Knowing suspension rubber would need to be replaced IF I ever put 5177 back together, I purchased the A-arm bushings

During another discussion today, I decided to check the length of the "stock" A arm bushings and the findings may be the quality I just received are less than desired.

The frame drawing shows the tabs should be 47mm -0/+.5 or 1.850" -0/+0.020”. I
Checked 4 of my removed A arms and yes the bushings are 1.850 +/- 0.005 (the tolerance of quickly checking with calipers)

However when I checked 8 of the 16 new ones and they were 1.850 +/- 0.040".
Yes, the ranged from 1.81 to 1.89!

Did I receive rejects? Or is this just a car and nothing to worry about.

When I get the time I plan to make better measurements and document the actual findings But before I confront the vendor, I would like to know what would be acceptable

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thanks...

your samples are more consistant than the ones I received.
just my guessing from the frame dimensions tolerance of 47mm -0/+0.5,
I would have expected the bushings to be spec'ed as 47mm -0.5/+0

which your samples easily fall into that range
where mine appear to be 47mm -1/+1.
I say appear, as was not very deliberate when I did make the measurements yesterday with a caliper.

Now that I have lost confidence in the quality of my new bushings I NEED to also check their diameter when I have to time to ensure my measurements are accurate with the use of mike's

UPDATE...

I measured all 16 I received. the first 8 I looked at that got me concern was a mixed assortment with some stamped ITALY and others with suspicious check marks.

the next 8 all appeared to be newly made and ALL measured a length of 1.830".

My next concern is the diameters...while the first 8 diameters were from 1.183 to 1.189. the second 8 are ALL 1.189"
Last edited by jfb05177
Measure the inside dimension of the yokes that bolt to the chassis.
These bushings are sort of a "press fit" into them and they compress as you "press" them in.

I'm using the poly bushings so I haven't dealt with the rubber ones in thirty years or so but as long as they are snug I think they are fine.

As I understand it, you car is apart. Just put one of the yokes in a vice on your work bench and take one of the shorter bushings and see how they fit vs. the longer ones.

You should need to use a rubber or hickory mallet to get them to fit.

My yoke measures 1.843" inside. If you have issues with some of yours being too loose, you could shim them with hardened shims like you would do on the brake calipers to center them on the rotor.
Last edited by panteradoug
It looks like a offset bushing? The offset designed to give you more caster, from 1* stock to 3 or 4*, that would explain the 8 bushing, they would be for the front. Just a guess based on your picture. The offset moves the upper a-arm back and the lower a-arm forward, if they are not offset, you might consider getting the offset type, it makes for much better steering / handling at speed.
If you consider all the dimensions of the offset bushings they give you an extra 1 to 1.5 degrees caster at most.

I modified my a-arms and have up to 7.5 degrees if desired. The wide body cars like 7 degrees and narrow body is best with 4-5 degrees.

Julian
the vendor has not responded to my emails about dimensions, However he did gracously SOLD me another 8 that appears to all be by the same manufactorer. there overall length was within what I consider the desired range of 47mm -0.5/0.

However, even from those new 8, there were two differnt ODs for the press fit. I can see that the A arms ID fits may be differnt so is it the practice to machine the bushing's OD to provide a given press OR do you just use what ever force is needed to put them in with out considering if the metal is stretched beyound yield

As for axial offset providing caster improvement;
given the seperation of the upper/lower arms is about 8.4", the bushings axial offset between the two arms would need to be 0.15" for just 1 degree
(tan 1) X 8.4 =0.147
From what I know, a "press fit" would have the od of the bushing at .001" smaller then what the id of the knuckle is.

.002 MIGHT be too loose. 0, would be too tight.

At some point the steel sleeve of the bushing would collapse like an accordion if the fit was too tight.

Put a flat plate over the lip of the steel bushing that covers the entire ring in order to press it in uniformly.

A "regular" hydraulic press should be fine. You might even be able to do it in a 4" or bigger bench vice?

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