3-link calculator

[feerocknok]

I was using this calc:

http://mysite.verizon.net/triaged/files ... 0bBETA.zip

and I guess I'm doing something wrong.

 

These are the results I got:

Anti-Squat #DIV/0! %

Roll Axis Angle 4.97 degrees ( - roll understeer, + roll oversteer)

Roll Center Height 25.26 in

Instant Center X-Axis #DIV/0! in

Instant Center Z-Axis #DIV/0! in

 

I did a pretty simple 3-link

| ||

----

but maybe it doesn't work...

 

but neither did

| /|

----

or

| \|

----

[DirtyComanche]

What type of three link is it for? I've never used it because I lack excel, only the 4-link one (on-line).

 

You'll need a panhard in there.

 

 

(Maybe this is obvious, okay, it probably is, I've never used that oen so I don't know).

 

 

Wait, the --- is the panhard, no...

 

 

Sounds more like you have either transposed digits, or have a compatibility problem with excel.

[feerocknok]

What type of three link is it for?

It's for two lowers, one upper, and a panhard with my '---' being the panhard.

Didn't think about Excel being the problem since I have 2007.

[DirtyComanche]

It's microsoft product, so it's pretty much a wonder if it actually works at all.

[feerocknok]

Yup, "divide by zero" error.

[feerocknok]

Well, all I really needed to know is if any triangulation was needed if a panhard was going to be used, and how short a link can be acceptably, to reduce on material costs and space restriction. Any thoughts?

[DirtyComanche]

Ah.

 

 

If the upper link is less than about 2/3 the length of the lowers, typically the AS will be whack. Along with the roll axis. Not to mention the pinion going all over the place (and hence your driveshaft).

 

With a panhard, no triangulation is necessary. However, it is good if you can as it helps with the roll axis.

 

 

Is this front or rear? I kinda skimmed through your thread, but didn't really read it (sorry, was getting to it).

[feerocknok]

Rear

 

Was thinking of:

Lowers:

30" long

21" from center of axle (Same as stock leaf perches)

3.5" forward from center of tube (looking sideways at the truck)

straight-forward

 

Upper:

30" long

17" from center

7.5" above center

straight-forward or closer to the pumpkin going towards the frame

 

Panhard:

3-4" of height change.

[feerocknok]

[DirtyComanche]

I don't know how well it will work. The calculator removes the doubt on things like that.

 

But, just looking at it, it should work fine. Or at least acceptable. The 3-link/panhard setup has a few problems in the rear, mostly to do with flex steer.

 

 

With a panhard, you want it as high as possibly to make the roll axis high (more stability).

[feerocknok]

With a panhard, you want it as high as possibly to make the roll axis high (more stability).

So basically, build the whole bracket on the axle with an almost direct frame mount?

[DirtyComanche]

Yes, build a large bracket on the axle, and not a drop mount on the frame.

 

 

The problem is that you run into clearance issues. It's a bit of a balancing act.

[feerocknok]

I'll have to take some more accurate measurements but I think all of my questions got covered. Thanks for the help on all of this.

Really doesn't seem like rocket science like some people make it sound.

[Oizarod115]

i read through this and it sure seems like rocket science to me. :redX:

[feerocknok]

i read through this and it sure seems like rocket science to me. :redX:

Basically just have to keep the axle under the truck with some mounts, and you only need enough to hold it there. Any more and things start binding.