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Adjustable panhard bar needed for 1" drop?

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Old Aug 30, 2017 | 12:15 AM
  #1  
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From: Modesto, California
Car: 88 Firebird Formula
Engine: LO5 5.7 TBI/Ebl Flash
Transmission: 700R4
Axle/Gears: 2.73 stock rear end
Adjustable panhard bar needed for 1" drop?

Hey all so im curious, im running Eibach prokit which states 1" drop, rear really only dropped .5" if that. Anyways im looking at buying a panhard bar/rear lower control arm package and was curious what do you guys think do i need a adjustable panhard bar for Eibach prokit drop?

Thanks all
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Old Aug 30, 2017 | 06:39 AM
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Re: Adjustable panhard bar needed for 1" drop?

Look up under there and see.

It makes no sense to talk about "drop", since that implies a CHANGE from some former state which is largely unknown in most cases. In your instance of the ad copy vs reality divergence, that most likely was due to the fact that your car was ALREADY "dropped" ½" just from age and wear and sagging of the OE crap springs, so lowering it 1" FROM OE (ad copy) must have only lowered it a further ½" from its existing state (reality). People have put those springs on their car and it actually RAISED it, on account of their OE crap musta been wore out and sagging that much worse than yours.

My guess would be that if the car is now 1" below the ORIGINAL AS-MANUFACTURED OE ride height, it might benefit from lowering the Panhard bar 1". But really, 1" isn't a whole lot of change; it might be fine. There's a fair amount of tolerance in all this, so what one car needs, may not apply strictly to yours. Just look and see.
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Old Aug 30, 2017 | 09:23 AM
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Re: Adjustable panhard bar needed for 1" drop?

Ya know... Back in the day, they didn't even sell adjustable LCAs, track bars, and all the fancy "must-have" pieces you see now. So either lowered cars had terrible suspension geometry errors, or someone figured out all the boy racers go nuts for adjustable stuff.

Judging from some of the lack of logical thought, and poor modification execution seen on the forum in twenty years, I would have to imagine there are probably more cars with adjustable parts running around adjusted improperly than cars with aftermarket springs and stock length parts. But hey, it's just a hunch.
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Old Aug 30, 2017 | 10:05 AM
  #4  
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From: Modesto, California
Car: 88 Firebird Formula
Engine: LO5 5.7 TBI/Ebl Flash
Transmission: 700R4
Axle/Gears: 2.73 stock rear end
Re: Adjustable panhard bar needed for 1" drop?

Originally Posted by sofakingdom
Look up under there and see.

It makes no sense to talk about "drop", since that implies a CHANGE from some former state which is largely unknown in most cases. In your instance of the ad copy vs reality divergence, that most likely was due to the fact that your car was ALREADY "dropped" ½" just from age and wear and sagging of the OE crap springs, so lowering it 1" FROM OE (ad copy) must have only lowered it a further ½" from its existing state (reality). People have put those springs on their car and it actually RAISED it, on account of their OE crap musta been wore out and sagging that much worse than yours.

My guess would be that if the car is now 1" below the ORIGINAL AS-MANUFACTURED OE ride height, it might benefit from lowering the Panhard bar 1". But really, 1" isn't a whole lot of change; it might be fine. There's a fair amount of tolerance in all this, so what one car needs, may not apply strictly to yours. Just look and see.
Yeah know I didn't get a 1" drop. It a little at least. Hahaha agreed these cars are all very diff. So where exactly should I look? Are there any locations I can measure side by side to see if it's getting pushed and I'm in need?

Originally Posted by Drew
Ya know... Back in the day, they didn't even sell adjustable LCAs, track bars, and all the fancy "must-have" pieces you see now. So either lowered cars had terrible suspension geometry errors, or someone figured out all the boy racers go nuts for adjustable stuff.

Judging from some of the lack of logical thought, and poor modification execution seen on the forum in twenty years, I would have to imagine there are probably more cars with adjustable parts running around adjusted improperly than cars with aftermarket springs and stock length parts. But hey, it's just a hunch.
lol exactly why I was asking! I don't want to grab the adjustable if it's unneeded and I can just grab the replacement bar and be good to go.
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Old Aug 30, 2017 | 10:10 AM
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Re: Adjustable panhard bar needed for 1" drop?

