C4 IRS in 80-82 frame
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C4 IRS in 80-82 frame
I finally started figuring out the C4 IRS on the 80-82 frame (picked up this Dana 36 91 vette irs but have a Dana44 which I will install instead)
I thought the C4 carrier would fit the 82 frame like a glove, well I didn't measure properly [img]images/icon_smile.gif[/img] It's off by 1/2 an inch so I need to modify the ears on the frame a tad. OR I may install carrier bushings (aluminium) with off-center holes (just machine out of round alu stock)
Not that much of a problem. The dog bones come out really nice, the bracket for that will be fairly easy too. The only thing is that the susp. is a good bit wider than the stock so w/ wider rims that means I need really big flares.
Here you see it's a tad short on this side...
when the other side is lined up....
compared to stock:
So, when I get my 12"wide rear rims I'll need even more massive flares than I thought I would. Oh well, luckily with fiberglass anything is possible. :)
I thought the C4 carrier would fit the 82 frame like a glove, well I didn't measure properly [img]images/icon_smile.gif[/img] It's off by 1/2 an inch so I need to modify the ears on the frame a tad. OR I may install carrier bushings (aluminium) with off-center holes (just machine out of round alu stock)
Not that much of a problem. The dog bones come out really nice, the bracket for that will be fairly easy too. The only thing is that the susp. is a good bit wider than the stock so w/ wider rims that means I need really big flares.
Here you see it's a tad short on this side...
when the other side is lined up....
compared to stock:
So, when I get my 12"wide rear rims I'll need even more massive flares than I thought I would. Oh well, luckily with fiberglass anything is possible. :)
Melting Slicks
Joined: Jan 2003
Posts: 2,804
Likes: 1
From: OKC Oklahoma
Re: C4 IRS in 80-82 frame (Twin_Turbo)
Looks great. What year car did that come out of? Nice to see ingenuity going on with C3's. I would be doing stuff like that if I had the room and resources. I would think that parts would be alot cheaper too. If there is that much of a difference in the width of the rear, couldn't you get the half shafts, and strut rods shortened a little? I'm anxious to see more done. Keep up the great work.
Thread Starter
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Re: C4 IRS in 80-82 frame (79VetteMike)
if you shorten the shafts or use the BB halfshafts (82 has bb shafts) the upper and lower struts have to be shortened and the dog bones won't come out where I want them, they'd be inside the frame and then the shocks won't fit
Le Mans Master
Joined: Nov 2000
Posts: 8,220
Likes: 208
Re: C4 IRS in 80-82 frame (Twin_Turbo)
if you shorten the shafts or use the BB halfshafts (82 has bb shafts) the upper and lower struts have to be shortened and the dog bones won't come out where I want them, they'd be inside the frame and then the shocks won't fit
:cheers:
Drifting
Joined: Jul 1999
Posts: 1,542
Likes: 43
From: Plano TX
Re: C4 IRS in 80-82 frame (Twin_Turbo)
This is great! I have an 80 with ZZ4 power and the front VBP transverse leaf and tubular control arms. I wanted to go with the Guldstrand kit in the rear, but very concerned about using rod ends for a car driven on the street.
I wonder if a Delrin bushing could be made to give the correct offset for the frame ears? Would be nice to go poly to reduse noise and vibration.
Looks like it will be easy to attach a mount to the new diff for the front attachment point.
If this works, it would be nice to find away to put 84 or newer brakes on the front.
Dave
I wonder if a Delrin bushing could be made to give the correct offset for the frame ears? Would be nice to go poly to reduse noise and vibration.
Looks like it will be easy to attach a mount to the new diff for the front attachment point.
If this works, it would be nice to find away to put 84 or newer brakes on the front.
Dave
Drifting
Joined: Jul 1999
Posts: 1,542
Likes: 43
From: Plano TX
Re: C4 IRS in 80-82 frame (DaveL82)
Sorry for the second post, but since the new rear is wider, maybe the later style wheels would correct the problem. Since the new suspension designs put the mounting flange closer to the outside of the wheel, this would put the wheel back into the wheel well.
This would also allow for 17 rims and better selection of tires. VBP hub adapters could be used on the front so a matched set of wheels could be used.
Dave
This would also allow for 17 rims and better selection of tires. VBP hub adapters could be used on the front so a matched set of wheels could be used.
