How is caster adjusted

[ConeCrazy02]

I went to firestone for an alignment and the tech didnt know or cant adjust the caster. So my question is how do you adjust the caster?

[oldschoolimport]

caster is the angle that the strut sits at. the top mount can be slid back or forward on some cars. or the bottom arm can be manipulated to move the lower ball joint forward or back. caster is what makes the steering wheel straighten when you let go or go to full lock on twitchy cars, depending on how it is set. hope this helps.

[Suk02Si]

I thought caster was the angle of the front hub/knuckle

http://www.mgf.ultimatemg.com/caster.htm

http://www.mgf.ultimatemg.com/Caster.gif

[oldschoolimport]

caster IS the angle of the hub/ knuckle/strut to vertical, looking at it from the side of the car. like casters on your desk chair, it is not straight over the axle point.

caster is front to back angle of the strut
camber is in and out angle at the top of the tire
toe is in and out of the forward tread section of the tire

was that not what I said????
caster is the angle that the strut sits at looking at it from the side. I guess I need to be more clear:D

[Suk02Si]

oops, I guess I misunderstood you :D

I thought when you said 'strut' you were referring to the angle of the Shock itself :)

[cpu519]

On my Mustang 5.0, which has basically the same front suspension, before they came out with camber/caster plates (pillow ball mounts), caster was adjusted by moving the subframe fore and aft to get the angle you wanted. Adjustment is limited to the "slop" available at the mounting bolt holes, some people enlarged the holes to get more adjustability. Moving the subframe forward increases caster, back decreases.

I'm taking out the subframe on my Si to do some work, afterwards I'm taking my car to an alignment shop experienced in this kind of work so they can get everything squared up again. I'll have them adjust the caster angle if they can by moving the subframe as far as the bolt holes allow.

Is there a higher performance caster setting than stock? If so I'll have them set my car to that, or as close as possible.

[ConeCrazy02]

so to adjust the caster I would have to have a camber plate?

[cpu519]

That would be the easiest way to adjust caster. Only thing is the available camber plates (pillow ball mounts) like the Ground Control (only works with their coil over kit I think) and the one that comes with Tein Flex only adjust camber. There is another one that I'm checking into from Australia from a company called K-Mac that does allow adjusting camber and caster. It should work with the stock struts and springs. Here's the link, it's Part No. 331216. It's the model for 2000-2003 Civic and 2001-2003 Integra.

http://www.k-mac.com.au/

[Suk02Si]

Originally posted by ConeCrazy02
so to adjust the caster I would have to have a camber plate?

I don't think you can adjust the caster on our car unless you angle the subframe differently.

With R/C Cars we used to place washers under the the pivot block so the arms/hubs/spindles would angle slightly. Depending on the size of the washer, usually one washer=25 Deg.

Maybe this can be done to our cars? Some how angle the subframe, via washers or something, so they would kick back slightly.

:)

[cpu519]

Originally posted by Suk02Si


No, I don't think you can adjust the caster on our car unless you angle the subframe differently.

With R/C Cars we used to place washers under the the pivot block so the arms/hubs/spindles would angle slightly. Depending on the size of the washer, usually one washer=25 Deg.

Maybe this can be done to our cars? Some how angle the subframe, via washers or something, so they would kick back slightly.

:)

I know exactly what your saying Suk02Si, the washers change the angle that the suspension is inclined from the top. On your picture, if you move the subframe forward you are changing the angle that the top mount (top of strut-unmovable) and the ball joint (moves with subframe) produces from vertical. An adjustable camber/caster plate will do the same thing, except you move it rearward to increase the caster angle, whereas moving the subframe you would move it forward.

Check the October issue of Sport Compact Car with the Realtime Racing RSX test drive. If you look at the picture of the engine compartment you'll see that they moved the top strut mount rearward. That car has two strut mount locations, the picture shows it using the rearward set up. They are increasing the caster angle, probably for more high speed stability.