If your going to buy a new bar anyways, I'd buy an adjustable. If you go through founders or umi the price difference isn't much from the non adj to adj version. That way if your rear end is off you can re centre. If your not buying a new bar like the others say it's likely not a huge deal. I'm doing the pro kit as well and opted for the founders adj. I'm in the middle of installing so can't tell you if it's worth it or not yet. Lol
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Old Aug 30, 2017 | 11:05 PM
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From: Modesto, California
Car: 88 Firebird Formula
Engine: LO5 5.7 TBI/Ebl Flash
Transmission: 700R4
Axle/Gears: 2.73 stock rear end
Re: Adjustable panhard bar needed for 1" drop?

Originally Posted by A88GTANotchback
If your going to buy a new bar anyways, I'd buy an adjustable. If you go through founders or umi the price difference isn't much from the non adj to adj version. That way if your rear end is off you can re centre. If your not buying a new bar like the others say it's likely not a huge deal. I'm doing the pro kit as well and opted for the founders adj. I'm in the middle of installing so can't tell you if it's worth it or not yet. Lol
True for Founders, but UMI the price diff is a bit larger. Still trying to decide who to go with (Founders or UMI).

Does anyone know a way to measure my rear ends side-to-side location?

Thanks all

EDIT: Ok so after reading some older posts i seen that the phb should be parallel with the rear axle tubes and that the phb bars bolts when measuring from ground with suspension loaded should not be farther than 1" apart. My passenger side is 12" from ground while my driver side is 11.5" from ground. The phb also looks very close to parallel with the rear axle tubes.

I also went back and looked at my rear end thread and noticed, as sofakingdom stated, that i am part of the group that got a raise from the eibach pro kit springs in the rear end. From what i stated i said i got a .5" raise.

My rear wheel wells from ground to top of arch measure at 28" and 28.5" inches.

Last edited by Ghettobird52; Aug 30, 2017 at 11:52 PM. Reason: adding info
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Old Aug 31, 2017 | 10:56 AM
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Re: Adjustable panhard bar needed for 1" drop?

The easiest way is to drop plumb bobs down your quarter panels and measure to the wheel lip, record the measurements and calculate the difference. It's not the most accurate but will get you very close.
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Old Aug 31, 2017 | 03:22 PM
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From: Modesto, California
Car: 88 Firebird Formula
Engine: LO5 5.7 TBI/Ebl Flash
Transmission: 700R4
Axle/Gears: 2.73 stock rear end
Re: Adjustable panhard bar needed for 1" drop?

Originally Posted by FoundersPerf
The easiest way is to drop plumb bobs down your quarter panels and measure to the wheel lip, record the measurements and calculate the difference. It's not the most accurate but will get you very close.
I'm sorry can you please elaborate a little more on this? Or any one who understands this technique please explain a little more?

Thanks again everyone!
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Old Aug 31, 2017 | 07:15 PM
  #9  
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From: Modesto, California
Car: 88 Firebird Formula
Engine: LO5 5.7 TBI/Ebl Flash
Transmission: 700R4
Axle/Gears: 2.73 stock rear end
Re: Adjustable panhard bar needed for 1" drop?

Last question to anyone who can answer it. If i go with an adjustable panhard bar, say Founders 'on car' adjustable panhard bar, lets say i end up not needing the extra length can i adjust it to stock length and keep it there?
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Old Aug 31, 2017 | 07:52 PM
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Re: Adjustable panhard bar needed for 1" drop?

Yes they will work with stock hight/length application.

The plumb bob method is to just use a long piece of string running over the car side to side and hanging down over each rear wheel. Make it as even front to back as you can. Then measure from the string to the lip if the wheel, not the tire. Then you will know how much off it is side to side and can adjust accordingly.

