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Leveling car: sway bars hooked up?

Feel like I am scattergunning you guys with all these questions -- least I could do is get them all in one post...

When I leveled my car, I did so with the sway bars attached. Leveled the front with the adjustment screws, then to the back and driverside, then passengerside.

Should I have, as a minimum, have unhooked the rear sway bar (I can't imagine trying to get the fronts back out of the new bushings...)? Can I get away with just one side, unbolting the bolt into the swingarm, or do I undo them both?

Reason I ask is after grazing Ray Scruggs home alignment book I noted this and remembered reading so on this 'board.

One more question: Ray says that, once the heights are close to where you want them, adjust side to side hi/lo using only the front adjusters, since one corner will affect the other corner/side. Any opinons on this?

Many thanks,
John
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Old 02-10-2004, 06:36 AM
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Always disconnect the sway bars when corner balancing/setting ride height.

One side only is all that is necessary. The bar will preload the suspension if you don't.
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Old 02-10-2004, 06:39 AM
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OK educate me.
I know the accepted method is to disconnect the sway bars when corner balancing. To me that only makes sense when you have sway bars with adjustable links that let you dial out the preload. On a car with non-adjustable sway bars I just leave them connected. I want the corner weights as the car will actually be used. You wouldn't ask the driver to get out of the car when you corner weight it "because he'll effect the weights" would you?
just my opinion,
Chris
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Old 02-10-2004, 06:49 AM
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Both front and rear then? Boy, I sure don't want to deal with that front sway bar again...

Guess I'm going back in boys...

John, adjusting to adjusting.
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Old 02-10-2004, 06:53 AM
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Quote:
Originally posted by ChrisBennet
when you have sway bars with adjustable links that let you dial out the preload. On a car with non-adjustable sway bars I just leave them connected. I want the corner weights as the car will actually be used. Chris

Chris, you are spot on.

With non-adjustable drop links, set ride height and corner balance with the sways attached. With adjustable drop links, disconnect. After you have the height/corner balance complete, adjust the drop links so there is no preload.

With non-adjustables, you can't dial out pre-load. So your best alternative is to set height with the bars reflecting real conditions.
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Old 02-10-2004, 07:00 AM
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Here's a question.

What effect would occur if only the front bar was preloaded?

Meaning, if I were to remove the solid droplink and install threaded rod ends at the rear swaybar of my car. But i'd leave the front bar as is until I got around to installing an adjustable front bar. What type of handling effect might we see here?
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Old 02-10-2004, 07:09 AM
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My to do list to insure repeatable corner weights (so that I am not chasing after an elusive perfect cross-weight balance) is as follows:

Each scale pad exactly level with itself (North, South, East, West) and with the other three pads. I use slide plates on top of scales, so I am actually measuring the slide plates for level.
Disconnect front and rear anti-rolls bars
Dial down bump and rebound settings to full soft
Set tire pressure to my ideal "hot" pressure for each corner for the next track (very important - I was surprised at what a difference a few pounds of pressure can make to a corner weight)
1/2 tank of fuel, driver in and his seat at his driving position and all race gear in position (i.e., in car camera, etc.)

I also set up a little Exel spreadsheet to that when I punch in the four weights, all the cross weights, percentages, etc. that I want are automatically updated.

True, it is a lot more up front set up time, but I find that I can then dial in to within 10# of desired in about 3 perch moves and then also being able to yeild the same results when I double check.
Old 02-10-2004, 05:46 PM
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Before I go ahead and head out to Truline for the alignment, do I understand we are in agreement that the non-adjustable sway bars ought NOT to be disconnected for initial height set?

Different for adjustables as discussed?

many thanks,
John
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Last edited by Jdub; 02-11-2004 at 12:03 PM..
Old 02-11-2004, 09:17 AM
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Quote:
Originally posted by Steve Beddor
I also set up a little Exel spreadsheet to that when I punch in the four weights, all the cross weights, percentages, etc. that I want are automatically updated.
Check out http://vintagebus.com/cgi-bin/balance.cgi
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Old 02-11-2004, 09:33 AM
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Steve is right-on with his instructions. I use my 6-gal water jugs for driver ballast because no one can sit still enough for accurate and repeatable measurements. I tend to bounce on the car and repeat the measurements many times.

The critical issue here is your suspension must be free. Try lifting one corner and measure. Then try and compress that corner and measure.

You only need one sway bar link to be adjustable length. Spherical bearings are nice but not absolutely necessary with stock suspension.

When you are all done adjusting spring plates and torsion bar screws, then adjust the length of the sway bar links so the bolt just “slips” in.