Dave
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From: State of Confusion
Re: C4 IRS in 80-82 frame (Twin_Turbo)
Twinnie, I called Van Steel Thursday AM; their 4-color, 64-page catalog was in my P.O. Box Saturday AM! Two days from Fla to Pittsburgh, approx 1000+ (?) miles! You may just wanna call Van Steel yourself; with what you're putting together, you may find something you need! :cool: :flag American :flag Chevy Power :chevy :jester
Drifting
Joined: Jul 1999
Posts: 1,542
Likes: 43
From: Plano TX
Re: C4 IRS in 80-82 frame (Twin_Turbo)
Delrin is a little stonger than Nylon and is easy to machine. I used it to make offset bushings for MG's years ago. It is still used for control arm bushings since it has reasonable sell lubication properties and more rigged than Poly without going to steel. Maybe it or something like it would give a little more isolation from harmonics over aluminum.
Understand the wheel comments! I have yet to find a 17inch rim that would look good on my 80. Most are too retro, heavy steel, too modern or just too damn flashy. Plus my wife said I better not put highly polished or chromed rims on the car since it wouldn't look right.
Dave
Understand the wheel comments! I have yet to find a 17inch rim that would look good on my 80. Most are too retro, heavy steel, too modern or just too damn flashy. Plus my wife said I better not put highly polished or chromed rims on the car since it wouldn't look right.
Dave
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Re: C4 IRS in 80-82 frame (Glensgages)
what would van steel have that I need?? I live in the Netherlands and can get most stock C4 things here, a guy I know has a whole lot of C4 rear susp. setups (where I got this one too)
Marck
Marck
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Re: C4 IRS in 80-82 frame (DaveL82)
Delrin is a little stonger than Nylon and is easy to machine. I used it to make offset bushings for MG's years ago. It is still used for control arm bushings since it has reasonable sell lubication properties and more rigged than Poly without going to steel. Maybe it or something like it would give a little more isolation from harmonics over aluminum.
Understand the wheel comments! I have yet to find a 17inch rim that would look good on my 80. Most are too retro, heavy steel, too modern or just too damn flashy. Plus my wife said I better not put highly polished or chromed rims on the car since it wouldn't look right.
Dave
Understand the wheel comments! I have yet to find a 17inch rim that would look good on my 80. Most are too retro, heavy steel, too modern or just too damn flashy. Plus my wife said I better not put highly polished or chromed rims on the car since it wouldn't look right.
Dave
Race Director
Joined: Jan 2003
Posts: 15,176
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From: State of Confusion
Re: C4 IRS in 80-82 frame (Twin_Turbo)
what would van steel have that I need?? I live in the Netherlands and can get most stock C4 things here, a guy I know has a whole lot of C4 rear susp. setups (where I got this one too)
Marck
Marck
Team Owner
Joined: Jul 1999
Posts: 26,545
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From: Huntersville NC
I just posted about a related article in latest Hot Rod magazine. Work is done by http://www.wheeltowheel.net
Also, Paul Newman (Car Creations) does similar conversions. MJ
Also, Paul Newman (Car Creations) does similar conversions. MJ
Drifting
Joined: Feb 2002
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From: Manchester, Dead Center in the Middle of TN 25 miles to Jack Daniels,10 miles to Geo Dickle, and .8 mile from the Liquor Store at I-24 Exit 114
St. Jude Donor '05
Re: C4 IRS in 80-82 frame (Twin_Turbo)
Marck, you know that I too have been looking at an alternative rear suspension. I have a set of VanSteels OSTA's and of course the Dana 44 '80 rear end with 6 link mods ready to go in place. But I still have the same desire of going with the C-4 style 5 link.
I have often compared the '80 Dana rear I have with the C-4 5 link and the main recurring thought I have is " Why don't I just change the C-3 trailing arm to just a hub mount hooked to the 6 linkand use the two dogbones in front from a C-4 along with a rear tie rod. This allowing me to maintain the standard C-3 wheel offset?" Is there some type of alignment relationship that makes this impossible? I have not measured anything to see.
I looked at a C-4 rear under a C-3 frame system in Knoxville at EXPO last week. Many points involved were a repeat of the 6 link system I am in process of building, except for the axel hub and dog bones.
My Chasis book states that C-3s used a single T-arm to locate the axel hub fore and aft on the car and provide rear wheel toe control. They are well located by design but the rubber bushngs used from the factory allows toe deflection when power or brakes are applied.
