[Land-speed] Sunbeam Alignment Stuff

[drmayf]

Ok, so today I put the car down on its feet and decided to do some 
tinkering regarding alignment parameters. I first built a couple of 
tools to make it easier for me to measure camber and toe angles.   When 
I measured the camber I found that the drivers side was at 1 degree 
negative (leans in toward the motor) while the passenger side is neutral 
at 0 degrees.  I can adjust the the camber reasonably easy to make it 
pretty much what is required. But there is the rub. This is a completely 
custom chassis.  So given that the wheel base on this puppy is really 
short at 90 inches, what the consensus for a good toe measurement? I am 
running a 24 inch diameter front runner. Is there a relationship between 
wheelbase, track width, tire diameter and toe measurements? Is the old 
standard of  about  1/8 toe appropriate for a short narrow car?  The 
Sunbeam Tiger toe is supposed to be 1/8 inch.  Does speed affect the toe 
requirements?

Also, what should camber be? I tend to like some negative camber 
(leaning in towards the motor)  although not much. I wouldn't mind 3 
degrees negative camber but, again, what is a fair number?

Here lately some of us  locals have been chatting about scrub radius. 
Scrub radius is the distance from the Suspension angle (ie the angle 
made by a line drawwn through the upper and lower ball joints when 
viewed from the front) where an imaginary line intersects the road 
surface and the centerline of the tire tread.  While I have not 
generally measured many of these, I suspect that most cars have 
somewhere in the 2 to 3 inch range of radius. That would mean the the 
forces developed by the tire at the center of the tread would act on a 3 
inch radius making  torque trying to move the tire into a turning 
movement, left on the drivers side, right on the passenger side.  When 
going dead straight those two forces cancel out. When making a turn, say 
left then things can go strange. In cars like mine with lots of caster a 
turn left is trying to lift the drivers sideof the car adding more load 
to that tire while on the other side it is trying to raise the tire 
lessining the load. Since the left wheel has more load then the force 
balance is upset and that would seem to make it seem like it has power 
steering. Easier to turn.  Maybe too much so, lol.  But with very small 
corrective turns on the course to keep it between the lines, I suspect 
that the effect is neglible. And yet, the faster you go the more it 
probably seems it is moving. A small twitch must seem like a monstrous 
movement at 300 plus mph. 

Again, what is considered a good suspension angle as well as an 
acceptable scrub radius? Any rationale floating around out there?

Any discussion on any of these items?

mayf