Now the better way would be to align the wheels and wheel base lengths with all for wheels. The sheetmetal isn't always perfectly even.
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Old Aug 31, 2017 | 07:58 PM
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From: Modesto, California
Car: 88 Firebird Formula
Engine: LO5 5.7 TBI/Ebl Flash
Transmission: 700R4
Axle/Gears: 2.73 stock rear end
Re: Adjustable panhard bar needed for 1" drop?

Originally Posted by //<86TA>\\
Yes they will work with stock hight/length application.

The plumb bob method is to just use a long piece of string running over the car side to side and hanging down over each rear wheel. Make it as even front to back as you can. Then measure from the string to the lip if the wheel, not the tire. Then you will know how much off it is side to side and can adjust accordingly.

Now the better way would be to align the wheels and wheel base lengths with all for wheels. The sheetmetal isn't always perfectly even.
OOOO ok that makes complete sense, got you!!!

On a side note I was just under the car again, rear this time lol! It def looks like im going to need lcarbs as i can see my control arms trailing downwards to the unibody.

Thanks again everyone for info!
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Old Aug 31, 2017 | 09:21 PM
  #12  
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From: Modesto, California
Car: 88 Firebird Formula
Engine: LO5 5.7 TBI/Ebl Flash
Transmission: 700R4
Axle/Gears: 2.73 stock rear end
Re: Adjustable panhard bar needed for 1" drop?

Ok so yeah just did the plumb bob method, looks like my rear end is being pushed to the passenger side by about half an inch or so.
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Old Sep 1, 2017 | 06:41 PM
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Re: Adjustable panhard bar needed for 1" drop?

Hanging a weight on one end of a string with the other end taped to the rear fender lip will only align the rear end visually. As was said it is not the correct way of doing it and at best will get you in the ballpark. At worst you will introduce drive line vibrations from the new horizontal angulation in the u joints. The center line of the body is not the center line of the drive line so knowing that why would you center the rear end to the body? The drive line is shifted towards the passenger side 0.400" Most guess that this was to make up for the room the steering system took up. Some people can just pop the hood and tell the engine isn't centered. If you're interested in having the underbody measurements and how to actually center the rear end where it should be then go to my build thread and read the latest page.
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Old Sep 1, 2017 | 06:56 PM
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From: Modesto, California
Car: 88 Firebird Formula
Engine: LO5 5.7 TBI/Ebl Flash
Transmission: 700R4
Axle/Gears: 2.73 stock rear end
Re: Adjustable panhard bar needed for 1" drop?

Originally Posted by Tibo
Hanging a weight on one end of a string with the other end taped to the rear fender lip will only align the rear end visually. As was said it is not the correct way of doing it and at best will get you in the ballpark. At worst you will introduce drive line vibrations from the new horizontal angulation in the u joints. The center line of the body is not the center line of the drive line so knowing that why would you center the rear end to the body? The drive line is shifted towards the passenger side 0.400" Most guess that this was to make up for the room the steering system took up. Some people can just pop the hood and tell the engine isn't centered. If you're interested in having the underbody measurements and how to actually center the rear end where it should be then go to my build thread and read the latest page.
Ok cool ty for info i will head to your thread now!
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Old Sep 6, 2017 | 09:42 PM
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From: Modesto, California
Car: 88 Firebird Formula
Engine: LO5 5.7 TBI/Ebl Flash
Transmission: 700R4
Axle/Gears: 2.73 stock rear end
Re: Adjustable panhard bar needed for 1" drop?

Finally getting some where... Hopefully




EDIT: on a side note, when replacing the rear lower control arms, does the rear suspension need to be loaded? (rear wheels on ramps?)

Im expecting a wrestle to get these in place like the front control arms because of the new bushings...

Last edited by Ghettobird52; Sep 6, 2017 at 10:08 PM. Reason: adding question
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Old Sep 7, 2017 | 06:34 AM
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Re: Adjustable panhard bar needed for 1" drop?

when replacing the rear lower control arms, does the rear suspension need to be loaded?
No; makes not the slightest difference. Whatever is easiest.

