Coil bind

General engine tech -- Drag Racing to Circle Track

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Jeff Lee
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Re: Coil bind

Post by Jeff Lee »

Correct me if I am wrong, but doesn’t Porsche or Mercedes (or both?) set up there performance engines with near coil bind?
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68corvette
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Re: Coil bind

Post by 68corvette »

It relly depends onnthe herzian stress of the wire.
Different materials have different yield stress point.
If spring is not designed to allow low enough stress up to lift untill coilbind, then the service life can be drastically reduced.
If spring is running at its resonance point, then that will add more stress for the spring as running close to coilbind stabilizesthe spring.

But with some springs the maximum recommended lift can be far from coilbind and running the spring tighter will reduce the total cycle lifetime of the spring.

Though what I see is that most springs are now days designed to be able to run close to CB, but without knowing the material, diameter, amount of wounds and free length its just a guess work.
Or one can trust the manufacturer.

Giving recommendations to just run it to x from coilbind might be a total dicaster in some cases.
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