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  1. #11
    Quote Originally Posted by butterbean_29512 View Post
    If you have the retainers, and not turning higher RPM's, you are wasting a little horsepower due to the increased tension on the springs. The engine has to expend horsepower to turn things such as the camshaft, etc, and if you're expending extra horsepower without turning the extra PRM's it's a waste of power. Not much, and probably not enough to worry about, but it's still power not used to turn the impeller.
    he just got the titanium vale retainers and using stock valve springs...they are lighter and if anything...increase hp by very very little, if not none
    Last edited by yellow jacket; 11-11-2019 at 06:58 PM.

  2. #12
    Saum700p's Avatar
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    Taller impeller 13/20...


  3. #13
    outnumbered's Avatar
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    I have a 13/20 that Jim repitched to a 13/19. PM me if interested.

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