Im expecting a wrestle to get these in place
Probably not: they're usually pretty cooperative. Only thing is, do one side at a time, to keep the rear from deciding to turn/move/whatever. Probably easiest to put the chassis up on one set of jack stands at the "frame" end of the control arms, let the rear down all the way until it hangs then jack it back up about an inch or 2 to take the spring pressure off the shocks, then put a 2nd pr of stands under the axle tubes to hold it up off the shocks. NOT the pumpkin, NOT the control arm brackets, NOT the shock brackets, NOT anything else besides the axle tubes. In that state there will be almost no force trying to move the axle in any way, i.e. it should fight you the least.
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Old Sep 8, 2017 | 05:50 PM
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From: Modesto, California
Car: 88 Firebird Formula
Engine: LO5 5.7 TBI/Ebl Flash
Transmission: 700R4
Axle/Gears: 2.73 stock rear end
Re: Adjustable panhard bar needed for 1" drop?

Originally Posted by sofakingdom
No; makes not the slightest difference. Whatever is easiest.



Probably not: they're usually pretty cooperative. Only thing is, do one side at a time, to keep the rear from deciding to turn/move/whatever. Probably easiest to put the chassis up on one set of jack stands at the "frame" end of the control arms, let the rear down all the way until it hangs then jack it back up about an inch or 2 to take the spring pressure off the shocks, then put a 2nd pr of stands under the axle tubes to hold it up off the shocks. NOT the pumpkin, NOT the control arm brackets, NOT the shock brackets, NOT anything else besides the axle tubes. In that state there will be almost no force trying to move the axle in any way, i.e. it should fight you the least.

Awesome this is how i did it. The driver side i took a couple tries getting the bolts to line up, but the passenger side slid right in. Finishing up on the phb right now!

Thanks all for information and advice.
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Old Sep 8, 2017 | 06:37 PM
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Axle/Gears: Currie 9"/US Gear Lightning 3.00
Re: Adjustable panhard bar needed for 1" drop?

The suspension should settle down a little bit once the springs loosen up a little.

What angle did your LCA end up at?
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Old Sep 8, 2017 | 08:37 PM
  #19  
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From: Modesto, California
Car: 88 Firebird Formula
Engine: LO5 5.7 TBI/Ebl Flash
Transmission: 700R4
Axle/Gears: 2.73 stock rear end
Re: Adjustable panhard bar needed for 1" drop?

PHB is on! I set it to stock length for now (43" center of one bolt hole to the other) will adjust this weekend.



Originally Posted by Robbie_S
What angle did your LCA end up at?
Funny you ask that because at first when i got the lcas on and put the car on the ground it 'looked' as if they werent trailing down as much to the unibody. Then once i got the rear back in the air to do the phb i noticed they are pretty much at the same angle. These things are just beefy so they 'look like they helped.
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Old Sep 8, 2017 | 08:54 PM
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Car: 1989 Iroc Z
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Axle/Gears: Currie 9"/US Gear Lightning 3.00
Re: Adjustable panhard bar needed for 1" drop?

I guess you'll be able to figure out if the angle is all set once you start tearing around.
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Old Sep 8, 2017 | 10:01 PM
  #21  
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From: Modesto, California
Car: 88 Firebird Formula
Engine: LO5 5.7 TBI/Ebl Flash
Transmission: 700R4
Axle/Gears: 2.73 stock rear end
Re: Adjustable panhard bar needed for 1" drop?

pfft yeah once im able to rip down the street again! as soon as i start my car after replacing the lcas and phb its all crappy... I have a electrical problem now...

If you know electronics, see if any of you can help me out with a quick question; See my thread in electronics pls.

https://www.thirdgen.org/forums/elec...hook-wire.html
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Old Sep 8, 2017 | 10:25 PM
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Car: 1989 Iroc Z
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Transmission: 700r4
Axle/Gears: Currie 9"/US Gear Lightning 3.00
Re: Adjustable panhard bar needed for 1" drop?

I am the last one to comment on electrical. I am the Houdini of wires. I can make them all disappear in a puff of smoke.
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