C-4 systems use two trailing arms on each side together with a rear tie rod to effectively eliminate toe/torque problems present in C-3s.
I am not an engineer, so what am I missing? Isn't it possible to build or modify a hub mount to utilize the C-4's dual trailing arms and tie rod with our present pieces?
Herb Adams says that the ultimate independent rear suspension should use upper and lower A-arms instead of T-arms to triangulate support for the rear hubs thus allowing transmission of cornering loads to the chassis to be delt with by chassis stiffness or support.
This it seems has a requirement for a slip style axel to allow the axel to change length or Plunge with the travel of the wheel. The system in my Chassis book used upper A-arms and an offset lower A-arm, with early Olds Toronado plunge drive axels and hubs along with an '80 C-3 Dana Aluminum rear. A tie rod much like the C-4 was used across the back and a set of coil overs were mounted in front of the a-arm. This was built to go in a 427 Cobra. looked really trick.
I like the Mono Spring design front that is available. I do wish it had the pretty aluminum a-arms in the kit, but I'm sure it would raise the cost to much anyway. I think that it along with my 2002 Grand Cherokee steering conversion will suffice in front.
I know that this is all over my head, but I still wonder about the hub mount being made to use the two dog bone t-arms and accompany the 6 link. Jim
I have often compared the '80 Dana rear I have with the C-4 5 link and the main recurring thought I have is " Why don't I just change the C-3 trailing arm to just a hub mount hooked to the 6 linkand use the two dogbones in front from a C-4 along with a rear tie rod. This allowing me to maintain the standard C-3 wheel offset?" Is there some type of alignment relationship that makes this impossible? I have not measured anything to see.
I looked at a C-4 rear under a C-3 frame system in Knoxville at EXPO last week. Many points involved were a repeat of the 6 link system I am in process of building, except for the axel hub and dog bones.
My Chasis book states that C-3s used a single T-arm to locate the axel hub fore and aft on the car and provide rear wheel toe control. They are well located by design but the rubber bushngs used from the factory allows toe deflection when power or brakes are applied.
C-4 systems use two trailing arms on each side together with a rear tie rod to effectively eliminate toe/torque problems present in C-3s.
I am not an engineer, so what am I missing? Isn't it possible to build or modify a hub mount to utilize the C-4's dual trailing arms and tie rod with our present pieces?
Herb Adams says that the ultimate independent rear suspension should use upper and lower A-arms instead of T-arms to triangulate support for the rear hubs thus allowing transmission of cornering loads to the chassis to be delt with by chassis stiffness or support.
This it seems has a requirement for a slip style axel to allow the axel to change length or Plunge with the travel of the wheel. The system in my Chassis book used upper A-arms and an offset lower A-arm, with early Olds Toronado plunge drive axels and hubs along with an '80 C-3 Dana Aluminum rear. A tie rod much like the C-4 was used across the back and a set of coil overs were mounted in front of the a-arm. This was built to go in a 427 Cobra. looked really trick.
I like the Mono Spring design front that is available. I do wish it had the pretty aluminum a-arms in the kit, but I'm sure it would raise the cost to much anyway. I think that it along with my 2002 Grand Cherokee steering conversion will suffice in front.
I know that this is all over my head, but I still wonder about the hub mount being made to use the two dog bone t-arms and accompany the 6 link. Jim
Thread Starter
Race Director
Joined: Dec 1999
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Re: C4 IRS in 80-82 frame (PROSOUTH)
Marck, you know that I too have been looking at an alternative rear suspension. I have a set of VanSteels OSTA's and of course the Dana 44 '80 rear end with 6 link mods ready to go in place. But I still have the same desire of going with the C-4 style 5 link.
The C4 dana 44 is a good deal stronger than the 80-82 one. The 80-82 one has the bearing caps mounted on a cast surface, whereas the C4 is properly machined there. Also, the C4 case is a good bit stronger
I have often compared the '80 Dana rear I have with the C-4 5 link and the main recurring thought I have is " Why don't I just change the C-3 trailing arm to just a hub mount hooked to the 6 linkand use the two dogbones in front from a C-4 along with a rear tie rod. This allowing me to maintain the standard C-3 wheel offset?" Is there some type of alignment relationship that makes this impossible? I have not measured anything to see.
