FWIW I solved my rear unequal ride height
02-07-2016, 11:34 AM
#1
Melting Slicks
Thread Starter
FWIW I solved my rear unequal ride height
I have been fighting a rear unequal ride height for a very long time now. The unequal height left to right became worse after mounting a stiffer front stabiliser bar and it started to dawn on me.
Anyway, on our cars, when the front right goes down, the left rear goes up. On the other side, when the left front goes down the left rear goes up.
I always had the front right and right rear sit too high.
This is what I did :
I loosened the stabiliser end links left and right in the front. I then jacked up the left rear so it was equal in height to the right. This made the front sit equal too.
I then mounted my link on the lowest front side, meaning the left front and torqued down the bolt.
When fitting up my end link on the right it would go in. The bar end was too close to the control arm which was to be expected. I shortened the metal tube that goes in between the bushings ca. 15mm and bolted everything down et voila : when taking the jack out everything was almost equal left to right both in the front and in the rear.
Anyway, on our cars, when the front right goes down, the left rear goes up. On the other side, when the left front goes down the left rear goes up.
I always had the front right and right rear sit too high.
This is what I did :
I loosened the stabiliser end links left and right in the front. I then jacked up the left rear so it was equal in height to the right. This made the front sit equal too.
I then mounted my link on the lowest front side, meaning the left front and torqued down the bolt.
When fitting up my end link on the right it would go in. The bar end was too close to the control arm which was to be expected. I shortened the metal tube that goes in between the bushings ca. 15mm and bolted everything down et voila : when taking the jack out everything was almost equal left to right both in the front and in the rear.
Last edited by Belgian1979vette; 02-07-2016 at 11:34 AM.
02-07-2016, 12:54 PM
#2
Le Mans Master
Two quick questions...
1) Did you have your approx. weight in the driver's seat?
2) Have you any way to check your cross-weights for wedge?
1) Did you have your approx. weight in the driver's seat?
2) Have you any way to check your cross-weights for wedge?
02-07-2016, 02:09 PM
#3
Safety Car
Member Since: May 2004
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Supplementing what TheSkunkWorks said, look here.
http://robrobinette.com/corner_weight_calc.htm
However to do this right you will need to borrow a set of corner weight scales somewhere and plunk the car down on them. You are on the right track but unless your frame is bent somehow, you probably have an unequal length or weak spring somewhere.
http://robrobinette.com/corner_weight_calc.htm
However to do this right you will need to borrow a set of corner weight scales somewhere and plunk the car down on them. You are on the right track but unless your frame is bent somehow, you probably have an unequal length or weak spring somewhere.
02-07-2016, 02:45 PM
#4
Melting Slicks
Thread Starter
02-07-2016, 02:46 PM
#5
Melting Slicks
Thread Starter
Supplementing what TheSkunkWorks said, look here.
http://robrobinette.com/corner_weight_calc.htm
However to do this right you will need to borrow a set of corner weight scales somewhere and plunk the car down on them. You are on the right track but unless your frame is bent somehow, you probably have an unequal length or weak spring somewhere.
http://robrobinette.com/corner_weight_calc.htm
However to do this right you will need to borrow a set of corner weight scales somewhere and plunk the car down on them. You are on the right track but unless your frame is bent somehow, you probably have an unequal length or weak spring somewhere.
Basically without cornering a stabiliser bar shouldn't be 'loaded'
I don't think there is a weak spring either. Body off resto, so almost everything is new, especially the spring in the rear.
Last edited by Belgian1979vette; 02-07-2016 at 03:01 PM.
02-07-2016, 06:02 PM
#6
Team Owner
"Wedge" is the inequality in diagonal cross weights. By playing with this setting, oval trackers use the inequality in order to get the car to turn left. On a road racer, or street car, you want this to be as equal as possible.
02-07-2016, 06:33 PM
#7
Le Mans Master
In as much as it is practical to do, a performance vehicle's all-up weight should be factored into the equation when doing alignment, ride heights and/or corner weights. For setup work I suggest simulating driver's weight with tube sand or barbell weights and 1/2 a tank gas on board.
Yes, as leadfoot4 said, "wedge" refers to differing cross-weights (LF+RR vs. RF+LR). Ideally, a car intended to take both right and left turns should have no wedge, while jacking wedge into a circle track car is a common in-race tuning adjustment. FWIW, if your all-up LF+RR weight happens to be less than RF+LR, your car will tend to understeer more in left turns and less so in right turns.
Agree with ignatz regarding the likelihood of a bad spring and/or tweaked frame, so I'd definitely recommend digging into this further. In the mean time you might proceed with caution until determining whether and to what extent you may have altered your car's handling characteristics.
..
Yes, as leadfoot4 said, "wedge" refers to differing cross-weights (LF+RR vs. RF+LR). Ideally, a car intended to take both right and left turns should have no wedge, while jacking wedge into a circle track car is a common in-race tuning adjustment. FWIW, if your all-up LF+RR weight happens to be less than RF+LR, your car will tend to understeer more in left turns and less so in right turns.
Agree with ignatz regarding the likelihood of a bad spring and/or tweaked frame, so I'd definitely recommend digging into this further. In the mean time you might proceed with caution until determining whether and to what extent you may have altered your car's handling characteristics.
..
Last edited by TheSkunkWorks; 02-08-2016 at 11:42 PM. Reason: slight correction