Ive seen a 69 w/ a 4 bar setup on it... but I was looking around for stuffs on it and came across triangulated 4 bar suspension.
http://www.progressiveautomotive.com/triangul.htm
That looks pretty sturdy imo... but was wondering if anyone knew anything about it. At the bottom of that page, they can custom make anything you want if you give the dimensions of your rear frame.

Is that triangulated 4 bar stuff strictly for full frame cars? or would it work fine w/ a subframe-sfc-rearframe 1st gen deal? Kinda figured having a rearframe,sfcs, etc would kinda make it a full frame car.. think im starting to ramble tho ill stop heheh

-Bud

 

Even with frame connectors, you don't have a "true" frame on the back.. You would have to do some reinforceing to run that setup, or install a "back half" subframe to get the strength.
What a re you planning on doing with the car? I wouldn't put a whole bunch of power to that setup with sticky tires... that looks more like a cruiser setup...

 

Planning on having it a cruiser kinda for now, but I want to fix up the suspension so that I dont have to make stuff later and tear it apart to make it hook. But... I want it to take a corner decent.. I guess at least to par as the GTA in the sig.

Ive heard a 4link wont take a corner corner for anything.. but Ive seen that 4 bar deal on Art Morrison and its a lot more spread out and parallel bars. If not this, then probably that.. just wondering if anyone has any experience w/ it all I guess.

-Bud

 

That type of 4-link would be very expensive to adapt to a unit body like a Camaro.

Stay with your leaf spring design. It can be made to handle and put power down very well.

 

Well, a 4 link can be done to handle-- but you have to make some mods from a drag 4 link. First, make the 4 link bars as far outboard as possible, it allows more roll without bind. Then, don't use the diagonal link locater - use a panhard bar located properly for roll center, not just a generic locator above the rear end-- that puts the rear end too high.

I did mine almost 10 years ago and like it-- removed the rear unibody frame and fab'd a 2x3 box tube frame from the subframe to the rear bumper; then used floater housings on the leafs to keep things from binding. At the time, I couldn't find a rear coil-over setup I liked, but may change it to QA1's and get rid of the leafs this winter. Of course I'll have to add a panhard rod or watts link.

I hope these pics post right--

http://home.attbi.com/~danieltonn/4LINK.jpg
http://home.attbi.com/~danieltonn/03.JPG

-Dan

 

Cool, Dan. The floating leaf is a neat solution. Did you have to shakle it at both ends?

If I were doing a 4-link F-body, I'd use a "Satchell-Link" rear suspension. It's 4 bars with the lowers angled and uppers straight. It has lots of advantages over most other sold axle suspensions;

Relatively low roll center, unlike most angled 4-links

Good antisquat

Decent roll steer possibilities

No panhard rod needed

All links attach far outboard: no axle housing bending loads

Lightweight links

Plenty of room for coil-overs


It's disadvantages:

It gets in the way of mufflers in front of the axle, but there's no panhard rod to interfere with behind the axle mufflers.

Upper link forward mounts may intrude slghtly into rear seat area.

Very few folks use (or know about) it.

 

The rear springs are set up pretty normal-- shackles just at the rear eye. The floater is a comp-engineerig piece that mounts the rear end to the spring, it allows it to rotate and also slide front and back on the spring. (there are blocks to keep the rear end from sliding left/right).

'Satchell link'-- could be interesting... I've never seen one in action... Tried various 3 and 4 links in oval track racing, and had good luck... I wonder if you can get the same 'hook' from a standing start as a conventional 4 link?

-Dan

 

I cant find anything on Satchell links to save my life. Still looking but havent found much of anything. Found a little info, but not much.. would rather see drawings/pics if possible, more of a visual learer I guess. Something like this is good stuff.

You were explaining that the bars are angled with the Satchell ... is it like that triangulated 4 link where they are angled horizontally? or is it vertically.. like having a 4 link but having the bars connected at lower points on the bottom bars?