It wouldn't be too hard to mount a upper strut mount (center) on the 80-82 diff. There are 4 casting spots, sort of bosses, that can easily be tapped. Then a plate can be installed over them and the center link mounted on there. The 4 "bosses" don't lie on the same plane though.
I looked at a C-4 rear under a C-3 frame system in Knoxville at EXPO last week. Many points involved were a repeat of the 6 link system I am in process of building, except for the axel hub and dog bones.
My Chasis book states that C-3s used a single T-arm to locate the axel hub fore and aft on the car and provide rear wheel toe control. They are well located by design but the rubber bushngs used from the factory allows toe deflection when power or brakes are applied.
C-4 systems use two trailing arms on each side together with a rear tie rod to effectively eliminate toe/torque problems present in C-3s.
I am not an engineer, so what am I missing? Isn't it possible to build or modify a hub mount to utilize the C-4's dual trailing arms and tie rod with our present pieces?
you mean something like this (as I said above) ??
GRRR pics don't appear.. look in next post.
The upper strut mount will go on that plate, all you'll need then is to use a bracket on the TA like the other 6 links have.
Herb Adams says that the ultimate independent rear suspension should use upper and lower A-arms instead of T-arms to triangulate support for the rear hubs thus allowing transmission of cornering loads to the chassis to be delt with by chassis stiffness or support.
There were pics here of a C3 converted to something like that (it had a white frame) but it's a lot of work, the frame had to be notched to give room for the upper arm
This it seems has a requirement for a slip style axel to allow the axel to change length or Plunge with the travel of the wheel. The system in my Chassis book used upper A-arms and an offset lower A-arm, with early Olds Toronado plunge drive axels and hubs along with an '80 C-3 Dana Aluminum rear. A tie rod much like the C-4 was used across the back and a set of coil overs were mounted in front of the a-arm. This was built to go in a 427 Cobra. looked really trick.
I like the Mono Spring design front that is available. I do wish it had the pretty aluminum a-arms in the kit, but I'm sure it would raise the cost to much anyway. I think that it along with my 2002 Grand Cherokee steering conversion will suffice in front.
I know that this is all over my head, but I still wonder about the hub mount being made to use the two dog bone t-arms and accompany the 6 link. Jim
The C4 dana 44 is a good deal stronger than the 80-82 one. The 80-82 one has the bearing caps mounted on a cast surface, whereas the C4 is properly machined there. Also, the C4 case is a good bit stronger
I have often compared the '80 Dana rear I have with the C-4 5 link and the main recurring thought I have is " Why don't I just change the C-3 trailing arm to just a hub mount hooked to the 6 linkand use the two dogbones in front from a C-4 along with a rear tie rod. This allowing me to maintain the standard C-3 wheel offset?" Is there some type of alignment relationship that makes this impossible? I have not measured anything to see.
It wouldn't be too hard to mount a upper strut mount (center) on the 80-82 diff. There are 4 casting spots, sort of bosses, that can easily be tapped. Then a plate can be installed over them and the center link mounted on there. The 4 "bosses" don't lie on the same plane though.
I looked at a C-4 rear under a C-3 frame system in Knoxville at EXPO last week. Many points involved were a repeat of the 6 link system I am in process of building, except for the axel hub and dog bones.
My Chasis book states that C-3s used a single T-arm to locate the axel hub fore and aft on the car and provide rear wheel toe control. They are well located by design but the rubber bushngs used from the factory allows toe deflection when power or brakes are applied.
C-4 systems use two trailing arms on each side together with a rear tie rod to effectively eliminate toe/torque problems present in C-3s.
I am not an engineer, so what am I missing? Isn't it possible to build or modify a hub mount to utilize the C-4's dual trailing arms and tie rod with our present pieces?
you mean something like this (as I said above) ??
GRRR pics don't appear.. look in next post.
The upper strut mount will go on that plate, all you'll need then is to use a bracket on the TA like the other 6 links have.
Herb Adams says that the ultimate independent rear suspension should use upper and lower A-arms instead of T-arms to triangulate support for the rear hubs thus allowing transmission of cornering loads to the chassis to be delt with by chassis stiffness or support.
