grant
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Upper control arm angle mods

Post by grant »

Hello,

I went to my first track day with my current setup consisting of RSR front coilovers with dropped spindles, and Camaro rear springs and Bilstein shocks.

The improvement over my old Shankle stuff was pretty dramatic, even on street tires.

Anyhow, I would like to know if it would be a bad idea to mount the upper ball joint below the UCA to increase the camber gain?

Any other methods for further increasing camber gain besides just dropped spindles?
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Post by Mats »

The only way that would work is if you get the pivot points of the upright further apart and moving the control arm won't do that.

I also think that you do not need any more camber gain, there will be issues during braking and just from wheel travel.
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Post by grant »

OK, so it's the deal where just the UCA changing angles is not the same as actually changing the pivot points then?

I think I remember thinking about that a while ago. My memory sucks at the age of 21...and it's not because of beer..I'm worried.

I have not taken tire temps yet, but I hope to be able to next time. What I have noticed though, is in the pictures, I am still rolling over a lot under hard cornering. I think I could gain some grip if the camber gain was further optimized. I have about 2.1 degrees of static camber, caster is 4 and 0 toe.

I have stiffer spring rates now, I'm not as concerned with the loss of braking performance under dive as I used to be. Should I?

The milano is showing much more promise than it used to, this was the first time I enjoyed the handling of my car at the track!

I appreciate your input Mats, please continue.
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Post by Mats »

For starters I'd add a (1) degree or so of static negative camber, depending on what tire you use of course but I'm guessing it's some kind of semi-slick?

Making the car more roll-stiff will also be beneficial for static versus corner camber.
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Post by grant »

This car is my daily driver. I think 2.1 degrees is as far as I dare go. No semi-slick, just yoko ES100 for now. I want to get the suspension sorted before I buy expensive tires.

Can you see why I want to increase camber gain? I can't run as much static camber as I want to.

But, can you confirm that it's the ball joint position moving, and not the visual angle of the UCA?
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Post by Micke »

The geometry is determined by the joints (middle of the ball). Whether the control arms look like bananas or are straight does not matter.
If you want to add camber gain with the UCA you need the so called knuckle raisers. It's a piece to lengthen the spindle upwards. I'm sure here are photos on the forum if you search.
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Post by grant »

Thanks Micke. I'll look into it. I wasn't aware knuckle risers were made for this chassis as well.
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Post by grant »

OK, I looked a while but didn't fine the pics. Most of the concern seems to be with the LCA angle.

Do 116 knuckle risers resemble 105 ones? I'm guessing 105 knuckle risers won't work because of different ball joints.

I looked at a picture of a stock 350Z fully loaded in a cambered turn, the camber gain was remarkable, must have been around 3.5-4 degrees of camber when loaded, and the tire tread looked pretty optimal with the pavement. I think I'm losing out on some grip here.
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Post by Daniel »

Grant
Talk to Barry, he's made 105 ones but I thought they fitted 116s as well.
http://alfagtv6.com/bb/viewtopic.php?t= ... 5c37405526
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Post by grant »

Barry, please post here when you see this!

Another issue:
Should I be worried about the roll center shifting from left to right if I tamper with the UCA angle? What issues would crop up with a roll center that shifts under cornering?
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Post by Carel »

Hi All/Grant

Knuckle risers or any lengthening of the spindle/upright will give you the camber gain you want, but when you look at the suspension holistically, I would rather lengthen the bottom. This will ensure that you can lower the suspension and maintain a horizontal LCA; this will ensure that the roll centre stays higher, more in line with the rear.

There are a couple of ways of doing it, make a longer spindle/upright or for me the easiest is to put in an upside down ball joint in at the bottom. Search the threads here and you will find oodles of info on how to do it, and even pics of other installations.

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Post by rz »

hi grant, try using caster 1 degree, 1 degree camber and toe in 1 degree 8)
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Post by grant »

Carel, I already have dropped spindles. 1 and 1/16th inch...I already had to do some grinding just to mount my 15's!

RZ, I don't know if you're being serious or not :oops:

Anyhow, if I could set camber at 3 or more degrees, I wouldn't need knuckle risers in the first place.
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Post by Mats »

rz wrote:hi grant, try using caster 1 degree, 1 degree camber and toe in 1 degree 8)
I hope you mean 1mm of toe in?
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Post by Maurizio »

Maxing out castor will also increase dynamic camber.
On my ts I run 6 deg castor, this is the maximum I could set without hitting to upper arms with the dampers.
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