Uneven Rear Offset

Oliver Vigil

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I recently installed new coil overs on my 2007 Mustang GT. The install went well, and I went to get the vehicle aligned. After my alignment I noticed that the rear driver's side tire protrudes about half an inch more than the passenger's rear tire from the fender. What could be the cause of this? The car is single owner and clear from any accidents. Thank you, and I appreciate your help in advance.
 

stkjock

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You need a adjustable panhard bar to reset/recenter the rear end. This is typical when u lower a car
 

Oliver Vigil

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You need a adjustable panhard bar to reset/recenter the rear end. This is typical when u lower a car
Just looked it up. Thank you so much. Do you think I should get another alignment afterwards, or would that be unnecessary?
 

Oliver Vigil

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Nope. There is nothing to align at the back end. The adjustable portion on the BMR below goes on pass side. .... and real easy to get to. Tubing is DOM. Adjustable portion is CM steel.
https://www.bmrsuspension.com/?page=products&productid=172&superpro=0


Oem phb brace is fubar....3 sided stamped steel. Below is the real deal.
https://www.bmrsuspension.com/?page=products&productid=173&superpro=0
Awesome! Thank you for the help, and I have one on the way right now :)
 

Nelson Valdes

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I have been told that anytime you lower any part of your car then an alignment is necessary.
 

stkjock

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I have been told that anytime you lower any part of your car then an alignment is necessary.
he had it aligned - adjusting the rear doesn't effect the front end or ride height
 

nfrizell

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This does illustrate how your rear suspension travels in an arc with a panhard bar. If you want to eliminate this get a watts link.

Sent from my SM-G930V using Tapatalk
 

Juice

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This does illustrate how your rear suspension travels in an arc with a panhard bar. If you want to eliminate this get a watts link.

Sent from my SM-G930V using Tapatalk
Maximum motorsports used to have an article on their sight on this. I forget how much the rear moves side to side as you go over bumps and dips, but if was minimal and not a reason to upgrade from a panhard bar.
 

Pentalab

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Maximum motorsports used to have an article on their sight on this. I forget how much the rear moves side to side as you go over bumps and dips, but if was minimal and not a reason to upgrade from a panhard bar.

Lower the rear by 1.25"...and axle now sticks out 1/2" on driver's side...what does that tell you ? I swapped from BMR adjustable PHB to whiteline watts link..and never looked back. Since I have 12" tiles in the kitchen, I simulated the PHB, and suspension going in an arc, all at full scale..using several 5' steel rulers... + giant protractor etc.

One end of phb goes to axle on driver's side. Other end of phb slopes upwards to car body...on pass side. As the suspension goes up/down.... the PHB is now either too long...or too short. On a corner, hit a bump on pass side rear, and suspension goes up, PHB is now too long, other end of phb pushes on axle on driver's side, kicking the entire axle out..... taking both rear tires with it. You only need to kick it out 1/32 - 3/16", to get that.... 'hang on for the ride' feeling... when flying around bumpy corners'.

This is where the watts link shines. Rear Suspension can go up /down, on driver's side / pass side / both sides...... and (several hundred lbs) rear car body is no longer flailing side to side. Car is more stable on bumps.
 

Vorshlag-Fair

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If you want to see in a video how much the axle moves laterally, check this out...


video: https://vorshlag.smugmug.com/Racing-Events/SCCA-Crandall-072813/i-Mz2bTZt/A

This was with the stock panhard bar on an S197 with 285mm street tires, coilovers with real spring rates, driving around in a parking lot...

DSC_9225-L.jpg


Watts Link tames a LOT of this...
 

Juice

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Lower the rear by 1.25"...and axle now sticks out 1/2" on driver's side...what does that tell you ?.

Tells me you need an adjustable panhard bar. I did not say you dont need an adjustable panhard bar.

The point I was trying to make is, according to MM, the difference in performance, and side to side movement of the axle is neglegible between a watts link vs a panhard bar.
 

Pentalab

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If you want to see in a video how much the axle moves laterally, check this out...


video: https://vorshlag.smugmug.com/Racing-Events/SCCA-Crandall-072813/i-Mz2bTZt/A

This was with the stock panhard bar on an S197 with 285mm street tires, coilovers with real spring rates, driving around in a parking lot...

DSC_9225-L.jpg


Watts Link tames a LOT of this...

Amazing video Terry. The amount of lateral movement is unreal. And that's at the top of the tire.
Toss in some bumps and it only gets worse. I also saw your other auto X video...which had the camera pointed forward...and on driver's side...(depicting top of tire). Same deal, and that setup used an aftermarket adj PHB.

