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View Full Version : Watts link or panhard bar?


jdwill13
03-05-2007, 03:18 PM
I see a lot more cars with a panhard bar than a Watts link setup. I keep reading great things about Watts link but have yet to see it on any cars. Does anyone have Watts on their car?

wiedemab
03-05-2007, 07:24 PM
I know this company makes watts links for a fox body. I don't know much else about them.

http://www.evolutionmsport.com/

I know the typical arguments for one over the other involves the greater weight off the watts over the panhard. One advantage to a frame mounted watts link is that the rear roll center height is fixed relative to the chassis. With a panhard the roll center height changes with respect to suspension travel.

Oh and the watts link won't create any side movement in the rear axle with suspension movement - the panhard will.

I'm sure some of the suspension experts can discuss this in more detail.

With a Fox platform, I think either will help the "snap oversteer" created by the bind in the stock rear suspension. Adding either device to the stock suspension is redundant, but works. Probably the best solution is to either go to a 3-link w/ either panhard or watts, or a torque-arm with panhard or watts.

Later,

Brandon

EvolutionMotorsport
03-05-2007, 10:27 PM
Here are some pics of one of our Watts links installed on a car. This is our Vintage watts....

http://web.mac.com/jbauder/iWeb/6970clutchpedals/Post-Watt%27s.html

Thanks....Mike

James OLC
03-06-2007, 12:25 AM
The Lateral Dynamics 3-Link incorporates a Watts Link. There are several members on the board with this set up (myself included). Pictures of my install are on the OLC website at Lateral Dynamics Installation (http://www.onelapcamaro.com/build/rearsuspension.html). The Watts Link is a much better alternative than a panhard bar.

deuce_454
03-06-2007, 10:06 AM
the only timee you should considder a panhard is when 1) you are an OEM and want to save money on a mediocre handling car.. 2) if you are too mechanially inept to make/install a functioning watt 3) if you only turn left (circle track) otherwise a watt's link is the ticket.

jdwill13
03-06-2007, 01:41 PM
Thanks everyone.

Maximum Bob
03-07-2007, 12:43 PM
Not sure how the moderators are on this site, about telling people about a product that is not a sponsor yet, but here goes.

This company is helping us out on our 67CAMARO PT high school automotives project. The customer service is good, and Jim Fay is also a great guy to deal with.

That being said the web site is www.fays2.net, Ill try to attach a pic.

Silver69Camaro
03-07-2007, 02:20 PM
the only timee you should considder a panhard is when 1) you are an OEM and want to save money on a mediocre handling car.. 2) if you are too mechanially inept to make/install a functioning watt 3) if you only turn left (circle track) otherwise a watt's link is the ticket.

It sounds like I may be in the minority here, but you can have a very good handling car with a properly designed panhard bar. Doing so can make it somewhat difficult to package, to the point where the same amount of work it would take to install a watts.

Don't get me wrong, I like both, and each has their own place. But to say that it is totally inferior is disagreeable to me.

philofab
03-07-2007, 06:34 PM
It's easier to get a low roll center with a panhard but it's design causes the rear end to move in an arc through it's travel. The actual side to side movement is at most a half inch with a fair bit of travel. I've heard a few really good drivers can feel the side movement when driving hard but I've never been able to feel it.

The watts link is cooler looking and fairly simple to build but it's difficult to get the roll center as low with it (new reverse style watts links may correct this). It also keeps the rear end perfectly centered so it can coexist with a trianglated four bar and some other suspensions without binding (a proper rear suspention does not need two forms of lateral control though).

Anyone know how reverse watts links (like the fey kit above) effect roll center? I've never seen these kits before. I did see a kit for a late model car (forget which one) at the sema show that mounted the watts link above the axle on it's side. Seems like it would have a very high roll center.

TravisB
03-07-2007, 10:37 PM
It sounds like I may be in the minority here, but you can have a very good handling car with a properly designed panhard bar. Doing so can make it somewhat difficult to package, to the point where the same amount of work it would take to install a watts.

Don't get me wrong, I like both, and each has their own place. But to say that it is totally inferior is disagreeable to me.


matt I will have to strongly agree.....there are cars out there going way way WAY faster than anyone here ever thought about going with panhard bars. long low and level panhard bar can do wonders for a cars handling. Is a watts better? maybe? for every single car out there NO!

mazspeed
03-08-2007, 12:16 AM
Not sure how the moderators are on this site, about telling people about a product that is not a sponsor yet, but here goes.

