Art Morrison IRS install, 67 Camaro

[David Pozzi]

I'm installing my Art Morrison IRS in my 67 Camaro.
This version uses the upgrade Strange Aluminum differential with Dana 60 internals.
Art Morrison also has a Camaro diff version.
Photos and notes to follow.

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144906
Trial fitting IRS in position
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Setting crossmember in position
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Had to cut out the rear seat area for clearance. Leave a flange that can be bent to set a filler panel into.
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View from underneath with suspension in place.
I may have to cut the floor more to clear the mufflers. This is the best area for mufflers.
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[zbugger]

Looks great Dave! I should try and head down for a visit one of these days.

[dhutton]

I've got one of these on order and I'm also planning to install a new trunk floor and minitubs. Any advice on the best way to go about this would be appreciated. I've been giving this a lot of thought but can't quite decide what would be best.

Thanks,
Don

[David Pozzi]

Allen, Come on down!
Don, I needed to decide wether to do the IRS install first, or do the Mini-Tubs. I decided to do the Mini-Tubs after, thinking the tubs would go up against the frame rails & need to be welded to them. These rails don't toe-in like stock rails so they are around 3" wider apart at the front crossmember. I was told to leave the old frame rail spot welds & flanges so there would be more "meat" to weld to but they didn't line up with the new rails except for the area of the bend at the top by the shock mounts and only on the outboard side there. I removed them everywhere else.

I'd do the trunk floor first, then the frame rails, then Mini-Tubs. I did find next to no flex once the frame rails were cut out. When I did Mary's second gen I was worried the unibody would shift around. I cut through the RH frame rail for the crossmember and the rear section dropped 3/4"! I was worried I wouldn't be able to push it back up to weld to the crossmember but it worked out fine.

Other than frame rail removal, the only cutting needed was at the rear seat pockets where the seat belt anchors are & the trunk kickup. I'll post a photo of where I cut.
You could install this suspension without removing your frame rails, but you would have to notch them out to install the crossmember, and plate the frame rails with 11 gage cold rolled steel on at least the inboard sides and bottom for at least 16" then locate and weld in the 4 cradle mounting tabs and upper shock mounts. The cradle & shock mounts weld to the frame rails.

The trunk floor will have to be cut right above the gas tank strap anchors, a flange bent upward, then a steel panel inserted around 3" tall across the trunk. I cut and bent up the floor where it slopes down, will post photos when I get it done.

[dhutton]

Thanks David.

[Auto Rod Technologies]

Nice!!!

[DJW32]

The suspension looks great!

The rear fenders look ridiculous(good ridiculous)
Keep the pics coming.

[Cdog]

Looks Awesome! We’re glad to see you guy’s are in the Art Morrison family. Re affirms Jack and I are on to something here. :cheers:

I cut my tubs out, trimmed the trunk and inner wheel tubs prior to install the AM Tri-4 bar. Jack and I got it in and set up in one day of work.

We installed the AM frame with the old crappy quarter panels on to reduce any body flex issues. Everything held together well on the frame rack.

[dhutton]

Very helpful pics. Thanks Cdog.

Don

[Cdog]

Very helpful pics. Thanks Cdog.

Don

:cheers:

[armourmark]

That's what I need...Art Morrison stuff. That IRS looks sweet. I can't wait to hear Mary's, I mean David's reviews. haha

[Bmf5150]

Very cool

[David Pozzi]

Here are more pics of the progress.

Rear view installed
Note gap into trunk area where light is shining through.
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Front view installed

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[sjaroslo]

Dang, that thing is the BEEF! I can only assume that sub-frame connectors are in your future? :-)

[David Pozzi]

Yes, I'll fab some subframe connectors. I'm trying to decide if I should attach them to the leaf spring mounting plates just ahead of the crossmember, then make filler plates to the crossmember, or to cut through the floor and weld the connectors directly to the crossmember.
There isn't going to be access room to weld to the crossmember unless I cut a huge hole in the floor.

[armourmark]

That looks like it could take anything you throw at it!

[David Pozzi]

Dana 60 by Strange, Driveshaft shop axles, 930 style CV joints, ZR1 hub bearings, Axles are rated at 1400 hp. It should hold up.

[David Pozzi]

Puzzling over how to route 3" exhaust around the fuel tank. The right side is a snap compared to the left. It looks like for a Rick's tank the lower edge should be moved rearward 1.5" to gain a little more room, the corners need to be lopped off like the DSE version. to allow room for the pipes to go around the corners.
AME ran 2.5" pipes over the round tube next to the diff, 3" can't quite make it.
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[Ron.in.SoCal]

Great project David! :cheers:

[David Pozzi]

I'm doing trunk filler panels now, then on to the Mini-Tubs.

