Snapping noise from SPC control arms (SC&C Stage 3 set up)..

[Sleeper68]

Thank you very much Ryan..

My street has a very high road crown, when I drive up the left side, the car drifts left, when I drive up the right side, the car drifts right.. So my issue looks like bump steer..

I added a little more +caster yesterday and took some of the - camber out. I have SPC adjustable uppers and did this by extending the front bar a half turn on both sides.. This seemed to help but I'm not there yet.. I am so happy I found that noise though!!

I'm taking it in for an alignment Tuesday. The local garage has a Hunter Hawk Eye rack and the tech seems to know how to run it. He aligns school busses all day so getting my el Camino is a joy to him.. I want to rule out the rear end so a four wheel alignment should help... I have the Spohn "Del Sphere" adjustable rear control arms..

MY 69 el Camino has SPC front uppers and lowers with Delrin bushings with tall .9 and .5 Howe ball joints. Lee 14:1 box with heavy feeling 30 lb valve and 13" steering wheel.

I was going to try these front end specs, what do you think?
Drivers side, +7 caster, -.25 camber, 1/16 toe in.
Passenger side, +7.50 caster,-.25 camber, 1/16 toe in.
or
Drivers side, +6 caster, -.25 camber, 1/16 toe in.
Passenger side, +6.50 caster,-.25 camber, 1/16 toe in.

How did you verify your home alignment? I doubt rear steer is the issue since the car will pull both directions.

I think the latter spec is better because the caster is less. Caster over 6° starts to get laborsome and unnecessary, although I would keep the cross-caster low. As you have said, it will pull left and right, depending on the location of the crown relative to the car. Biasing the caster may help with attenuating crown pull in some instances, but will hurt it in others.

I would run:

-0.5° to -1° Camber , +6° Caster , 1/16" toe-in.

Ryan

[pitts64]

I verify by using a digital angle finder.. I put my front wheels on greased sheet metal. I made a spot on my driveway that is level... I turn my wheels one whole turn, zero the angle finder, turn it one whole turn to the other side and check for caster.. Camber is simple just check the angle of the wheel from top to bottom. I have heavy chrome centers that are flat and make this very easy, right at the red cap in the photo..








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