hi guys

im trying to get my head around how castor affects stability/handling

i hear so many people mention how such a small mod gives great gains
but dont quite understand it totally..

ive got basically no room (without modyfing my front guards) to pull my
front wheels forward, does mounting the top of the strut further back in the tower
acheive the same result?

Quote:

Yes!

as to how to explain it??

I kinda get it but not good enought to pas it on.

Agreed, I recently had my sedan re-aligned and managed to get +4.25 degrees castor without modifying the guards. Pull the lower end forward with teh use of the adjustable castor rods and the tops rearward with the S13 camber plates installed diagonally. . Ended up with neg 0.5 degrees camber at resting height. I also have the B-pro 30mm bump steer spacers to retain some angle in the LCA with my very short B110 struts.

Dont go too radical with pulling the LCA forward as this will put strain on the LCA pivot bushes [trying to rip them out of the engine crossmember.

Positive castor helps the eliminate the straight line wander at speed. 1200's can be a bit floaty at speed. Cornering is a different story.

ROConnor: haha i know what you mean, i kinda get it
but a 1200 specific explanation would be tops

Benny: only 0.5 deg neg? was the max neg camber or a setting you chose?

what would the castor be on an unmodified 1200 front end?

i kind of get it but im using more castor on threaded castor rods (not using the full threaded part currently).

also fine tuned with s13 cambet ops asdid piggy and boof by installing on a diagonal angle. reduces neg camber slightly on mine but castor did make car feel more stable bt with slightly increased steering effort (no drama in a 1200 and i thought gave more feel through the wheel too for input into a corner)

Dont worry about the gas stuff, just look at the angle of the camber top gives castor and camber adjustment this way

1200 specific setup steps or castor explained better?

a better explanation of castor would be great

thanks for the pic mik, ill do the same to mine
but whats all the stuff on your firewall?

Benny, Have seen moded control arms with rod ends to eliminate the bushing problem. I went and bought some bits to do this, but as you know have given up on the 1200 for now.

from wiki

The pivot points of the steering are angled such that a line drawn through them intersects the road surface slightly ahead of the contact point of the wheel. The purpose of this is to provide a degree of self-centering for the steering - the wheel casters around so as to trail behind the axis of steering. This makes a car easier to drive and improves its directional stability (reducing its tendency to wander). Excessive caster angle will make the steering heavier and less responsive, although, in racing, large caster angles are used to improve camber gain in cornering. Caster angles over 10 degrees with radial tires are common. Power steering is usually necessary to overcome the jacking effect from the high caster angle.

http://en.wikipedia.org/wiki/Caster_angle

The steering will be heavier on cornering due to the stub axle changing angle [arc] as the struts are turned left or right. for example sake the stub axle [tip & base] would be parallel with the road surface when travelling straight but as you turn the tip will move between say 0 degrees and +5 degrees as it moves in the arc left or right away from the road surface. Hope that makes sense.