[C1] C1 Front end alignment caster shims
Thread Starter
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From: Cottonwood AZ
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C1 Front end alignment caster shims
I had it "recorded" somewhere but can't find it now.
There are shims made for adding caster to C1s which is recommended when using radial tires.
What are these called and where can you find them?
There are shims made for adding caster to C1s which is recommended when using radial tires.
What are these called and where can you find them?
Racer
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Thread Starter
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From: Cottonwood AZ
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Racer
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They go between the frame and front crossmember. The early C1's didn't have them. The later models got the shims.
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St. Jude Donor '07
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No caster difference between radial and bias-ply tires. More caster= more steering effort when the vehicle is parked or moving slowly, and it also adds high speed stability and better steering wheel return to center. Radial tires will increase steering effort when parked or moving slowly due to their increased footprint and construction. (bigger footprint)
Thread Starter
Race Director
Joined: Nov 2003
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From: Cottonwood AZ
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No caster difference between radial and bias-ply tires. More caster= more steering effort when the vehicle is parked or moving slowly, and it also adds high speed stability and better steering wheel return to center. Radial tires will increase steering effort when parked or moving slowly due to their increased footprint and construction. (bigger footprint)
Race Director
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Extra shims for extra caster will do just that. And radials, with bigger footprints, may indeed need a bit more help returning to center. Sounds like you are right on track, pun intended.
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St. Jude Donor '07
more caster, up to about 5 degrees, helps with return to center and straight ahead stability; especially important if you add power steering.
Bill
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I use two shims on each side of my car. With the slight rake from having the rear end sit a up a bit, it gets me into the 2.4*-2.5* caster range.
Some of the cross member bolts can be bitch to get out if they are original. having the bumper brackets off helps, IIRC.
PS the thick end goes to the rear.
Doug
Some of the cross member bolts can be bitch to get out if they are original. having the bumper brackets off helps, IIRC.
PS the thick end goes to the rear.
Doug
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Also, when I went to change my shims about 1995, the original shims were barely there. Galvanic corrosion on the shims made them partially disappear, even though my frame is about as rust free as any I have seen.
IIRC, I believe there was also the remnants of some insulating piece of thin ultra dense paper between the shims and frame top and bottom.
Doug
IIRC, I believe there was also the remnants of some insulating piece of thin ultra dense paper between the shims and frame top and bottom.
Doug
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and just FYI 53-55 did not have them
I "think" they were first added in 56...
I "think" they were first added in 56...
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Still, I find it curious that only '56s which are unstable about 50 MPH and which fall within a limited VIN range are specified.
Team Owner
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FWIW, my '54, which doesn't have the shims obviously, is stable to at least 75 mph. Too, with little caster, it's easy to steer at low speeds.
Still, I find it curious that only '56s which are unstable about 50 MPH and which fall within a limited VIN range are specified.
Still, I find it curious that only '56s which are unstable about 50 MPH and which fall within a limited VIN range are specified.
I do note that there are a number of parts listed in this TSB. I wonder if cars before 3175 would not accommodate some of these parts.
I don't know why that would be.
Puzzling.