Sorry i've been slow everyone Im always busy with school, heres a diagram to explain SAI and IA in relation to camber. sorry the background sucks in the first pic. the second is easier to see but the references to positive or negative SAI in the second diagram are NOT TALKING ABOUT ANGLE IN DEGREES. ignore those labels for now.

Ok, so over christmas break I basically did a mechanical restoration of my suspension and steering components, among a few other things

This included (not in order):
new tires
alignment
rodney dickman shift cables/shifter rebuild/select arm rebuild/short shifter
new upper and lower ball joints
new front poly control arm bushings (replaced worn poly ones)/ rodney dickman rear suspension link bushings
new spring pads all around
new shocks and struts (slightly stiffer than stock) (with new bump stops/boots/and strut plates)
front and rear poly sway bar bushings and rodney dickman solid end links
new steering rack passenger side bushing (rodney) plus inner/outer tie rods
new master and slave cylinder for the clutch
( have new engine/trans mounts,brake master cylinder, window guides/dew wipes that I need to put on, just havent had time...)

...whew I think that covers it. needless to say it drives like a completely different vehicle.

some pics




heres before and after alignment (they got rear toe wrong... ugh)
it should be noted that i requested an extra -.5 degree of camber all around, then maximize castor


so with my camber at -.5 my SAI should be (6-(-.5)) which is 6.5 degrees. now I should have everything I need to plug into that beast of an equation.

I should be able to make an excel spreadsheet, where fiero owners could enter their current alignment specs and know their camber at a given steering angle.
Additionally, I could solve for camber at a given steering angle(toe), and see the effects DIFFERING CASTER ANGLES have on camber AT THE SAME STEERING ANGLE. This was my original intention for figuring all of this out.

People love to talk about adding camber, but castor causes the camber of BOTH wheels to lean correctly in turns (not just the outside tire). (Ever seen the way wheels are leaning when parked at full lock?) plus the fact it aids in self centering, and wont wear out tires like camber..... food for thought

[This message has been edited by guitarfreak235 (edited 02-10-2017).]

quote Originally posted by pmbrunelle: The steering axis is defined by the two ball joints. More specifically, the center of the ball in each ball joint. I would suggest you find a junk upper and lower ball joint, and slice them in half (Dremel?) in order to extract the stud and ball part of each joint. Take a flat piece of plywood, drill some holes in it to accommodate the hub sitting flat on it, then place the knuckle and bearing assembly on the plywood. Install the ball joint stubs into the knuckle. Measure the distances between the balls and the plywood. Presumably, you'll also need to know the distance from the hub face to the steering axis, so you'll get that info as well from the above test. Obviously, share your findings if you take measurements. Otherwise, use the search function, the info may be available, but how confident will you be in its accuracy compared to measured values? Also, you can buy magnetic stick-on inclinometers. I use it to set the camber (roughly) as it was prior to disassembly when bolting a knuckle back onto a MacPherson strut car. The inclinometer has accelerometers and measures the direction of the gravity vector. Take out the spring, support the suspension by a floor jack (go up in increments of suspension compression), stick the inclinometer on the hub face, and start measuring camber! Another approach if your Fiero is running is to drive the car, then decide if you want more or less caster, based on your feeling. Geometry/math doesn't mean a thing unless you can relate the numbers to what you feel behind the wheel.

Luckily that diagram with the kingpin angle saved me from all of that (lol)

"Another approach if your Fiero is running is to drive the car, then decide if you want more or less caster, based on your feeling. Geometry/math doesn't mean a thing unless you can relate the numbers to what you feel behind the wheel"

You are EXACTLY correct. I just want to do BOTH that way I can relate the changes in feel that I notice to the objective changes in geometry that occured.

BTW I am in love with the way the car feels now. (Its my daily)

[This message has been edited by guitarfreak235 (edited 02-10-2017).]