spring coil bind

[Saltillo Express]

I've spent the last hour or so trying to research spring coil bind specifically related to valve springs. I've got a general understanding of it - but - Can anyone walk me through exactly what it means and moreover - how to take a valve spring and calculate it? And last but not least - does shimming increase or decrease the point of coil bind? Are the 5.7 Gen 4 springs shimmed from the factory? What is the size of the shim? I know. Boring.

 

[Saltillo Express]

insightful. So in theory one could calculate potential coil bind by a formula that took into account the open and close pressure of a spring? But the close pressure of the spring is not coil bind. So? I'm trying to come to a formula by which I can check various springs for correct operation and figure how to avoid potential coil bind taking into account shims and cam lift, etc.

 

[catch 22]

You still have to know your assembled height of the valve and seat pressure, this is something that paper and pencil are not going to solve....you or your machine shop are going to have to take something apart.

 

[Saltillo Express]

also insightful. Would the stock spring assembled heights be readily available information? And isn't there a formula for calculating coil bind or the avoidance of it?

 

[Saltillo Express]

Thx man. I'm considering the Manley 221424 Nex Tek springs. The installed height is 2.00 in. However it doesn't say whether I leave the factory shims .038 or remove them. The lobe lift on the cam I'm considering is 353/333. Rocker Ratio is factory I believe at 1.65. What I don't know is the height of the spring fully compressed (coil bind). I guess I can call Manley on Monday. http://www.summitracing.com/parts/man-221424-16/applications