafts anyways!

John

I just saw the build pics in your build up post. Do you think there would be enough room in your car to use buckets in the rear on either side of the trans?

[Karch]

At one point I was thinking of using a 'stang 8.8! If you're going to use an older or different diff your going to have to modify the half shafts anyways! Like this:



John

Nice plate...send it home?

[novanutcase]

I just saw the build pics in your build up post. Do you think there would be enough room in your car to use buckets in the rear on either side of the trans?

Yup! Even though Rodger, the owner of Ironworks, wants me to eliminate the rear seat I have insisted that we keep it. From Transaxle to rear door panel it measures 25". I figure with the tunnel and upholstery on both sides I should end up with at least 22" which is more than enough to accomodate a normal sized person!

John

[93Polo]

I believe someone was using a GTO diff on LS1tech but GTOs have had some diff problems. I would go with the Ford 8.8 if you're fabbing everything up. The factory C5 diff. IMO is not strong enough to warrant adapting into a traditional diff.

You may also want to looking into using a Nissan diff. The R230 is a ~9" ring and is supposed to be very tough. Hybribz.org would be the place to start researching those rear ends. Ls1tech has had some discussion as well.

[Jeremy]

The body shop owner where I get my work done just swapped a IRS rear from a Nissan 350 Z into his cuda. I crawled under the car and he had to weld up four mounts. It looked pretty slick.

I know he said for his application the width was spot on and the bolt pattern was already correct for a mopar. He's running a warmed over 360 with it and 18 inch tires.

[MrQuick]

...and you didn't take pictures?? we'd love to see it.

[calforniacuda]

I'm using a Ford Expedition rear differential with corvette c5 suspension on an irs. The hardest part is getting the correct upper control arm location. Mounting the diff has been straight forward and sits in the aluminum cradle ok.

[Samckitt]

At one point I was thinking of using a 'stang 8.8! If you're going to use an older or different diff your going to have to modify the half shafts anyways! Like this:



John

That is sweet. Where did you get the dims of the mount points of the control arms?

[Mr.VENGEANCE]

anyone know what 21st century is asking for those rear kits?

[Bruning Auto Design]

My dad used a Ford 9" center section from Dutchman back in 2000...

[calforniacuda]

A software program, Suspension Analyser, has the stock c5 suspension attachment points already loaded. A free sample program is offered with the data in it.

[Mr.VENGEANCE]

huh?

[novanutcase]

anyone know what 21st century is asking for those rear kits?

It's pretty pricey! I remember getting a quote from them but I don't remember what it was now. It was definitely in the thousands!

John