There were pics here of a C3 converted to something like that (it had a white frame) but it's a lot of work, the frame had to be notched to give room for the upper arm
This it seems has a requirement for a slip style axel to allow the axel to change length or Plunge with the travel of the wheel. The system in my Chassis book used upper A-arms and an offset lower A-arm, with early Olds Toronado plunge drive axels and hubs along with an '80 C-3 Dana Aluminum rear. A tie rod much like the C-4 was used across the back and a set of coil overs were mounted in front of the a-arm. This was built to go in a 427 Cobra. looked really trick.
I like the Mono Spring design front that is available. I do wish it had the pretty aluminum a-arms in the kit, but I'm sure it would raise the cost to much anyway. I think that it along with my 2002 Grand Cherokee steering conversion will suffice in front.
I know that this is all over my head, but I still wonder about the hub mount being made to use the two dog bone t-arms and accompany the 6 link. Jim
[Modified by Twin_Turbo, 3:23 PM 4/6/2003]
Thread Starter
Race Director
Joined: Dec 1999
Posts: 16,945
Likes: 9
Re: C4 IRS in 80-82 frame (Twin_Turbo)
This is nuts.. still not working. This image resize thing hates me and never shows my pic so here are the links: http://www.crossfire.homeip.net/twin...ntermount1.jpg
http://www.crossfire.homeip.net/twin...ntermount2.jpg
[Modified by Twin_Turbo, 3:32 PM 4/6/2003]
http://www.crossfire.homeip.net/twin...ntermount2.jpg
[Modified by Twin_Turbo, 3:32 PM 4/6/2003]
Drifting
Joined: Jul 1999
Posts: 1,542
Likes: 43
From: Plano TX
Re: C4 IRS in 80-82 frame (PROSOUTH)
Here is my 2cts:
1) the C3 hub/spindle assy is a pain to service. The C4 has a hub/bearing assy that is easy to swap out and appears to be a much cheaper part to service
2) I live in texas which requires that the parking brake work! I always have to tighten it up for the test, then back it off after the test or it will squeak after a while. C3 caliper is a very good concept except their heavy and rust. The C4 caliper has the emergency brake built in but is a floating design.
3) Using C4 parts gives you the hub and diff carrier mounting points for the toe tie rod assy and they are in an optimized location so no guessing on where to place them to eliminate toe steer if located in the wrong place.
4) C4 hub assy is lighter which is another big plus.
5) The T arm issue is worth looking into because there are a couple of options:
- The stock T arm with its single front mount and no flexible links at the hub causes two problems. One is toe steer over the movement of the hub up and down which is cause by the front mount contolling toe (bad design). The second is that the single mounting point causes the rear axle to squat under acceleration
- developing two mounts to pick up the C4 links would be optimum even if the C4 links need to be extended.
- A 3rd possiblity would be to build a triangulated T arm that would mount to the stock front location and then to the two C4 hub locations. This link would not eliminate axle squat however, but it would locate the C4 hub fore and aft and this triangulated T arm would use poly of rod ends at the C4 hub. This would allow the C4 toe link to control toe so this does solve toe steer. The front of the T arm would no longer be used to control toe.
Dave
1) the C3 hub/spindle assy is a pain to service. The C4 has a hub/bearing assy that is easy to swap out and appears to be a much cheaper part to service
2) I live in texas which requires that the parking brake work! I always have to tighten it up for the test, then back it off after the test or it will squeak after a while. C3 caliper is a very good concept except their heavy and rust. The C4 caliper has the emergency brake built in but is a floating design.
3) Using C4 parts gives you the hub and diff carrier mounting points for the toe tie rod assy and they are in an optimized location so no guessing on where to place them to eliminate toe steer if located in the wrong place.
4) C4 hub assy is lighter which is another big plus.
5) The T arm issue is worth looking into because there are a couple of options:
- The stock T arm with its single front mount and no flexible links at the hub causes two problems. One is toe steer over the movement of the hub up and down which is cause by the front mount contolling toe (bad design). The second is that the single mounting point causes the rear axle to squat under acceleration
- developing two mounts to pick up the C4 links would be optimum even if the C4 links need to be extended.
- A 3rd possiblity would be to build a triangulated T arm that would mount to the stock front location and then to the two C4 hub locations. This link would not eliminate axle squat however, but it would locate the C4 hub fore and aft and this triangulated T arm would use poly of rod ends at the C4 hub. This would allow the C4 toe link to control toe so this does solve toe steer. The front of the T arm would no longer be used to control toe.
Dave