[TheJDMan]

David,
What is the WMS to WMS measurement on that IRS? Just curious if it is similar to a stock rear end width or narrower.

[sjaroslo]

David,
What is the WMS to WMS measurement on that IRS? Just curious if it is similar to a stock rear end width or narrower.

According to the AME catalog, the IRS is available in 4 track widths: 55.5", 57.5", 59.5" and 61.5" (wheel mounting surface to surface width)
Half dozen ratios between 3.54 and 5.13
Brake options: 12.4" rotor with floating caliper, Wilwood 14.2" with W6A caliper or 14.4" with OEM Brembo caliper
Minimum whel size: 17" with 12.4" brake rotors, 18" with Wilwood brakes (only certain wheels will work)

[efs69]

You got a lot done David. It is looking great. Probably a little easier after doing Mary's.

[David Pozzi]

This was lots easier & I'm better at it now that I've done Mary's. I'm doing trunk close out panels now.

[compos mentis]

67 Camaro RS that will be faster than anything Mary owns.

David,

That part of your signature should be bigger...much, much bigger.


lol

[ChevelleNV]

67 Camaro RS that will be faster than anything Mary owns.

David,

That part of your signature should be bigger...much, much bigger.


lol
I think he's afraid Mary will see it if its any bigger :)

[David Pozzi]

I think he's afraid Mary will see it if its any bigger :)

That was my intention. I tried to sneak it in to see how long it took for Mary to notice. It took a long time!

Rod, nice tank! What do they do inside for fuel slosh?

[David Pozzi]

Trunk nearly done. Mini tubs are next.

Trunk cut.
The lower trunk floor, I bent up a flange for strength and to give me something to weld the filler piece to.
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View from underneath
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I found there would be no room for my hands to reach the cradle mount bolts, so I cut out a triangular area on each corner & will make filler panels.
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Test fitting the corner filler pieces. I Made them raised but dropping down towards the center so I could have a little extra room underneath for access to the cradle attachment nuts.
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Filler panels
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Nearly finished trunk. I pushed the front portion up to make room for the rear cradle. On Mary's 73 Camaro, I made a whole new piece but it was very difficult to get in there to weld the forward edge. This way it's still attached & less work.
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[Motown 454]

It looks great David. Very interesting install.

[silver69camaro]

David,
What is the WMS to WMS measurement on that IRS? Just curious if it is similar to a stock rear end width or narrower.

It's 59.5", so basically stock. This is mainly done for packaging reasons, as it allows the UCA to clear the frame rail well. I know some like a little more dish in the wheel, but having a little wider track width is easier on the wheel bearings and reduces bushing deflection under power.

[Eric Howell]

Great, now Mary will be even faster:banghead: Guess a lot of driving school is in my future.

Thank you for all the info and great write up. Very informative. Guess Matt did an awesome job as usual since Mary ran leaf springs forever!

[dhutton]

Any updates David?

Thanks,
Don

[dhutton]

Did a test fit of the IRS and wheels on my 69. 12 inch wheels with minitubs and I am stretching the rear quarters by a little over an inch to get a little margin. Planning on a 345 tire.

Don

[David Pozzi]

I've done the left side quarter stretch by installing a replacement "skin" panel. Working on the right side now.
108725108726

[dhutton]

I knew my post would bring you out David. Good to see your photos. Have you decided how to run the brake lines etc?

Thanks,
Don

[Rod]

i've done the left side quarter stretch by installing a replacement "skin" panel. Working on the right side now.
108725



awesome!!!!!!

[David Pozzi]

Don,
I'll probably run them down the sides, thru the crossmember, then up the rear floor with a bulkhead fitting on each side like I did on Mary's car below.

[grendel]

What rotors did you decide to run? I want to stick with the stock Brembos. Does a ZO6 rotor match the stock Camaro in rotor hat e-brake and Brembo cast in abutments?

[David Pozzi]

We run on 18" rims, so went to Baer 14" rotors & their 6R calipers. The E brake works. Morrison sells a Willwood setup for it.
The Camaro has a metric bolt circle where the Corvette hubs used are the old Chevy bolt pattern. I think the two are super close. The Corvette hubs used have a larger center register than the Camaro. I had to bore the rotors to fit. AME normally uses a Willwood kit to fit with everything modified. I'm using Baer 6R calipers and 14" rotors. Baer came up with this kit to fit the AME IRS for us, since we wanted to stick with their products. It's extra work to squeeze 14" brakes inside a 18" rim, using the 5th gen Camaro knuckles.

