Watts Link or Panhard Bar...what do you think?

[D-CEL]

Clois,

I have built and driven both pan-hard and watts link axel locators. The pan-hard bar is definitely easier and cheaper to fabricate. However, there is a difference in how the car handles. The roll center on the axel side of the bar is constant. The roll center on the chassis side “floats” based on body roll. When you set up the bar, you adjust it to be parallel to the ground. In this position, the roll center is the same, when you turn the car (in the direction that causes the body to rotate about the chassis end of the bar) the body roll causes the chassis end, attachment point to dip, making it lower than the axle side. The result is different handling characteristics in left and right turns.
A watts-link has the roll center “fixed” about the center pivot point. It never changes left to right.
IMO, If you were building a combination street/track car with packaging and budget limitations. I would agree with the P-bar.
If you are going for track records, go with a Watts-link.
I don’t know what type of four link you run, but I have had excellent results with torque arms. They can really help put the power down coming out of the turns.
If your in the “buy” vs. “build” mode, I recommend Griggs Racing in Sonoma, Ca. They have a tremendous experience and a long winning history with stick axels.
http://www.griggsracing.com/

Jason

[Rich A]

As Jason said,
Watts is the way to go.
My opinion Watts is better than IRS.
When a IRS car takes a turn the body/frame will roll and since the IRS unit is mounted directly into the body/frame it also rolls.
With the weight transfer from cornering and the body/frame/IRS unit rolls, the inside tire inherently wants to raise from the ground and causes loss of traction of the inside tire.
There are several way of correcting this kind of traction loss.
1.Adding suspension travel so that the tire doesn't loose contact with the ground when cornering.
2.Removing suspension travel by lowering vehicle.
3.Adding stiffer springs so that the suspension doesn't compress as much. This reduces roll and also causing a harsher ride.
4.Adding a swaybar, This reduces roll and also causing a harsher ride and DEFEATS the independant suspension.


5 Link (3link w/Watts)
The 5 link does several things.
The Watts link keeps the axle from moving from side to side(like a panhard bar but better).
The 5 link doesn't transfer minor road imperfection into the body/frame similar to the IRS suspension.
The Watts link keeps the axle housing horizontal with the ground and centered under the vehicle.
The Watts link doesn't transfer body/frame roll to the axle housing causing traction loss like the IRS suspension.
Meaning better handling.

[Tom Kirkham]

Another option is a Mumford Link

http://www.susprog.com/images/Susp23.jpg