Real Fiero Tech

befarrer wrote:Well, looked at the front a-arms, they are not on backwards, compared it to 2 other Fieros, they are also stamped L and R. I did grind the ball joint hole out alittle because the ball joint was hitting the large hole, preventing the ball joing from going all the way negative, now I am at about 0 degrees camber, and still alittle positive on the other side, the crossmember appears straight from all angles.

I dont know if this is bump steer or not, but when I drive over pot holes, man holes, etc that have a decent lip on them (which is every 12 feet in Edmonton), I can feel the car pull to that side, well, more like steer to that side. It also does this if one side of my car goes over an icy section of road, or a more slippery section (like a painted arrow that is wet). I did have it on the road last October when we started getting snow, and on an icy road, I had a hard time keeping the car straight on a straight road coasting at 20MPH, but I then had a few degrees toe out on the front, and a degree or two toe out on the rear, and all season tires, so that is probably why.

There is your problem, the rear needs Toe in, not toe out. Running Toe out ( negative toe ) on the rear with all that negative Camber makes for a very small contact patch on the inside edge of the tires and both rear tires are fighting each other to head for either ditch.

Take a tire, lean in on one edge and roll it, the tire will actually roll in a curve. Thats what's happing in back of your Fiero.

You will know what Bumpsteer is if you ever experiance it, I've been driving these daily since '89 and I've only experianced it twice, it's fucking dangerous scary. What happens is the quick extension of the rear strut on rebound from full compression will actually lift the rear of the car giving negative toe and you loose grip in the rear. In my cases, both times it was in the same corner at a high rate of speed. This particuliar corner has a drop part way through.
I felt the rear of the car lift and take off with a mind of it's own and heard the rear tires squeeling for grip when it started to grip again.

Edited to correct myself.............

The Dark Side of Will wrote:How do you make sure the straight edge is parallel to the centerline of the car (the bodywork is not)?

The straightedge is the same lenght of the car, so it touches both wheels on the same side at the same time.

Both wheels could still be pointed the wrong way...

Oh wait, I get it. If they were not true, they could be parallel, but would still not line up on a straight edge.

That sounds like it should work?

befarrer wrote:

The Dark Side of Will wrote:How do you make sure the straight edge is parallel to the centerline of the car (the bodywork is not)?

The straightedge is the same lenght of the car, so it touches both wheels on the same side at the same time.

Accounted for front/rear track differences down to not more than 1/8"?
A home grown alignment *can* be done, but not by assuming that your car starts off straight.

I think I may have found out the jumping around issue. The rear suspension bolt on the drivers side wheel was broken, allowing the wheel to move forward and backwards 3/4", and also, my front lower ball joint on the passenger side was loose in the a-arm, giving that wheel 1/4" movement. Tack welded the ball joint in, and replaced the bolt, and hopefully it will be normal.