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Corner Balancing question...

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Old 04-11-2008, 06:39 PM
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BobbyC
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Default Corner Balancing question...

After corner balancing is the passenger side of the car higher than the driver's side? In my car the rear wheel fender on the passenger side is at least 1" higher than the one on the driver's side...
Old 04-11-2008, 06:48 PM
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Russ Murphy
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And your question is.......?
Old 04-11-2008, 07:09 PM
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mark kibort
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If you are running nascar, that might be true

seriously, you have to measure the chassis for ride hight at the measuring pads. and , when cornerbalanced, you want to set it up for the most common fuel load and passenger load. if not, its all a waste of time. (as long as its close) cross weights are probably more important.

mk


Originally Posted by BobbyC
After corner balancing is the passenger side of the car higher than the driver's side? In my car the rear wheel fender on the passenger side is at least 1" higher than the one on the driver's side...
Old 04-11-2008, 07:19 PM
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BobbyC
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Originally Posted by Russ Murphy
And your question is.......?
...is it supposed to be that way after corner balancing, i.e. the passenger side ride height is higher?
Old 04-11-2008, 07:59 PM
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Bull
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If there is any difference, the car would be slightly higher on the driver side if you are not in the seat (at the measuring pads). But it wouldn't likely be very much noticeably higher on the driver side even if it were set-up for me. Even measured at the fender well lips, one inch diff sounds like a lot.....and strange for it to be on the passenger side.
Old 04-11-2008, 08:00 PM
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Geoffrey
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It is not unusual for the driver's side of the car to be lower than the passenger side. This is because you need to take weight off of the driver's side (usually) and move it to the passenger side. You do this by lowering the corner(s) that are heavy thereby moving the weight to the other corners. You can of course raise the light corners too. There are many different ways to accomplish corner balancing by moving weight around the car and you need to take into consideration the final outcome in terms of ride height, rake, and corner balance. To answer your question, 25mm seems like a lot to me, but I've not corner weighted a car that heavy in awhile.
Old 04-11-2008, 08:03 PM
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Originally Posted by Geoffrey
........... To answer your question, 25mm seems like a lot to me, but I've not corner weighted a car that heavy in awhile.
25mm is a lot for cars of that weight.
Old 04-11-2008, 08:21 PM
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JoeMag
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would you mind posting the corner weights?
Old 04-12-2008, 12:35 AM
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Bryan Watts
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Having a car "corner weighted" is good, but changing ride heights should only be for fine balancing. If you've got to make significant changes in ride height between the sides of the car, you're better off just having a car that's "unbalanced". Moving weight around in the car is the way to accomplish large changes, and then use a turn or two on the adjusters to dial it in.
Old 04-12-2008, 10:01 AM
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SundayDriver
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It is always a trade off. You want perfect balance AND perfect ride height. You won't get both unless you have both shock and pushrod adjustment in the suspension PLUS the ability to adjust the floor height at the corners. (Been there, done that.) The height is critical in an aero car for downforce. In a production car it is not as important but if you get much variance, the suspension geometry differs from side tot side (e.g. - Camber gain) and that is not good.

Start by making sure the car was balanced with shocks on full soft and sway bars unhooked AND that the care was bounced between each adjustment. Also, was it done on a level setup platform? As others have said, it is measured at chassis points, not body work.
Old 04-12-2008, 04:28 PM
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spare tire
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Everyone who posted told you that a 1" differance from side to side sounds unusual. Get the weight at each corner and repost. There are enough people with similar cars here that we can help if we have all the facts. How does the car corner?
Old 04-12-2008, 07:50 PM
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analogmike
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Corner balancing should be done in 2 steps

1) set the ride height you want all around

2) set the corner weights WITHOUT changing the ride heights by adjusting
opposite corners the same amount but + on one diagonal and - on the other.

There are some errors in posts above.

Corner weights have NOTHING TO DO with ride heights, you can have the left high or low and still have the diagonals wrong either way.

Ride height changes do NOT shift weight around, only moving objects in the car can change your side to side or front to rear balance.

I wrote an article several years ago about alignment and it has the corner balance formulas towards the end. The only way to corner balance a car is by weighing the corners and adjusting until the numbers are correct and the ride heights are still correct.

http://www.pelicanparts.com/techarti...nment_tips.htm
Old 04-13-2008, 12:17 AM
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BobbyC
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This is a great community and forum! A wealth of knowledge, and people wanting to help. Love it...

Thanks to all for the valuable info and insights. We'll fix whatever needs fixing and I'll repost findings.

Cheers!
Old 04-13-2008, 02:50 AM
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wanna911
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I'm still confused.

But one thing is for sure, I still haveny gotten a quality CB if unconnecting the sways and running full soft on the springs is needed.
Old 04-13-2008, 10:11 AM
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SundayDriver
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Originally Posted by analogmike
Corner balancing should be done in 2 steps

1) set the ride height you want all around

2) set the corner weights WITHOUT changing the ride heights by adjusting
opposite corners the same amount but + on one diagonal and - on the other.

There are some errors in posts above.

Corner weights have NOTHING TO DO with ride heights, you can have the left high or low and still have the diagonals wrong either way.

Ride height changes do NOT shift weight around, only moving objects in the car can change your side to side or front to rear balance.

I wrote an article several years ago about alignment and it has the corner balance formulas towards the end. The only way to corner balance a car is by weighing the corners and adjusting until the numbers are correct and the ride heights are still correct.

http://www.pelicanparts.com/techarti...nment_tips.htm
I strongly disagree. If you only have one height adjustment (such as spring perch) as you move that up or down you will change BOTH the corner weight AND ride height at the corners. Now if you only measure ride height at a single, center location front and rear, then you can probably maintain it as you adjust, but that is not the correct way to measure ride height. On my car, I measure it in 8 locations but I have a lot more adjustments than a street based car.

The concept of raising one corner and lowering the other to hold height does not work, unless the chassis is so floppy compared to the springs, that it is the chassis flexing, not the suspension. Hitting the opposite corners equally will tend to; 1) Maintain diagonal corner weight, 2) Tilt the car around the opposite axis which changes height & 3) change balance from side to side while holding diagonal balance.

There is a very direct relationship between adjusting the suspension to corner balance and ride height of any corner you adjust. What it does not do is change the CG of the car - in other words, you are correct that corner balancing does not move weight inside the car, but it does change which corner carries how much.


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