Comp springs.

67coronetman

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I need a little help from you all out there can anybody tell me the uninstalled height difference.
On the comp springs 929-16

Compared to the comp spring 928- 16.
 

69Bee

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Comp doesn't list the free height. What do you need it for?
 

GTX JOHN

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I am also a bit curious why you want the uninstalled height or pressure unless you are going to put 2" Valves into the heads.
 

khryslerkid

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But it doesn't list "Free Length".

I'm not exactly sure what you mean by "Free Length". Is it the height of the spring just sitting there on the work bench?

Do these specs show anymore on Jegs add?
Screenshot_20211215-214907_Chrome.jpg

https://www.jegs.com/i/COMP-Cams/249/929-16/10002/-1
 

69Bee

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69Bee

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The "Free Length" is the measurement of the spring, uninstalled and sitting on the bench.
IMG_9582.jpg

IMG_9583.jpg
 

IQ52

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Using the pressure @ 1.850" installed height and the spring rates in the Comp Cams catalog, the free length of the 929 will be approximately 2.206" and the 928 will be approximately 2.333".

NOPE, that is not going to work as they are dual springs. I just tried those calculations on a 925 dual spring and got 2.181" and then measured the spring at 2.430". It would work if they were single springs.

Another brain fart!
 
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66Satellite47

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I never thought "free length" was of any concern. I have always been concerned with the spring pressure with the retainer I was using at a given installed height. I shim to get the pressure I want.
 
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