-Bud

 

You're right, there's not much written about the "Satchell Link" rear suspension. Terry Satchell was a GM chassis engineer in the 60's and moved on to professional racing. I believe much of the advancement in Winston Cup front suspensions a few years ago was due to Mr. Satchell's fine work. In the mid 90's he was with Penske Racing, Inc. Recently he was with Andy Petree Racing in Winston Cup, but left to be Jack Roush's chief engineer last year. It may or may not be coincidental, but Roush's cars are doing better than ever.

I wish I knew how to post sketches. If you want to draw it yourself, start with the side view, and do the 4-bars like the bottom picture of the Comp Engrg link you posted. Maybe make the links a tad longer. You can adjust the angles to get the theoretical intersection point of the extended centerlines of the arms maybe 40 inches forward of the axle and maybe 14 inches high.

Now draw a top view: attach the upper and lower arms to the axle housing as far outboard toward the wheels as you can, just like the drag 4-link. Run the UPPER arms straight forward.

Angle the LOWER arms in at the front end about 45 degrees so that their extended centerlines meet at the driveshaft maybe 40-50 inches forward of the rear axle. Voila!

You can now see the elegance of this design:

All the loads into the axle are outboard where it is strong. The loads don't try to bend the housing. Bye Bye heavy welded-on "back brace"!

Cornering loads are taken by the angled arms, just like the angled upper arm GM suspensions and the ones in your original post, but again no bending of the axle housing. Hello thinner wall axle tubes! Hello reduced unsprung weight!

What is more complex to explain without drawings (and sometimes with) is roll center height and roll axis inclination. Both are very important for handling, and are adjustable within certain limits which are much better than the angled top 4-links. How about a roll center about axle centerline height and decent roll understeer.

As you'll see, fishing an exhaust system thru the links is a challenge, but doable.

We are working on a Satchell Link for '64-'72 A-body. Long way to go yet.

I think there is a sketch in "Chassis Engineering" by Herb Adams. Herb has lots of other good things to say. I believe both Herb and Terry came from the same GM car division in the 60's.

I'll look for more written info.

Found some:

If you want a good read on suspension geometry, chapter 17 of an engineering text "Race Car Vehicle Dynamics" by Milliken and Milliken, was written by Satchell. It's a step above the "popular press" suspension stuff, but not math heavy. The book is published by SAE International.

Try this link for a Satchell Link car:
http://www.hdrcoupe.com/html/tube.html

 

didnt even notice there was something there till I was about to post. Definitly thanks for the info

...was looking at some pics of it a little farther along from the same site, or so it looked, and saw these pics.
http://www.hdrcoupe.com/html/chassis5.html
http://www.hdrcoupe.com/html/suspension1.html

one is a 9" with some type of deal on it (Is that a Satchell?) ....and the other I cant figure out. Dunno what kinda rearend it is... but that cover looks like where the pinion support would go, but if so.. the 4 link would be backwards.. Im lost on that pic I gues

Just found something else too... X-link. Looks interesting I guess, but I dunno. 'Vanishing Point Race Cars' sell it here: http://www.vpracecars.com/index.cfm?attribute=rs_comp
about 1/2 way down the page.

-Bud

 

The one you identified correctly as a 9" rear; the other is a quick change style rear end, you are looking at the back of the rearend. There are a pair off idler gears that can be swapped out to change the gear ratio, used a lot on sprinters.

 

Yes, that a Satchell Link. The axle termination points aren't too far outboard, but the geometry is Satchell.

As far as the other pic, that looks like a quickchange. This link identifies it as a Speedway: http://www.hdrcoupe.com/html/differential.html

If you're not familiar with a QC, the input comes in from the front like a normal Hypoid, but the input shaft doesn't have the pinion as part of it. It passes under the axle to the rear of the case. Mounted above it is the pinion which drives the ring from the rear. Pick-off gears slip onto splines at the rear of the input shaft and the pinion shaft. By removing the rear cover, these gears can be swapped (in pairs) in a few minutes to "quickly change" the final drive ratio. Downside is extra weight, more parts and more friction(and heat). Oops texlurch beat me to the explanation.

None of the VPRC stuff is Satchell Link.