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Discussion Starter #1
I have my first ever track day coming up on 8/24, and have been busy dusting the cob webs off my 67 getting it ready and sorted. My car has always felt a bit unsettled/wallowy the faster I went and the harder I pushed it through a corner. After some late night reading I decided to venture building and installing a panhard bar. My employer has a metal fabrication shop that had some downtime this week so I decided to take advantage :).

We just finished installing the bar this afternoon and after the first test drive it made noticeable changes in how the car responds (for the better, mostly). When I initiate a turn the car just turns; there is no wallowing and waiting for the rear end to settle into the turn. The other noticeable change was that the front end now pushes, where as prior to the panhard I had to be delicate with the throttle to keep the *** end from coming around on me. So my question is, shall I tweak the bar to force a little bit of oversteer like I am used to or relearn to drive it with more gas pedal? If I tweak the bar, what movements do what with regards to changing handling characteristics (I have up/down adjustment on both ends and can adjust bar length slightly as well)? I currently have the bar set level with the rear axle, right at the axle centerline. My "assistant" who was welding and fabbing everything has past experience dirt track racing, and kept questioning why I was setting the bar level vs angled (from my reading if you are going round and round in circles its best to load one tire more than the other).

Any assistance that you can provide with panhard bar setup, what works on your Mustang, what you have seen/heard from others, etc, would be appreciated!
 

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That's a Watts Link..... not a Panhard Bar.

Just a start. Don't know that I want to tune your car though.
I see a number of interesting details. (washers under u-bolts, lowering blocks and
some kind of link with a rod end under the leaf)
No doubt it's real interesting to drive.

ex-Global West GM
1991-1995
 

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The standard in race school and how many of us learned to race (or track day) is to get the car as generic and neutral as you can when first learning. Ditch the non stock items. Factory ride height, camber and caster and corner weights. You aren't learning to tune a car at this point. You are learning how to tune the driver. :grin2: Even a poor handling car will be faster than a first time track session driver. Once you get a handle on how to drive a neutral car you can start working on tuning your car. The goal is to learn to jump into any car with a neutral setup and get as much out of it as the car is possible of giving.

Don't be this guy... :surprise:>:)

 

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Discussion Starter #7
That's a Watts Link..... not a Panhard Bar.

Just a start. Don't know that I want to tune your car though.
I see a number of interesting details. (washers under u-bolts, lowering blocks and
some kind of link with a rod end under the leaf)
No doubt it's real interesting to drive.

ex-Global West GM
1991-1995
Last I checked a watts link uses two rods and a wobbly bit in the middle...

Regarding the washers, the traction bar brackets would not sit flush on the shock plates, hence the washers. I should probably just weld brackets directly to the shock plates and ditch the extra bracket.

I have also installed the wedges to correct the pinion angle (lowering is a side effect).

And lastly the traction bars, well, there job is obvious and they have performed well the past 10+ years (they replaced the Shelby style under ride bar after snapping a bracket off due to the poor design).

There is a lot of lip stick on this pig 😉
 

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Last I checked a watts link uses two rods and a wobbly bit in the middle...

Regarding the washers, the traction bar brackets would not sit flush on the shock plates, hence the washers. I should probably just weld brackets directly to the shock plates and ditch the extra bracket.

I have also installed the wedges to correct the pinion angle (lowering is a side effect).

And lastly the traction bars, well, there job is obvious and they have performed well the past 10+ years (they replaced the Shelby style under ride bar after snapping a bracket off due to the poor design).

There is a lot of lip stick on this pig 😉
I was thinking it was an incomplete photo of a watts...... sorry about that. Should have looked closer.
I'm still not critiquing your stuff as I don't agree with a bunch of it.
(total guess.... the Traction Master bracket probably broke due to conflicting angles,
but I'll let someone else provide you advice)

ex-Global West GM
1991-1995
 

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Discussion Starter #10
(total guess.... the Traction Master bracket probably broke due to conflicting angles,
but I'll let someone else provide you advice)

ex-Global West GM
1991-1995
Yes, the traction masters angle of movement doesn’t match the leaf spring, plus, the stock front bracket is only single shear... all of this combined resulted in overly stiff rear suspension and eventually a broken bracket.
 

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Discussion Starter #11
The standard in race school and how many of us learned to race (or track day) is to get the car as generic and neutral as you can when first learning. Ditch the non stock items. Factory ride height, camber and caster and corner weights. You aren't learning to tune a car at this point. You are learning how to tune the driver. <img src="http://forums.vintage-mustang.com/images/Vintage-Mustang_2015/smilies/tango_face_grin.png" border="0" alt="" title="Big Grin" class="inlineimg" /> Even a poor handling car will be faster than a first time track session driver. Once you get a handle on how to drive a neutral car you can start working on tuning your car. The goal is to learn to jump into any car with a neutral setup and get as much out of it as the car is possible of giving.

