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Watts Link and Rear Sway Bar ???

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I did a track weekend recently, I got to go for a ride in my instructor's car. His car was identical to mine in terms of suspension mods except for the Cortex Watts Link. My God the difference between the two. I want one now....

My question, after installing the Watts Link, do I keep the stock Boss rear sway bar or should I put on a smaller one ?? I asked my instructor what sway bar he was using and he wasn't sure. To me it looked a hair smaller than a stock Boss.
 
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Cortex actually suggests that you add the Watts Link first as part of a progressive build independent of other changes (shocks,sway bars, ect....). You could just add the Watts Link without any other changes and reap all of the benefits that the Watts Link. The biggest thing I notices was how the rear end "settled down" during bumps and transitions and just as importantly, acted the same ray in either direction. You may want to talk to Cortex to help set a base line for where the bell crank should be located given your current suspension set-up......
 
Remember we're talking street and track driven cars by novices not race cars with slicks driven by pro's. :)

I really liked how my car felt with the CorteX watts link and I ran stock sway bars front and rear.
 

captdistraction

GrumpyRacer
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to me a watts has the benefit of a adjustable roll center (outside the whiteline kit), typically has rod ends to help reduce any deflection, and I guess the left/right turning thing becomes equivalent.

That said, while my rear axle feels a lot nicer with the BMR watts hanging out under there, ultimately I'm not sure how much a difference it makes from the clock's perspective against a PHB at a similar rollcenter setting.

Since I'm a racer though, the adjust-ability is a big deal for me, in example I just sold my 25mm eibach adjustable RSB, installed a stock 18mm bar (tiny lil thing) and will raise the roll center to see if I like that setup more, as I had some push but adding more bar via adjustment just made the car a handful on corner exit.
 

Fabman

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This is it exactly: "ultimately I'm not sure how much a difference it makes from the clock's perspective against a PHB at a similar rollcenter setting."

The biggest change comes from the lower roll center.
If you had 2 identical cars, one with a properly setup panhard bar (and I mean really properly set up) and one with a watts link set at the same roll center (this is key) the vast majority of drivers couldn't tell the difference. Folks get way too concerned about the type of linkage that's used and completely disregard whats its actually doing.
 

Fabman

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I was at Texas World Speedway this past weekend. This is an extremely bumpy track. I just noticed how much smoother my instructors car was over the bumps than mine.

Remember he has the same "P" springs and OE struts/shocks as me....

Thanks....

A lower roll center aids in compliance. It has the effect of making the springs feel softer.


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Gab

Bullitthead
...one with a properly setup panhard bar (and I mean really properly set up)...

Aside from squaring up the axle, and leveling the PHB at working ride height, what else constitutes a properly set up bar? I'm new(ish) to PHB's and would like to ensure I'm doing it right.
 

Fabman

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Aside from squaring up the axle, and leveling the PHB at working ride height, what else constitutes a properly set up bar? I'm new(ish) to PHB's and would like to ensure I'm doing it right.

The bar is set parallel to the the axle and to the ground at ride height (w/driver).
Monoballs on both ends. Fully adjustable both left and right and up and down for quick and accurate roll center adjustments. NO BINDS!
Now you can accurately compare this to a watts; both chassis mounted and diff mounted.

Steeda has a suitable kit similar to what I ran on stock cars, and what I ran on mine before I went to a cortex watts:
https://www.steeda.com/steeda-adjustable-panhard-brace-bar-combo-555-2553.html


1) A chassis mounted watts will allow the roll center to rise as you apply brakes and lower when you are on the throttle. (Roll center follows the Center of gravity) This is known as "Roll center migration". Some call this a negative-others an advantage.

2) A diff mounted watts will keep the Roll Center stable, and let the center of gravity move above it. Proponents will say that since the roll axis stays constant, that this is a more stable arrangement.
Detractors will say that it is less forgiving as the moment arm between the roll center and the center of gravity is constantly changing.

3) A panhard bar is half way in between.
The roll center moves, but only half as much as a chassis mounted watts since one end is connected to the chassis and one end is connected to the diff.
Proponents will say that this is the best of both worlds, allowing the roll center to move, but only half as much as a chassis mounted watts. Its also, cheaper, simpler and lighter than either watts link arrangements.
Detractors will point out that as the diff moves the bar will follow a slight arc, shifting the axle slightly in jounce and rebound, and is therefore less stable over bumps.

All 3 methods work well if done correctly and compared using the same RC height.
What really matters is where the roll center is in relation to the center of gravity.
This is where everything happens. Then, you manage it with shocks and springs and bars and so forth. The method of attachment is secondary. As I said, all 3 methods have been used successfully. They just follow a little different strategy.
 
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Fabman

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Here you go;
This was my personal stock car and the prototype for all the cars I built after it.
Notice the panhard bar runs diagonally. The benefit was three fold.
It gave me a longer bar, moved vertically less when mounted forward in the chassis and provided clearance for the Quick Change cover so gears could be changed between rounds.
Later models I went back to a longitudinal setup and they worked just fine.
Notice how low the roll center is. This car was viciously fast.
602491_10150994698788535_981299012_n.jpg


602491_10150994698788535_981299012_n.jpg
 
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Fabman

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I'm waiting for someone to build a car with a Jacob's Ladder......j/k lol
We are probably the few old times who remember what a jacobs ladder is...!
 

Fabman

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There's always this:
 

Fabman

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Thanks for clearing that up.... I was wondering what the Biblical angle was..... Maybe I am tooo old.

The biblical angle is:
A panhard bar is a lot like Noah, it travels in an arc.
Get it? An Ark!
Hahahahahahahahah.....
Sometimes I crack myself up.


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