Best,
Grady
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Old 02-11-2004, 09:46 AM
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Quote:
Originally posted by Grady Clay
Steve is right-on with his instructions. I use my 6-gal water jugs for driver ballast because no one can sit still enough for accurate and repeatable measurements. I tend to bounce on the car and repeat the measurements many times.....
....When you are all done adjusting spring plates and torsion bar screws, then adjust the length of the sway bar links so the bolt just “slips” in.

Best,
Grady
Totally agree. However the question is regarding a T-bar car with stock NON-adjustable ARB's. In this case, it doesn't make sense to disconnect them, (as Chris and Chuck already mentioned), especially on a street driven car. I'm thinking Steve was referring to one of his (Ruf?) track monsters with coilovers, 3-way dampers, and adjustable ARB's. That makes things a little easier.
Old 02-11-2004, 11:17 AM
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Eric,

I still think the initial balancing should be done with a front and rear ARB link disconnected. He can then re-attach the links and repeat the measurements. If they change dramatically then there is a real need for adjustable links.

I also agree that if nothing else is going to be done then balance the car with everything in place as driven.

Something else. After the corners are balanced, measure the ride height of each corner. It is possible to balance a crooked car. Remember to check/set your toe and camber last. Everything again after driving.

Best,
Grady
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Old 02-11-2004, 11:58 AM
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Quote:
Originally posted by Grady Clay
Eric,

I still think the initial balancing should be done with a front and rear ARB link disconnected. He can then re-attach the links and repeat the measurements. If they change dramatically then there is a real need for adjustable links....

Best,
Grady
Ah, that's where there may be some confusion. I believe on Jdub's car the front bar has no links. It is a one-piece bar that fits into bushings on each A-arm. They are a REAL pain to remove/install.
Old 02-11-2004, 12:47 PM
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If the car is level, LF/RF and LR/RR, then you could probably corner balance and remain balanced with non-adjustable sway bar drop links.

If the car is not absolutely level, side-to-side, then the fixed sway bar links will impart a preload on the suspension. You decide whether you wish to spend a few hundred $$ on corner balancing and then compromise the settings by preloading the chassis. Doesn't make much sense to me. You could just purchase an adjustable drop link <$100/set for one side, balance, then enjoy a balanced chassis.

However, I suppose closer to "balanced" is better than being way off.

Sherwood
Old 02-11-2004, 12:57 PM
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Great stuff guys -- I encourage anyone reading this thread and considering rebuilding F/R suspension to consider the adjustables.

I did not, and am wondering if I ought to have.

Yes, I REALLY do not want to have to unbolt the front sway bar and have at it. I guess my plan now is this:

1) Gas tank to 3/4, tire psi to 32/36 (7"/205; 9"/245)
2) Set front toe to 1/8 neg to permit driving
3) Set height, drive, reset height, drive again, check
4) Off to Truline

The car is pure street. For that reason I am going like this:
Front:
Camber: 1/4-1/2 degree
Castor: Midrange
Toe-in: 1/8"

Rear:
Camber: 1/2 degree max.
Toe-in: 0 degree

Comments welcome,
John
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Old 02-11-2004, 01:16 PM
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Quote:
Originally posted by Jdub
...The car is pure street. For that reason I am going like this:
Front:
Camber: 1/4-1/2 degree
Castor: Midrange
Toe-in: 1/8"

Rear:
Camber: 1/2 degree max.
Toe-in: 0 degree

Comments welcome,
John
John, those seem like very conservative settings. I'm sure you will enjoy a few "spirited" drives here and there. For that reason, I would recommend "lightly agressive" settings.
Something like this:

Front:
camber: -1 degrees
castor: 6+ degrees
toe-in: .01 to .04 degrees

Rear:
camber: -1.5 to -1.8 degrees
toe-in: .07 to .09 degrees

You won't get any adverse/preamature tire wear, and the car will feel solid and very stable.

Old 02-11-2004, 02:21 PM
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Eric, You are right on for conservative good handling street settings.

Also you are correct, I forgot how his sway bars were mounted. The way to disconnect for balancing is to undo the mounts to the chassis and let the entire sway bar hang free. Is that correct?

Best,
Grady
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Old 02-11-2004, 04:23 PM
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Oh yes, I forgot.
You can shim the mountings to the chassis so as to not pre-load the sway bars.

Best,
Grady
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Old 02-11-2004, 04:36 PM
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Grady,

Spot on. Good info.

Old 02-11-2004, 04:47 PM
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