Don't be this guy... <img src="http://forums.vintage-mustang.com/images/Vintage-Mustang_2015/smilies/tango_face_surprise.png" border="0" alt="" title="EEK! Surprise!" class="inlineimg" /><img src="http://forums.vintage-mustang.com/images/Vintage-Mustang_2015/smilies/tango_face_devil.png" border="0" alt="" title="Devil" class="inlineimg" />

Ha! That video made me laugh!

I was leaning towards just leaving it be for now, for the exact reason that my abilities (or rather, lack there of 🤪) are well behind what the car is capable of. The good part of this first track day is that there is a classroom portion, parking lot drills, and then track time, all with instructors watching close by. This is a new requirement now for folks to run at Sonoma Raceway (aka Sears Point, aka Infineon) these days if you don’t have prior track experience. I’ve heard and read nothing but good reviews about the program and am really looking forward to it!
 

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It's best to have the car push or under-steer if you don't have much track experience, and if you've never had the car on track. What feels neutral on the street will be too loose in high speed corners. As you gain experience you can "free up" the car (add oversteer) if you feel the need.
 

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The thinking behind having a neutral setup to start is so you know what the car does on its own. It gives you a baseline from which to work. You learn control of the car by learning braking and entry points along with using the right line around the corner. At a pro school the entry level drivers are not allowed to make or suggest changes to the car. It wasn't until I was in the advanced racing portion of the program I was allowed to ask for changes. A DE program is not going to be that deep but by applying an arbitrary setup changes prior to your first sessions isn't going to help the driver learn proper techniques.
 

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Discussion Starter #14
Thanks for that info, all that makes sense.

Now, when the time comes to adjust the Panhard bar, what bar movements translate to inducing more oversteer, more understeer, loading one tire more than the other, etc? I’m curious how the vehicles handling characteristics are affected by the position and angle of the bar (generally speaking).
 

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Well have fun with my setup folks! The only thing I found wrong with daveoxide's pictures was the exhaust! With my asthma, emphysema, COPD, or whatever the endless string of "medical professionals" are calling it this week I wouldn't last 1 minute in his car!

Maybe we should call him davecarbonmonixide?
 

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Almost the same, but no wedges and I have a set of slide a link traction bars (no binding the way the under rider bars bind, at least so Ive come to understand)

The higher the bar, the higher the roll center. Gives a stiffer feel to the rear.


Sent from the interwebs
 

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That's a panhard bar. I'm a little worried about the strength of the end brackets and if they're able to withstand a tight high speed turn. If one of those bends or breaks you're gonna snap turn with bad results. The basic theory of a panhard or watts setup is described very well by Ron Sutton at protouring.com. think of it this way, with a stock rear suspension the body wants to naturally roll left/right as you drive around a corner. The panhard or watts controls that body roll; the higher the bar the less the body roll, the lower the more. The higher the bar it tightens up the rear. Itll feel real good up to a point, then suddenly wants to break loose and come around on you. You want to find the point where you're optimizing traction without breaking loose. Your suspension quality, body weight, tires, all play into this. Level bar is great for left/right road racing, angled bar is great for roundy rounds; the left turn guys.
 

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moving it up loosens the rear end up, moving it down tightens it up....

I would lower the bar one inch or so... and run half the track day or even the full track day before deciding if it needs to be higher at all.

it's a fairly easy thing to adjust between sessions and everyone else is right that understeering is safer.

There are likely a lot of other things you are going to want to play with, upgrade and fix before you mess with roll center once you figure out what the car is really doing on the track.

What's your front suspension setup and alignment settings and what tires are you on?

What are you running for brakes and fluid?
 

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Discussion Starter #19
Thanks for the feedback and pics everyone!

What's your front suspension setup and alignment settings and what tires are you on?

What are you running for brakes and fluid?
Front suspension is “620” springs, Shelby/Arning drop, boxed lower arms, heimed strut rods, bump steer drop thingies, and power rack and pinion. I can’t tell you numbers for caster and camber other than enough caster to get good steering feel and visually noticeable amount of negative camber 😋. Toe I just set and that’s 1/8” toe in. Tires are just regular street tires, 245/50R16 Cooper RS3 (I think) all around. Front brakes are Granada (i’m contemplating a front brake upgrade if I kill the Granada’s) with cooling ducts and the rear is drum from the mid 90’s explorer my axle came from. Brake fluid is fresh dot 4 (just replaced my master cylinder and rear wheel cylinders as I was going over the car).
 
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