I may route my brake lines to in front of the fuel tank. It would allow me to remove the calipers with lines attached, hang them by wire, then drop the IRS out. The way it is on Marys car, the brake hoses must be removed, but there is less motion of the hose by following the lower forward link.

[grendel]

We run on 18" rims, so went to Baer 14" rotors & their 6R calipers. The E brake works. Morrison sells a Willwood setup for it.
The Camaro has a metric bolt circle where the Corvette hubs used are the old Chevy bolt pattern. I think the two are super close.

I may route my brake lines to in front of the fuel tank. It would allow me to remove the calipers with lines attached, hang them by wire, then drop the IRS out. The way it is on Marys car, the brake hoses must be removed.

What radial mount did you use to put the Baer 6R onto the GM 5th gen Camaro rear knuckle? I talked with Baer and the only kit that have uses a 15.5" rotor. I'd like to stay stock 14.4 Camaro with the internal e-brake.

I can confirm that the bolt patterns are super close. I put Corvette wheels on the Camaro hub, since the Camaro rotors would not fit over the Z06 hub.

[David Pozzi]

Baer did a conversion for us to convert to 14" rotors. The 15" rotors MAY clear 18" rims depending on the MFR of the rim. We possibly could have been OK but it was too close to risk it. Their conversion may not be a listed kit yet but they can do it. Have them look up what they did for Mary.
Willwood has rear brakes that work, that is what Art Morrison sells.

Here are the Baer 14" brakes on Mary's Camaro, Mary took more and better photos, I'll see if she has one of the brackets. I had to cut a flat on the GM cast aluminum knuckle but Morrison now does it for you. Mary's was the first customer unit, mine was the second.

https://static1.pt-content.com/images/noimg.gif (http://s117.photobucket.com/user/davidpozzi/media/73%20Camaro/IMG_0292_zpsrewu72yw.jpg.html)
https://static1.pt-content.com/images/noimg.gif (http://s117.photobucket.com/user/davidpozzi/media/73%20Camaro/imagejpg1_zps004786b5.jpg.html)

[dhutton]

Time to bump this up for some updates from David. My install is complete except the e-brake cables. I plan to use an E-Stopp. I am running Brembo brakes off a 5th gen ZL1 so I had to swap the hubs. Here's a couple of pics. The exhaust is also done, I ran 2.5 inch under the center section.

Don

[ChevelleNV]

Time to bump this up for some updates from David. My install is complete except the e-brake cables. I plan to use an E-Stopp. I am running Brembo brakes off a 5th gen ZL1 so I had to swap the hubs. Here's a couple of pics. The exhaust is also done, I ran 2.5 inch under the center section.

Don

Nice looking setup Don, who did the driveshaft and adapters? I need to get a drive shaft for my Chevelle and I am gonna need the same adaptors

[dhutton]

Nice looking setup Don, who did the driveshaft and adapters? I need to get a drive shaft for my Chevelle and I am gonna need the same adaptors

The Driveshaft Shop. Nice guy, easy to work with.

Don

[Chad-1stGen]

Cool install David and Don!

[icemanrd19]

what lugnuts are those?


Baer did a conversion for us to convert to 14" rotors. The 15" rotors MAY clear 18" rims depending on the MFR of the rim. We possibly could have been OK but it was too close to risk it. Their conversion may not be a listed kit yet but they can do it. Have them look up what they did for Mary.
Willwood has rear brakes that work, that is what Art Morrison sells.

Here are the Baer 14" brakes on Mary's Camaro, Mary took more and better photos, I'll see if she has one of the brackets. I had to cut a flat on the GM cast aluminum knuckle but Morrison now does it for you. Mary's was the first customer unit, mine was the second.

https://static1.pt-content.com/images/noimg.gif (http://s117.photobucket.com/user/davidpozzi/media/73%20Camaro/IMG_0292_zpsrewu72yw.jpg.html)
https://static1.pt-content.com/images/noimg.gif (http://s117.photobucket.com/user/davidpozzi/media/73%20Camaro/imagejpg1_zps004786b5.jpg.html)

[David Pozzi]

They are Summit brand. They are 4 to a package. 115778

[dhutton]

They are Summit brand. I'll look for a part number.

