The 72 Demon Follies....
Time for an update....
I finally got around to working on the car after having the one small rust area addressed. Recall that this car is originally from southern Texas so it is very clean underneath. But even so, it had the typical small rust area where the driver side rocker meets the quarter panel. So that got fixed and now it was time to get after the front suspension.
As previously shown, I got the SPC adjustable UCA's for it from member Bergman Autocraft. I worked all day Saturday taking out the old standard arms and installing these. They went in without too much fuss. Of course, getting the upper ball joints to let go of the spindles is never fun but the little spreader tool I have gave it all it had and each side let go with a loud POP when they finally let go! So the old arms were removed and the new ones installed. But since the brake lines had to be removed, I had the joy of having to bleed the front brakes. Never a good time but they actually bled fairly easily...knock on wood!
Then on to the alignment to see if my caster problems could now be resolved. And to test my knowledge to see if I could actually align the thing given all this adjustability!
The first thing was to come up with a good way to be able to discern the 20 deg steering angle in each direction to measure the caster. I made a v-shaped adjustable wooden fixture with a hinge that I used to set up my reference points. Since the front and rear tires are different sizes, I couldn't use the string method to determine exact/perfect 0 deg steering angle but I think what I did came pretty close. I used the fixture to mark tape I put on the floor to get 20 deg in each direction for each front wheel. Then I turned the steering wheel and put a 5' level along the front tire. When the level was parallel to my fixture, I knew I had 20 deg. It probably does not make as much sense on here as it did if you were in the garage with me as it's really just some old-school hotrod/backyard mechanic type of work. Sorta "use watcha got available!" Oh, and I use heavy plastic trash bags folded over multiple times as my front wheel turn plates as they really do slide on each other/allow the wheels to turn quite effortlessly.
Keep in mind that before, the best caster readings I could get were about -0.8 deg on one side and -0.5 deg on the other. Yep that's right, NEGATIVE caster! Scary stuff and sometimes at the track the car did feel like the proverbial shopping cart front wheel wobble!! With these new UCA's, you lengthen/shorten both the front and rear "arms" to get the camber you want and vary front vs rear to get the caster you want. Easy right? Well, like most things...kinda. But after a couple tries to gain a feel for the magnitude of the change available, it actually was relatively easy to set up. I set them where I wanted it and then set the toe-in to 1/8" at static height. I then reconfirmed caster/camber and set off on a 10 mile drive (always a pleasure as there always seems to be some idiot you have to ignore who pulls next to you and thinks you're at the track!), and came back to remeasure/confirm. I wanted to let the bushings "settle in" a bit before finalizing everything. I found one side needed a little tweak. Did that and locked it all down. I still have to decide/measure the toe-in through the front end lift travel and set it to the best compromise but I've done that before and know it ain't great no matter what!
So I'll shake it down a bit more this week and hopefully get to the track soon. I have new rear shoes coming for it this week (M/T 28/10.5-15W slicks) as that is what has been on the car and works. The old ones are shot and time for new! And ouch...expensive!! Probably wider than needed for a low 11-sec car but hey, they work and I sure don't want to guess wrong and get a radial or narrower tire that doesn't hook every time!!
So for alignment, and per my measurements, I have it set at Left/Right:
Camber = -0.3 / -0.3 deg
Caster = +3.2 / +3.0 deg
I went a little more on caster just to be certain I had sufficient POSITIVE caster!! Steering effort was not bad at all.
Out with these:
And in with the new (the jam nuts and bolts were locked down when I was done):
I'll update this when I have some new info. Until then, the Demon follies continue!!
Time for an update....
I finally got around to working on the car after having the one small rust area addressed. Recall that this car is originally from southern Texas so it is very clean underneath. But even so, it had the typical small rust area where the driver side rocker meets the quarter panel. So that got fixed and now it was time to get after the front suspension.
As previously shown, I got the SPC adjustable UCA's for it from member Bergman Autocraft. I worked all day Saturday taking out the old standard arms and installing these. They went in without too much fuss. Of course, getting the upper ball joints to let go of the spindles is never fun but the little spreader tool I have gave it all it had and each side let go with a loud POP when they finally let go! So the old arms were removed and the new ones installed. But since the brake lines had to be removed, I had the joy of having to bleed the front brakes. Never a good time but they actually bled fairly easily...knock on wood!
Then on to the alignment to see if my caster problems could now be resolved. And to test my knowledge to see if I could actually align the thing given all this adjustability!
The first thing was to come up with a good way to be able to discern the 20 deg steering angle in each direction to measure the caster. I made a v-shaped adjustable wooden fixture with a hinge that I used to set up my reference points. Since the front and rear tires are different sizes, I couldn't use the string method to determine exact/perfect 0 deg steering angle but I think what I did came pretty close. I used the fixture to mark tape I put on the floor to get 20 deg in each direction for each front wheel. Then I turned the steering wheel and put a 5' level along the front tire. When the level was parallel to my fixture, I knew I had 20 deg. It probably does not make as much sense on here as it did if you were in the garage with me as it's really just some old-school hotrod/backyard mechanic type of work. Sorta "use watcha got available!" Oh, and I use heavy plastic trash bags folded over multiple times as my front wheel turn plates as they really do slide on each other/allow the wheels to turn quite effortlessly.
Keep in mind that before, the best caster readings I could get were about -0.8 deg on one side and -0.5 deg on the other. Yep that's right, NEGATIVE caster! Scary stuff and sometimes at the track the car did feel like the proverbial shopping cart front wheel wobble!! With these new UCA's, you lengthen/shorten both the front and rear "arms" to get the camber you want and vary front vs rear to get the caster you want. Easy right? Well, like most things...kinda. But after a couple tries to gain a feel for the magnitude of the change available, it actually was relatively easy to set up. I set them where I wanted it and then set the toe-in to 1/8" at static height. I then reconfirmed caster/camber and set off on a 10 mile drive (always a pleasure as there always seems to be some idiot you have to ignore who pulls next to you and thinks you're at the track!), and came back to remeasure/confirm. I wanted to let the bushings "settle in" a bit before finalizing everything. I found one side needed a little tweak. Did that and locked it all down. I still have to decide/measure the toe-in through the front end lift travel and set it to the best compromise but I've done that before and know it ain't great no matter what!
So I'll shake it down a bit more this week and hopefully get to the track soon. I have new rear shoes coming for it this week (M/T 28/10.5-15W slicks) as that is what has been on the car and works. The old ones are shot and time for new! And ouch...expensive!! Probably wider than needed for a low 11-sec car but hey, they work and I sure don't want to guess wrong and get a radial or narrower tire that doesn't hook every time!!
So for alignment, and per my measurements, I have it set at Left/Right:
Camber = -0.3 / -0.3 deg
Caster = +3.2 / +3.0 deg
I went a little more on caster just to be certain I had sufficient POSITIVE caster!! Steering effort was not bad at all.
Out with these:
And in with the new (the jam nuts and bolts were locked down when I was done):
I'll update this when I have some new info. Until then, the Demon follies continue!!
