Thread: Rearend links- 4 link, 3 link, parellel, angled???

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No, I mean the holes on the rear end.

Originally Posted by maddddog

No, I mean the holes on the rear end.

Depends on which configuration you're goin' with. Are you gonna use short links (13" like you figured) or longer links like the 24" jobs I showed or a rear arrangement like Jerry Clayton suggested?

Thanks for the link, Richard!!!! Lots of neat stuff--and good ideas for a cheapskate like me!!!!! Doubt my drafting skills would justify 400 bucks---but I think I can make do with some aluminum pieces I have in the garage.... My drafting is far from technically correct, I'm sure, but it works for me, guess that's all that counts, huh???

I just really like the idea of getting the whole chassis plotted out at 1/2 scale and being able to sit back, drink coffee and analyze things!!!! With the price of materials these days, being able to get so much closer on cut and bend dimensions can easily save in $$$$ the cost of putting a big table together....

When I engineered the independent front suspension for the T, I had a door board with a big clunky German-made drafting machine bolted to the top of the door. I picked up the machine with broken scales for cheap at a yard sale, but you could still buy scales for it. Could have done the same thing with a good 4-ft steel scale, 1-ft scale and a T-square. I had some stuff left over from earlier times like a clear plastic degree wheel and some good compasses, but it was nothing expensive.

After I got the frame, crossmember and rack located on the paper, I cut out some "paper doll" tie rods, spindles and control arms from thick, solid cardboard and stick-pinned 'em together. I kept changing lengths and angles until I got what I wanted. I had all the geometry figured out and knew exactly what the instant center, bump steer, camber gain, etc. would be before I ever bought the first stick of chromoly.

I would think that something like the roller camshaft bearings could be used in and fabbed pivot----they are available in various sizes

They will be carrying the weight of the vehicle so will need to be pretty robust

Originally Posted by jerry clayton

I would think that something like the roller camshaft bearings could be used in and fabbed pivot----they are available in various sizes

They will be carrying the weight of the vehicle so will need to be pretty robust

I looked at some roller bearings (not for a cam though) and they need a hardened surface to roll on. Do cam bearings have an inner race?

There is a watts linkage on the market that uses tapered roller bearings, like wheel bearings. A little big but might be a solution, what do you think?

Here is a side view at ride height.

The shock is compressed 1/3 of its travel.
4 inches of bump from this picture and the rear end hits the frame ( I am planning on 3" of travel and a rubber bumper)
1.5" of droop from this picture and the shocks are fully extended.

Techinspector, I did struggle with the geometry of the shock/bell crank thing and fully admit I am just guessing. Love to hear more.

Should I keep the bellcrank working at a 1 to 1 ratio or increase one side or the other?

Any unusual forces on the bellcrank pivot or just the weight of one corner of the vehicle?

Thanks all for contributing.

Your pictures are so large because you're uploading them at 940 x 637 pixels. You need to resize them before you post them. Cut them down to 640 x whatever before posting.

How about using the same bushing GM used on the trailing links on the 60s - 70s GTOs, Chevelles, etc.?

I would use a 1:1 ratio. Then you're not fiddling with your shock rates.

Also, you'll have to mount your shocks upside-down, won't you?

Originally Posted by Henry Rifle

Your pictures are so large because you're uploading them at 940 x 637 pixels. You need to resize them before you post them. Cut them down to 640 x whatever before posting.

How about using the same bushing GM used on the trailing links on the 60s - 70s GTOs, Chevelles, etc.?

I would use a 1:1 ratio. Then you're not fiddling with your shock rates.

Also, you'll have to mount your shocks upside-down, won't you?

I will look into the GM bushings, thanks.

Upside down? I hadnt thought about that. Why upside down, or are you messing with me?

Originally Posted by Henry Rifle

Also, you'll have to mount your shocks upside-down, won't you?

If I'm looking at the drawing right, they should still compress when the rear end housing goes up.
But, then it's Sunday & I just woke up from a nap.

pro is correct. I was off somewhere on a walkabout, apparently.

I think that the shocks should be mounted more toward 50/50 on there travel--as they compress the spring gets tighter and the bumper comes into play but on extension they will just go unimpeded to full travel and put pulling stresses on the shock parts that aren't considered----

The roller cam bearings just run on the cam journal---at that size they don't need to be hardened as they roll full 360* where as in rocker arms or U joints they ocillate back and forth

The GM bushings were used in the end of a longer link so they just twisted a few degrees in the rubber----on these rocker arms they will probably rotate 45* or more and that would twist the rubber-

A genuine suspension poly bushing for say a anti roll bar probably could be used around a 1 1/2 bar that was supported on both sides----actually, maybe you could incorporate an anti roll bar as the rocker mounting pivots

dog, you're proposing 3" bump and 3" droop? Nothing wrong with that, but the components you've drawn out won't support it. The rocker is way too short. Angles would be acute at that bump/droop. With a 1/1 ratio on the rocker, that would mean 3" from neutral on the coilover. There may be such animals available, but I don't know who would make them (6" total travel). The shock is installed at the wrong extension. When I bought my Eagles, Aldan recommended leaving 55% for bump, 45% for droop. Others have recommended 50/50.

Please list the shock dimensions so I can play with this.