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Discussion Starter #1
Will they noticeably help reduce the body roll?

I want to also look into them because Guldstrand says that the stock ball joints aren't strong enough.

Combined with the guldstrand bushings they should work nearly as good as what Norval did

Also they say that the smart struts help raise the roll center on the rear, but I don't see it helping any if you already have the correct "d" height

I'm just making sure becuase 140 is a lot to drop on ball joints :laughing:
 

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Will they noticeably help reduce the body roll?

I want to also look into them because Guldstrand says that the stock ball joints aren't strong enough.

Combined with the guldstrand bushings they should work nearly as good as what Norval did

Also they say that the smart struts help raise the roll center on the rear, but I don't see it helping any if you already have the correct "d" height

I'm just making sure becuase 140 is a lot to drop on ball joints :laughing:
stock no...MOOG yes....I run the standard MOOG Corvette ball joints and while they are expensive retail...you can get them on ebay if your patient...
(K 6034/K 6035)
.....redvetracr
 

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I had to switch to Howe ball joints when I put on the Savitske aluminum upper a arms. They are machined much better than Moog ball joints and have far smoother action. They are raised for better geometry. I'm not sure if you can use them on stock a arms, though.
 

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I had to switch to Howe ball joints when I put on the Savitske aluminum upper a arms. They are machined much better than Moog ball joints and have far smoother action. They are raised for better geometry. I'm not sure if you can use them on stock a arms, though.

is that a traditional ball joint or a monoball??
...redvetracr
 

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Discussion Starter #5
I believe they are mono balls

And they do make them for stock a-arms now

Although I do have vbandp ones
 

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Will they noticeably help reduce the body roll?
I didn't speak up when we were discussing this on CF but i don't get how roll centers can have any effect on how much a car rolls. I thought it was all just camber change.

So your car will roll just as much but the camber will adjust toward negative more aggresively is the way i understand it.
 

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Discussion Starter #7
I just used google

I wasn't really sure about it but I thought it helped reduced roll

http://www.eng-tips.com/viewthread.cfm?qid=184958&page=1

Edit: also wikipedia
vehicle is the notional point at which the cornering forces in the suspension are reacted to the vehicle body.

There are two definitions of roll center. The most commonly used is the geometric (or kinematic) roll center, whereas the Society of Automotive Engineers uses a force based definition.

The location of the geometric roll center is solely dictated by the suspension geometry. The SAE definition of the force based roll center is "The point in the transverse vertical plane through any pair of wheel centers at which lateral forces may be applied to the sprung mass without producing suspension roll". Note that it is a height only, the lateral location is irrelevant.

The significance of the roll center can only be appreciated when the vehicles center of mass is also considered. If there is a difference between the position of the center of mass and the roll center a “moment arm” is created. When the vehicle experiences angular acceleration due to cornering the size of the moment arm, combined with the stiffness of the springs and roll bars (sway bars in some parts of the world) dictate how much the vehicle will roll while cornering. This has other effects too such as dynamic load transfer.

Load transfer is of critical importance for vehicle stability in vehicle such as SUVs. Ideally in high performance applications load transfer tends to be minimised as a tyre's performance is directly affected by the amount of load that it has to transmit. In a steady state turn the final load transfer, summed across all the axles, is only related to the position of the center of mass above the ground, the track width and the lateral acceleration. SUVs must shift their center of mass lower or decrease their lateral acceleration to avoid tipping. To keep them from tipping many auto manufacturer use tyres with lower grip to reduce the vehicles cornering capacity, or the roll stiffness balance front to rear can be altered to encourage understeer or oversteer as necessary to limit the maximum lateral acceleration of the vehicle.

The geometric roll center of the vehicle can be found by following basic geometrical procedures when the vehicle is static. However, when the vehicle rolls the roll centers migrate. It is this movement of roll centers that vehicle dynamicists seek to control and in most cases limit. The rapid movement of roll centers when the system experiences small displacements can lead to stability problems with the vehicle. The roll center height has been shown to affect behaviour at the inititation of turns such as 'nimbleness' and 'initial roll control'.

Current methods of analyzing individual wheel instant centers have yielded more intuitive results of the effects of non-rolling weight transfer effects. This type of analysis is better known as the lateral-anti method. This is where one takes the individual instant center locations of each corner of the car and then calculates the resultant vertical reaction vector due to lateral force. This value then is taken into account in the calculation of a jacking force and lateral weight transfer. This method works particularly well in circumstances where there are asymmetries in left to right suspension geometry.
 

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:huh: My head hurts!

Man Ive got to stop reading this stuff. Im gonna have a friggin race car before it is over with...

Ditto, but if my upper balls ever need changing, I will put in long stemed balls then.....

:devil: :spanked:
 

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Who is that yellow73_clown? must be one of those holier than the pope whiners over @ CF maybe even douche bag himself, if not it's certainly a member of their circle jerkers society!

Anyway, those longer ball joints will change your roll center, how they do depends on the position of the instantaneous center that your arms make now.
 

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If you raise the roll center it will make the car roll less, it's a simple pole vaulters analogy, the lower the roll center, the easier it is for weight to shift and induce roll. Lowering CG and raising the roll center is an effective way to reduce roll (other than resorting to springs, shocks and bars)
 

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Discussion Starter #13
I'm honored that they choose to copy my name


The front is pretty low at 26.5 at the fenders. The radiator and front nose are about 1" lower also. I did this on accident :laughing:, I didn't realize that I did it until I went to install the sway bar. It must have sagged a bit when I did they new front end support.
 

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What you need to do is check the angles on the upper and lower arms, from ball joint center to cross shaft. use a machinist rule to connect the 2 and then use an angle finder. For the upper arm you must do it in the front and back of the arm as it's angled (cross shaft) for caster. The lower arm is pretty much level when it comes to the cross shaft, just record the angle there. Then You can to calculate the angle of the upper arm @ the ball joint intersection w/ the cross shaft (just measure how much offset the ball joint is from the center, I should have the measurements somewhere still, maybe theyér even still on corvettefaq) with these you'll have tha arm angles in the plane of the balljoint and this allows you to plot Ic in that plane and determine if it's outboard or inboard. Raising the ball joint will move it to inboard. If it already was inboard it will move it closer to the center. If it was outboard it'll bring it inboard, in either case it'll raise the roll center since the lower arm remains untouched and the IC closer to the car centerline will (even @ same IC height) raise the roll center
 

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Discussion Starter #16
I could just measure from the ground them from the ground and the distance in between them and use some trig to figure it out. I'll try a few things. It's pretty tight down there.

I remember seeing your measurements

Could you get an idea of if it's inboard or outboard from some pics?
 

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Yeah, a pic straight forward...you'll have to take the front clip off LOL

A quick indication may be all that's needed, use a tape measure and measure straight down from the upper arm to the lower. First use a set of strings or some tape to connect the cross shaft bolt to the pivot center of the ball joint. Measure this at a couple of places, if the 2 arms spread apart when going outboard that means they share an IC that's inboard, however most likely the arms will get closer as you go towards the balljoint.


Do you have an angle finder? It's much easier to use, you can just guesstimate the angle by holding the angle finder/protractor so it appears level w/ the line through cross shaft & ball joint.



This is what you're trying to find, this is for the front, same for the rear. Since the balljoint is off center to the rear of the a arm 'the true angle will be closer to the rear measurement. But, you can see from this pic, if you draw the line through the rear of the cross shaft it's almost level w/ the lower arms so in this case the IC is outboard most likely (it was, i measured it)

Here's the offset measurement for the upper arm (it's in mm!!!)
 
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