HW Singles Cush Drive Springs

[Joker_Bones]

I have acquired a couple cush drive springs.
This one is 1/4" x 3/16" and I believe is an AMC part, it looks familiar.

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This one I picked up at a jumble without knowing what it was from. It is 3/8" x 3/16" with much more rounded edges.

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They both have the same ID and height and both fit the cam and cup washer.
Is the lighter one for a 350 and the other for a 500?
Does anyone recognise them from their dimensions/appearance?

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[clive]

With most of the springs I have seen the 500 is a little longer that the 350, uncompressed. My experience has always been if it is relatively easy to get the nut on its probably a 350 spring, more of a struggle with the 500. I guess the thicker one may be for a 500 as you suggest and because its shorter it would be easier to get the nut started.

[Joker_Bones]

Ahhh... I didn't know the 500 spring was longer.
I can start the nut on both of these springs by hand, so I imagine the lighter one which looks like an AMC spring is for a 350.
I don't know what the other is from, but it fits and is stiffer. The engine is a 500 so I'll try that one.

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