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Valve spring question

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Old 03-01-2022, 07:57 PM
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jimih941
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Default Valve spring question

What is the max lift of the ls2 springs? I’ll be adding new rocker arms and am looking to install 1.8 or 1.85. Looking into reviews the 1.85 can get up to 0.6 lift. I am assuming I should upgrade the springs… will 0.6 be enough or should I go higher? Any cons to adding a higher lift spring?
Old 03-01-2022, 08:10 PM
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zanerwaner
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I always heard going from.1.7 to 1.8 added about 40 to your lift specs..so a stock 520 lift ls2 cam..would essentially be a 560 lift? Just spit balling things I've read not a pro..how are you gonna get around possible pushrod length difference or valve cover clearance issues using 1.8? I looked into this awhile back and could never sort it all out lol
Old 03-01-2022, 08:37 PM
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old motorhead
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Divide the valve lift of your current cam by 1.7. Multiply the result by 1.8 or 1.85 (depending on which ratio you choose) to get the ending valve lift. Choose a valve spring that is comfortable with that much lift.
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Old 03-01-2022, 10:59 PM
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Turbo6TA
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Want to know what your valve lift will be going from a 1.7 ratio rocker arm to a 1.8 ratio rocker arm ... Here is your calculator:

http://www.wallaceracing.com/rockercalc.php

You will see that it increases the lift approx .032" (32 thousands of an inch)
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Your stock valve springs are safe up to about .550" lift ... You would be better off replacing them with a set of PAC 1218 beehive single springs. These springs are safe up to .600" valve lift and are a drop-in replacement.

As far as needing a different length pushrod ... You should be able to use the stock length pushrods and maintain the correct lifter preload.

Here is a set of nice Comp Cams 1.8 ratio rocker arms for the LS2 and LS3 engine. These will be a drop-in 'full roller' replacement for your stock 1.7 ratio rocker arms ... Comp Cams P/N: 1678-16


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Old 03-02-2022, 09:44 AM
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jimih941
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Thanks everyone. Great feedback. Appreciate it

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