The WL watts link is a straight forward setup. Mine was installed the same day as my eaton tru-trac LSD. That combo was one of my better investments, providing immediate beneficial results.
 

Pentalab

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Tells me you need an adjustable panhard bar. I did not say you dont need an adjustable panhard bar.

The point I was trying to make is, according to MM, the difference in performance, and side to side movement of the axle is neglegible between a watts link vs a panhard bar.

AFAIK, MM doesn't offer a watts link. Another auto X video, but with a watts link, will quickly dispel the naysayers.
 

Forty61

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Wasn't there already a thread on PHB vs. Watts Link? IIRC it turned into an argument.

An argument? On this forum? Never.

I’d love a Watts Link but more just to say I have one.. panhard works fine for my personal application, maybe not for others. The point stands that if the OP changed his ride height, the geometry for the factory bar is off and he needs either an adjustable or a Watts, price and what the car is used for will dictate the better option.
 

nfrizell

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Lower the rear by 1.25"...and axle now sticks out 1/2" on driver's side...what does that tell you ? I swapped from BMR adjustable PHB to whiteline watts link..and never looked back. Since I have 12" tiles in the kitchen, I simulated the PHB, and suspension going in an arc, all at full scale..using several 5' steel rulers... + giant protractor etc.

One end of phb goes to axle on driver's side. Other end of phb slopes upwards to car body...on pass side. As the suspension goes up/down.... the PHB is now either too long...or too short. On a corner, hit a bump on pass side rear, and suspension goes up, PHB is now too long, other end of phb pushes on axle on driver's side, kicking the entire axle out..... taking both rear tires with it. You only need to kick it out 1/32 - 3/16", to get that.... 'hang on for the ride' feeling... when flying around bumpy corners'.

This is where the watts link shines. Rear Suspension can go up /down, on driver's side / pass side / both sides...... and (several hundred lbs) rear car body is no longer flailing side to side. Car is more stable on bumps.
That feeling that you were talking about was the first thing I noticed going from FWD drive cars to my s197. I immediatly went to the internet thinking something was wrong with my car and found out about watts links. Not as big of a deal to me now that I know my car isn't broken, but a watts link is on my upgrade list.

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GlassTop09

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If you want to see in a video how much the axle moves laterally, check this out...


video: https://vorshlag.smugmug.com/Racing-Events/SCCA-Crandall-072813/i-Mz2bTZt/A

This was with the stock panhard bar on an S197 with 285mm street tires, coilovers with real spring rates, driving around in a parking lot...

DSC_9225-L.jpg


Watts Link tames a LOT of this...

I was doing just fine until I watched this video...……………….
:facepalm:
Now you got me kicking myself in the arse as I was gonna get a Whiteline Watts Link for my Stang (had it set up in my AM wishlist ready for me to hit the buy button & had already d'ld the Whiteline installation instructions ahead of time) after reading all the stuff about the Ford 3-link rear live axle suspension design & it's limitations & also watching some Cortex Racing videos in which the owner stated that if no other rear suspension part was changed w\ this rear end design the 1 part to change that would make the most difference in handling, whether racing or street, would be a Watts Link vs the PHB. I was gonna get 1 of the Cortex Racing units but the $1,100.00 price tag slowed me down, then I saw the Whiteline version which was very similarily designed like the Cortex Racing unit but was cheaper so was gonna go w\ that but as usual I talked myself out of getting it due to some of the same thinking I'm reading about in this thread.
I have felt the rear end of my car shifting as well when going thru turns on bumpy roads at speeds where the PHB would move the rear end off center enough while it was articulating, especially if you're still rocking the OEM springs w\ non-adjustable shocks instead of coilovers w\ adjustable shocks to set the ride height, spring rates, compression & rebound rates to control the rear end movements to hold it within the maximum arc range where the PHB will keep the rear end "centered". This would work but the ride will be like in a buck board wagon. This IS w\ a BMR adjustable PHB AND a BMR PHB brace installed as well AND have checked & rechecked the center on 2 occasions to make sure that the rear end was truly centered....which it was both times.
No shade thrown toward BMR or anyone that differs in thought or application but the science is clear & is also vetted in this regard concerning a 3-link live axle suspension design so to keep denying it is pointless. Now the issue of whether a PHB setup is good enough vs a Watts link for an individual's tastes, choices and\or goals is very viable.....for each individual to make. Well I've just made it in favor of the Watts link...….
My problem w\ this decision is that I allowed myself to gloss over what I clearly knew to be the better thing to do so in the end I'll be spending some money twice instead of once......and this video cemented that reality for me.

OTOH, I'm gonna be excited to send her thru some twisties once I do get it installed & set up!
:driver:
 
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