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Although ive never measured before putting them on, the red (steeda) bushings im sure are 92a-95a range. Ive never done the scp bushings.
 

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Now to add to this question. :D

I'm just throwing out numbers here for discussion's sake.

If you have a 95a bushing that is 1” cube and apply 1000 lbs of force to it (which would be 1000 lbs of force psi), it will deflect/compress by some amount, “x”.

If you have an 85a bushing that is 2” x 1” x 1” and apply 1000 lbs of force (to the whole 2” section) (i.e. it is laying flat and the force is applied downward)(which would be 500 lbs of force psi), it will deflect/compress by some amount, “y”.

Is x > y, or is x < y?

I think x > y because the 1000 lbs of force will be actually 500 lbs psi on the 85a bushing. So that even though the durometer rating is lower making it more flexible, the piece is dividing the load.

Thoughts, comments? :D
 

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Wait Wait Wait! Time on the field. The durometer test is a measure of penetrability and indentation and doesn’t necessarily correlate to durable ‘elastomeric’ strength. So back to the drawing board for you! :tongue:
 

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Urethane and polyurethane have an Elastic Modulus, just like other materials. Find the values and calculate the answer if you really want to know. These will be specific to the manufacturer of the product, but they ususally make this information available. Using some common values for E...

For 85 durometer, it usually falls around 4900 psi. For 95, it usually falls around 10000 psi. Using these numbers, 1000 psi load divided by 10000 psi E, gives a strain of .100 in/in. The other block with 500 psi load, divided by 4900 psi E, gives a strain of .102 in/in. Nearly identical deflection.

Mike
 

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Wait Wait Wait! Time on the field. The durometer test is a measure of penetrability and indentation and doesn’t necessarily correlate to durable ‘elastomeric’ strength. So back to the drawing board for you! :tongue:
Yes, the test is, but the number is an indication of the hardness, which is related to elastomeric strength.

So... :tongue:

Shore durometer, elastomeric strength, Elastic Modulus, stretchiness, squishability, etc.... still pretty much indicating the same thing for my application. :zwall:

But in any case, Toombs answered my question that different hardness can be used for the same purpose assuming the load area is adjusted accordingly.

I'm looking at two busings, one 88a the other 92a to 95a. I just wanted to know if their load bearing capabilites would be basically equal simply by varying the load area.:D

Thanks for the info everyone. :thumbsup:
 

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I bought a set from Energy suspension last year when I did my rear shafts they were the best 85.00 I have ever spent.
 

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I bought a set from Energy suspension last year when I did my rear shafts they were the best 85.00 I have ever spent.
you paid about $50 too much. My steedas were only 36$.
 

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I don't worry about the price of things, all I know is they worked as they should have and did not take that long to install.

The only bad thing I can say about the Energy suspension polyurethane is it's a solid block instead of the two halves, so it takes some real pressing to get them in.
 
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