This company is helping us out on our 67CAMARO PT high school automotives project. The customer service is good, and Jim Fay is also a great guy to deal with.

That being said the web site is www.fays2.net, Ill try to attach a pic.

I bought and tried the fays link, great quality piece, but if you have an aluminum cover on your rearend with a stainless tank, it will not work. Not enough clearance. In fact if you have the aluminum cover with almost any tank it's not going to work. If you have a ford 9 it should work.

Steve1968LS2
03-08-2007, 12:19 AM
I bought and tried the fays link, great quality piece, but if you have an aluminum cover on your rearend with a stainless tank, it will not work. Not enough clearance. In fact if you have the aluminum cover with almost any tank it's not going to work. If you have a ford 9 it should work.

That's a shame, he makes some nice stuff and he's a great guy.. and a racer.

Did he say if he was gonna try to work around it?

Silver69Camaro
03-08-2007, 07:55 AM
It's easier to get a low roll center with a panhard but it's design causes the rear end to move in an arc through it's travel. The actual side to side movement is at most a half inch with a fair bit of travel. I've heard a few really good drivers can feel the side movement when driving hard but I've never been able to feel it.


That's an extreme amount of lateral movement, and would be caused by a very short bar.

For example, a 30" panhard bar will exhibit about .070" of lateral movement under a 2" bump. .070"!! It will be more with bushing deflection, but that can be solved with heims. Who here really needs to worry about .070"?

MarkM66
03-08-2007, 08:49 AM
Herb Adams seems to think a Panhard bar works just as well. I'd believe that, :thumbsup: .

Marcus SC&C
03-08-2007, 11:11 AM
Typical factory Panhard bar= Fair
Well designed panhard bar= Good
Typical factory watts linkage= A little better than fair
Well designed watts linkage= Very Good

Mark SC&C

Silver69Camaro
03-08-2007, 11:45 AM
Typical factory Panhard bar= Fair
Well designed panhard bar= Good
Typical factory watts linkage= A little better than fair
Well designed watts linkage= Very Good

Mark SC&C

That pretty much sums it up.

philofab
03-08-2007, 11:52 AM
Silver69Camaro: I was to lazy to do the math on the side to side movement so I just guessed... I knew it wasn't very much. Anyone know if Lateral Dynamics will sell their billet watts link by itself without the rest of the kit? For some reason they dont make a kit for Ramblers... :)

Maximum Bob
03-08-2007, 11:54 AM
That's a shame, he makes some nice stuff and he's a great guy.. and a racer.

Did he say if he was gonna try to work around it?

Steve,

we just started working with Jim, and yes very nice guy with a long racing background.

However, I think his design started with the Mustangs, so the link lends itself more to a 9'', which we are running.

I know he would like to see more Camaro guys looking at his product, a re-design for an after market tank and rear end cover would surley have to constitute a market for it.

But you never know, it may be an easy change.

Maximum Bob
03-08-2007, 12:05 PM
Alert....

just spoke with Jim about Mazspeed's situation and he agreed, but did say it should fit with an aluminum cover.

He is going to send some pics over and I wll post them up.

As far as a re-design....Im thinking he would have to get three or four guys with the same problem or interest....tank/cover...

You would have to call him though.

Maximum Bob
03-08-2007, 12:29 PM
OK here are some pics of a 69 Camaro with a Moiser rear end cover and the Fays2 Watss link installed.

I dont know whose car this is.....it is from Canada though.

philofab
03-08-2007, 12:48 PM
What is the advantage of mounting the center crank to the chassis rather than the rear axle on a watts link?

Silver69Camaro
03-08-2007, 12:49 PM
it is from Canada though.

Then all bets are off!:D

Maximum Bob
03-08-2007, 01:34 PM
Then all bets are off!:D

LOL...I go round and round with my Canadian hockey mates all the time....they do know how to drink though.

Silver69Camaro
03-08-2007, 01:50 PM
What is the advantage of mounting the center crank to the chassis rather than the rear axle on a watts link?

Less unsprung weight and zero roll center migration.

mazspeed
03-11-2007, 01:55 PM
That's a shame, he makes some nice stuff and he's a great guy.. and a racer.

Did he say if he was gonna try to work around it?

Jim is a great guy and was great to deal with, but he didn't really say if he was going to fix it or not, but he was well aware of my problem. I would buy one again as would others if he could make it a little more compact.

mazspeed
03-11-2007, 02:00 PM
Alert....

just spoke with Jim about Mazspeed's situation and he agreed, but did say it should fit with an aluminum cover.

