Setting camber/caster angles on xmods

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color0
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Setting camber/caster angles on xmods

Post by color0 »

this is comprehensive for both gen 1 and evo, and i have diagrams for both. however, it is more than likely a one-time mod, meaning the settings are permanent. before and after pictures will be added soon.

tools/materials required:

exacto knife
superglue
toothpick


for evo:

the front and rear rely on the same suspension concept, so the following instructions work for both ends of the car.

1. here's the top view of our evo around the front left knuckle area.

Image

2. to increase negative camber, we move the hole some distance towards the centerline of the car. to increase caster, move the hole back. each 0.25mm corresponds almost exactly to 1 degree of negative camber or caster (depending on which direction you move the hole). this diagram, and the following depict a camber change only.

Image

3. take an exacto knife, and scrape away at the inside edge of the hole until you reach 0.25 or 0.5mm or however much you want the knuckle to move in (remember, 0.25mm = -1 degree camber/caster). now the hole should be elongated into an oval.

Image

4. the red circle denotes our final hole; to achieve it, we have to fill in part of the original hole with superglue. the space between the black semicircle and the red circle is where the superglue should be applied. use a toothpick and small dabs, allowing the surface tension of the superglue to do its work.

Image

5. when the superglue dries, it should leave a circular opening that is some distance offset from where our original hole was. the superglue should not need sanding in most cases, as most formulas dry smooth. if you applied too much, a strip of sandpaper looped through the hole can help you sand away the excess. sand until your knuckle fits snugly (but easily) through. the red hole is the final result of our modding.

Image

as stated before, the process is identical for the rear, except that the rear suspension can only take increased camber (caster, or anti-squat, in the rear will bind up the suspension).



for gen 1:

for the front, the process is the same, except that the hole should be moved outwards and forwards to increase camber and caster respectively. thus:

Image

note that offsetting the hole more than 0.5mm (~2 degrees) will weaken the chassis.

when finished, the final hole is offset outwards instead of inwards.

Image

for the rear, the suspension arms should be shimmed so that the suspension arm sits at the correct angle when the car is at rest. arrow points to the required shim. when making this shim you should start off thick, glue it to the chassis, and sand off until you reach the desired amount of camber. note that this will affect your ride height slightly depending on how much negative camber you end up with.

Image



pictures:

note the slight positive camber in the evo (highly undesirable; i believe it's the wheel's fault) vs. the negative camber in the gen 1:

Image

the gen 1 rear camber fix; the shim is very thin, on the order of 0.25-0.5mm:

Image
Greyscale Racing
Maxximum Attack
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Post by Maxximum Attack »

Great tut Color0. But tell me, performance wise, how does the -ve camber actually help the Gen1? I'm looking for another non electrical steering fix, as I need a little less turning radius for my speed bump-up. Maybe a more exaggerated camber angle? that may weaken the chassis tho :???:

I think on the EVO that this should be purely cosmetic as it already has good handling.

Thank you none the less. A very well written, comprehensive tut.

Maxx
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betty.k
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Post by betty.k »

thanks for going to all that trouble bloke :-)

max, camber is far more than a cosmetic adjustment, a good contact patch makes a huge difference in handling :-o
i used to be cool
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color0
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Post by color0 »

after adjusting the camber, i got my gen 1 to rotate more off throttle; it has more grip now, i find that the drifts i pull always take more throttle now to get the same angle.

also, the inside front tire is hooking into the gaps in my marble floor... well, small prices to pay for more grip. i can pull "gutter runs" now, lol...

a friend suggested that jbweld on the outside of the gen 1 knuckle hole may be able to reinforce the hole enough for more than -2 degrees of camber.
Greyscale Racing
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Post by Maxximum Attack »

On closer inspection of my Gen1, it seems that my "man-handling" of her actually elongated her holes :lol: . No pun intended Image. So now I just have to fill them with super glue to make this camber permanent. I knew what camber adjustment was for, but I wanted to know if it was functional at this scale or just for looks, thanx tho betty.

Maybe my camber will be a full -4 degrees, I think the holes may be a full 1mm off. So steering has improved? we'll see on sunday when I run her. It's nothing like tight turns tho right :( I hope not. I'm so accustomed to the wide turns of my wrx that I can't get a TT Xmod driven.
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