What, no updates? I need to see how you routed the e-brake cables etc. I've used your build to help me get through the rest of the install, especially the floor and trunk mods.

I have purchased similar lug nuts on ebay. Just search for the size you need, they are usually one of the lower cost options.

Don

[lowrider]

Looking Good!!!

[David Pozzi]

We didn't hook up the E brake cables on Marys car. On mine, I may run them but don't have the brakes yet. If anyone contacts Baer for IRS brakes, they have it worked out, just tell them you want the same as Mary has. Her's are 14" with the R series calipers.

[David Pozzi]

Another note on something we have been dealing with. We loctited all the CV joint bolts and marked the heads with paint dabs. The inner left hand joint had a little more grease inside and we didn't get it all out of the threads the first time. Several bolts came loose on us on that joint only but we caught them in time. I cleaned the threads with carb cleaner and blew them dry and they are holding now. Just make sure you have everything clean when you apply the Loctite.

[gio75camaro]

David this is an awesome thread! I loved reading about the IRS in Mary's car and I can't wait to see yours come together!

[David Pozzi]

Thanks, I need to start a thread on my 67 build some time. It's been going pretty slowly but coming along. Nothing fancy, but hopefully it will be fast.

[gio75camaro]

Knowing the Pozzi reputation, I think fast might be an understatement David!! Hahaha

[dhutton]

Another note on something we have been dealing with. We loctited all the CV joint bolts and marked the heads with paint dabs. The inner left hand joint had a little more grease inside and we didn't get it all out of the threads the first time. Several bolts came loose on us on that joint only but we caught them in time. I cleaned the threads with carb cleaner and blew them dry and they are holding now. Just make sure you have everything clean when you apply the Loctite.

Mine came fully assembled with the CV boots installed etc. Do I need to remove the boots and check all the bolts?

Thanks again for your help David. You have saved my bacon quite a few times on this installation.

Don

[David Pozzi]

I didn't pull the boots, I figure they are packed with grease. I pulled the CV bolts, washed out the threads on the flange with brake cleaner spray. I used red loctite and had good luck on all but but the left side of the diff , it kept working loose on us. Finally I bought stage 8 locking fasteners. They have a tab that sticks out to prevent turning, and a snap ring holds the tab. I glass beaded the threads so the loctite would grab them better, they come Nickel plated. No more problems. I only used them on the LH side of the diff.

You must Torque and loctite EVERY bolt, including the steering link stud to the aluminum knuckle assy. Art Morrison does not torque them to final because they figure you will dissassemble to powder coat or paint them.

Another tip on the lug bolt pattern. Art Morrison uses a Corvette ZR1 hub, which has a std old style 4 3/4" bolt circle. The std late model Camaro hub uses a metric bolt circle so any late Camaro brakes you use would need to have the bolt pattern modified to fit. They are very close, but different. Also the center hole register is larger on the Corvette unit bearing.

Also you need to be careful if you change your camber setting. Changing camber will change the rear caster. Rear caster is the "clocking" of the rear knuckle looking at the side of the car. If rear Caster changes, the height of the toe links change and that greatly affects rear toe change as the suspension moves. The latest version of the installation manual should have the required caster specs. Measure by placing a degree finder against the caliper mounting bolts, or the underside of the calipers if you can find a flat area. Ask AME for a caster spec for the camber you are using.

[grendel]

I didn't pull the boots, I figure they are packed with grease. I pulled the CV bolts, washed out the threads on the flange with brake cleaner spray. I used red loctite and had good luck on all but but the left side of the diff , it kept working loose on us. Finally I bought stage 8 locking fasteners. They have a tab that sticks out to prevent turning, and a snap ring holds the tab. I glass beaded the threads so the loctite would grab them better, they come Nickel plated. No more problems. I only used them on the LH side of the diff.

You must Torque and loctite EVERY bolt, including the steering link stud to the aluminum knuckle assy. Art Morrison does not torque them to final because they figure you will dissassemble to powder coat or paint them.

Another tip on the lug bolt pattern. Art Morrison uses a Corvette ZR1 hub, which has a std old style 4 3/4" bolt circle. The std late model Camaro hub uses a metric bolt circle so any late Camaro brakes you use would need to have the bolt pattern modified to fit. They are very close, but different. Also the center hole register is larger on the Corvette unit bearing.

