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LowBuckX
06-12-2009, 12:39 AM
here is my overly simplified theory. If you took an existing rear 4 link set up like the quadralink (only non triangulated one I can think of right now) removed the upper left link making the upper right link the "odd link" then move the odd link tward center but still offset and keeping the same length and mounting possitions. Would the geometry still be correct because all you did was delete 1 link in the system.....?????>>> :candle: No I wouldnt do that to a quadralink just used it as an example...

MonzaRacer
06-24-2009, 03:42 AM
Lowbuck what are you trying to do? Build a three link?

LowBuckX
06-24-2009, 04:51 AM
Nothing yet Im just planning my winter project. Cant seam to find help anymore so Im a bit confused.

Norm Peterson
06-24-2009, 05:39 AM
here is my overly simplified theory. If you took an existing rear 4 link set up like the quadralink (only non triangulated one I can think of right now) removed the upper left link making the upper right link the "odd link" then move the odd link tward center but still offset and keeping the same length and mounting possitions. Would the geometry still be correct because all you did was delete 1 link in the system.....?????>>> :candle: No I wouldnt do that to a quadralink just used it as an example...
The side view geometry would remain unchanged. You'd have an improved situation where articulation in roll is concerned, in exchange for giving up any ability to preload the suspension (for drag racing?).

You'd more or less have Billy Shope's offset 3-link, most likely with something other than 100% antisquat, and with tire loading that would likely not be completely equalized through the suspension link geometry.

Too-soft LCA bushings would probably allow a little compliance throttle steer.

Figure double the load on the (now) single upper and everything else in that load path, including whatever you need to add to attach the chassis side bracket to.


Norm

JRouche
06-24-2009, 07:43 AM
here is my overly simplified theory. If you took an existing rear 4 link set up like the quadralink (only non triangulated one I can think of right now) removed the upper left link making the upper right link the "odd link" then move the odd link tward center but still offset and keeping the same length and mounting possitions. Would the geometry still be correct because all you did was delete 1 link in the system.....?????>>> :candle: No I wouldnt do that to a quadralink just used it as an example...

Thats interesting. I have a art morrison parallel 4-link and have always considered the idea of losing one of the upper bars. JR

BillyShope
06-25-2009, 03:33 AM
For that matter, the same effect is achieved by deleting the LOWER left link, rather than the upper. But, I wouldn't do this with a normal dragrace 4link, for the increased loading will quickly result in a failure. A 3link must be purposely built from the start, with the increased loading in mind.

I believe Morrison calls that parallel arrangement a 4BAR, not a 4link. I like that arrangement for a street car, as the binding of a non-parallel 4link is eliminated. And, if you place them at proper angles asymmetrically, you can have 100% antisquat and equal rear tire loading on launch. See my site for details.

And, Norm, that's not "my" 3link. As far as I know, Jaguar was the first to use an offset link to equalize rear tire loading during acceleration. This was on their early C-Types. We had this in mind as we designed the first Ramchargers' car, the C/A.
http://www.racetec.cc/shope

silver69camaro
06-25-2009, 04:53 AM
Thats interesting. I have a art morrison parallel 4-link and have always considered the idea of losing one of the upper bars. JR

I wouldn't, the links are too short IMO.

JRouche
06-25-2009, 08:20 AM
I believe Morrison calls that parallel arrangement a 4BAR, not a 4link.

Well, no... They call it a 4-link. Cause well, thats what it is :) JR
http://artmorrison.com/layout.php?y=rearclips/rclips4links/&x=index

Here is mine before I stuffed it in the car.
https://static1.pt-content.com/images/pt/2009/05/4linkclip1-1.jpg

JRouche
06-25-2009, 08:22 AM
I wouldn't, the links are too short IMO.

No, Im not gonna. I was just "thinking" about it. Like ummm, I wounder what would happen type thinking, not like hey, Im gonna do this type thinking.. LOL My rear is DONE :) Im gonna drive it first before ANY more changes.. JR


DONE....
https://static1.pt-content.com/images/pt/2009/05/c-3.jpg

Norm Peterson
06-25-2009, 09:07 AM
I wouldn't, the links are too short IMO.
Can't be much shorter than the upper link in the S197 Mustang (about 9.1" pin to pin).

Then again, UCA length by itself might not be the only reason to keep all four longitudinal links . . .


Norm

BillyShope
06-25-2009, 09:39 AM
Well, no... They call it a 4-link. Cause well, thats what it is :) JR
http://artmorrison.com/layout.php?y=rearclips/rclips4links/&x=index

Yup. That's a 4link, all right. When you said "parallel," I thought you meant upper link parallel to lower link in side view. That's the Morrison 4bar:
http://artmorrison.com/layout.php?y=rearclips/4bar/&x=index
http://www.racetec.cc/shope

ProTouring442
06-25-2009, 12:52 PM
I'm no suspension guru, but I do know that the longer side of the axle will have quite a bit of leverage against the lower arm of the short side of the axle.

How do I know this? Look under the back of a '59-'64 Impala. Two lower links, one offset upper... add a nice first to second gear and a weakened factory lower arm mount and what happens? Well, the short side lower mount gets ripped right off of the frame! Then, you do a lot of steering to try and keep the car on the road as that loose lower link digs into the pavement and launches the back of the car one way then the other!

I needed new underwear after that!! :eek:

Shiny Side Up!
Bill

silver69camaro
06-26-2009, 08:41 AM
Can't be much shorter than the upper link in the S197 Mustang (about 9.1" pin to pin).

Norm

Yuk! I've seen those, but I imagine that's just for packaging.

Norm Peterson
07-01-2009, 04:51 AM
That, together with crash performance considerations.

It seems to work well enough up to include really hard street driving/autocross/open-tracking environments, maybe not quite so well in higher-HP wheel to wheel racing.

Sam Strano has walked away with the F Stock Solo National Championship two years running in a Shelby (not the GT500), and the Track Pack equipped 2010's are claimed to be getting 0.95 lateral g's without using R-comps.


Norm