He is going to send some pics over and I wll post them up.

As far as a re-design....Im thinking he would have to get three or four guys with the same problem or interest....tank/cover...

You would have to call him though.

The guys over at Campbell Auto called me when it was there and showed me that it would not fit with the aluminum cover and Rick's gas tank that we have. I assume that the tank is the exact same size as the stock unit. If you have a fuel cell, you can set it back a bit too clear the al cover, but it just did not work with our setup. It was close but we needed some space to make sure it would clear, and it did not. Maybe Kevin here can also solidify what I'm saying as he knows of the problem as well. If Jim makes it a bit slimmer, I will buy it again no problem. I think if this could be fixed, this could be a very cheap soloution to a 4 link as this will keep the rear end in line and make the car handle much better.

EvolutionMotorsport
03-14-2007, 10:25 PM
I see a lot more cars with a panhard bar than a Watts link setup. I keep reading great things about Watts link but have yet to see it on any cars. Does anyone have Watts on their car?

Here is some general info you might find useful.

Watts Link/Panhard Bar:

WL: Constant Roll Center Height While Cornering
PHB: Roll Center Rises in One Direction and Falls in the Opposite Direction

WL: True Vertical Motion of Axle Thru Jounce/Rebound
PHB: Axle Travels in an Arc defined by the Length of the Panhard Bar

WL: Lateral Loads Reacted @ Both Frame Rails
PHB: Lateral Load Reacted @ One Frame Rail

Note: The constant rear roll center height, of a Watts Link System, will give the vehicle consistent and equal handling on both left and right turns. The overall benefits to the performance enthusiast include improved steering response, linearity, turn-in and overall cornering response, making the vehicle more predictable and easier to drive on all road at track surfaces.

A Watts Linkage is a lateral control device which consists of (2) horizontal links, (1) vertical link and a structural cradle. The cradle is mounted to the vehicles rear sub-frame (sprung weight) and used as a mounting location for the Watts Linkage. The vertical link or “Crank” is mounted to the center of the cradle which is designed to be at the centerline of the vehicle cross-car. The horizontal links are both mounted to the crank; one at the top and the other at the bottom. The opposite end of each link is mounted to a tower that extends from the rear axle housing. When the vehicle is at ride height, the optimum (rear view) orientation for the links is parallel to ground, with the crank positioned vertically. The optimum (plan view) orientation for the links is parallel to the rear axle tube.

The Watts Link System positively locates the rear axle, preventing it from moving side to side while cornering. With the rear axle essentially fixed in the lateral direction, there is now more real estate for larger rear tires without the worry of tire interference with the inner wheel well while cornering. The rear roll center is also lowered to be approximately equal in height to the center of the crank pivot. The rear roll center is the point where the lateral force is being transferred from the sprung weight to the unsprung weight. Lowering the rear roll center will reduce the portion of lateral weight transfer due to roll center height (a parameter which is not easy to tune) and allow the customer more freedom to tune front and rear roll couple distribution. The geometry of a Watts Link System also produces a constant rear roll center height while cornering unlike a panhard bar which has varying roll center height depending on whether you turn right or left. The constant rear roll center height, of a Watts Link System, will give the vehicle consistent and equal handling on both left and right turns. The overall benefits to the performance enthusiast include improved steering response, linearity, turn-in and overall cornering response, making the vehicle more predictable and easier to drive on all road at track surfaces.

More Notes:
While a vehicle is cornering and producing lateral force, the axles natural tendency is to move in the cross-car/lateral direction. With a Watts Link installed, as the vehicle builds lateral force, the lateral force is transmitted through the links into the crank, then into both frame rails through the cradle. Since one link is in tension and the other link is in compression, the load in each link is equal and the crank will not rotate. Since there are two links and one crank the lateral load is distributed between each of the two links and both frame rails, unlike a panhard bar which relies on one link and one frame rail to react all the lateral force. When the vehicle is not cornering, as the suspension goes into jounce and rebound, the crank travels with the body and will rotate to compensate for the vertical rotation of each link. This geometry will produce true vertical motion without any lateral component, unlike a panhard bar that will travel on an arc defined by the length of the panhard bar link.

Thanks....Mike

louie@g-machine
03-29-2007, 07:10 PM
mount the bar low, make it level, and make it as long as possible. most of our designs utilize a panhard bar that is approximately 40" long. Over the usable travel of the car we are getting about .05" of lateral movement. it is so miniscule for 99.99 percent of cars that the weight savings and reduced costs all of a sudden make the panhard bar look like a superior option.