Looks like this:

http://www.lateral-g.net/forums/attachment.php4?attachmentid=57642&stc=1&d=1457578298

The rotor brake holes are larger, since the Camaro uses a 14MM stud and the ZL1 uses a 12mm stud. If you carefully open up the rotor hub register, you can make the rotor hub centric, which has no affect on the balance of the assembly. Kore3 made my radial brackets to put a Baer caliper on the Camaro 14.4" rotor.

[grendel]

Oh and the Corvette is 5 on 120mm and the Camaro is 5 on 120.4MM (or something like that).

[andrewb70]

The Camaro is 5x120 and the Corvette is 5x4.75"

Andrew

[grendel]

The Camaro is 5x120 and the Corvette is 5x4.75"

Andrew

Yeah, I am dyslexic.

4.75" in MM is 120.65MM = Corvette pattern, with 12MM wheel studs.

Camaro is 120MM with 14MM wheel studs.

[David Pozzi]

Another note, we installed Stage8 locking tab bolts on the left hand differential CV joint. I cleaned it AGAIN and even glass beaded the threads for more "tooth" for the loctite to grab. The Stage 8 bolts are nickel plated and so smooth i was worried the loctite wouldn't grip them well. Mary has run a year with them and they are staying tight. You need to use a very high quality 12point socket to torque them due to the small head size. I broke mine, bought a snap on replacement.

[KB Camaro]

Sorry to resurrect such an old thread, I have a 67 and just picked up my AME IRS and wanted to ask if you have an pics of how you routed the exhaust? Did you go with 3inch all the way through?

[David Pozzi]

Haven't done the exhaust yet on my 67. I mocked up some tail pipes in various routes trying to figure a way to do it. The right side has a bit more room, the left side is very tight.
AME on their 1969 test car ran 2.5" pipes through the cradle, over the lower control arms & cradle support tube.
Ill see if I can find my pics and post them.

[David Pozzi]

These are all 3" tube. I tried oval tube on the left side. Running oval tube 3" is close to making it. 2.5" oval would be easier to fit. The left side is the tough side. 167527167528167529167530

[David Pozzi]

This is the AME test car. 2.5" I believe. although looking at the photo, it looks smaller than 2.5". 167531

[dhutton]

I ran 2.5” under on mine. Tucks in pretty good and it looks good from behind.

Don

[TheBandit]

Hi David - any updates on this project?

[David Pozzi]

Not much. I was working along on it, then the doctor found a large Basil Cell Carcinoma on my forehead. I had a chunk of my forehead skin removed about the diameter of a soda can top & had to have reconstructive surgery where they lifted a big chunk of my scalp and moved things around to cover the hole. My head had more stitches than a baseball. It worked out OK and all but I stopped working on the car and although I have gotten some other non-car projects done. I've not been very motivated to keep working on it. I WILL get back to it!

Mary and I started riding Motorcycles during COVID and it's been a huge distraction, but good for my state of mind, very relaxing. Our local autocross site closed and we have to tow 100 miles one way to race now. Mary sold her Camaro to a guy in San Jose, she wasn't running it and decided it was time to let it go. She has a 2009 Corvette ZO6 now.

[TheBandit]

Wow David that's quite an ordeal! I am glad you are (hopefully) recovering okay. That's a large graft to contend with and I imagine quite painful. I'm also sorry to hear you lost your local autocross site - that doesn't help much for motivation if you don't have a nearby playground. I can relate - we lost our local Camarillo site a few years ago and the 100+mile drive to the nearest sites is a disincentive. Your Camaro was on a great trajectory though. Is there anything we can do to help motivate you? Need a hand dusting off the project?

[David Pozzi]

I’m all healed up & even got feeling back on my scalp & forehead. I was in surgery over four hours. No grafts, they cut my scalp side to side over the top & moved it around in a clever way, pulled my right forehead to the left to close the surgery site. hard to explain it… LOTS of stitches! But not much pain since a lot of nerves were cut. I’ll hopefully get back to working on my Camaro later this year. I’m thinking of running some track days at Laguna Seca with it since it’s closer & I can get a lot more seat time than Autocrossing.

Here’s a pic of my Motorcycle 2003 Honda ST1300
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[TheBandit]

Laguna Seca will be a ton of fun in that car. I do hope you get up there. Maybe a day in Mary's 'vette would reignite interest on the Camaro. I find it hard to stay motivated on giant projects, but seeking reinvigoration & working down a list of essentials-only has gotten me back on the road a few times. Your motorcycle looks like a great cruiser. Stay safe out there and enjoy!