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VALVE SPRINGS

UNCONDITIONAL LIFETIME WARRANTY ON ALL KNIGHT PROWLER VALVE SPRINGS!

Over 16 years of Over-the-Road testing by thousands of EVO and Twin Cam Engines with valve lifts of up to .750 lift has resulted in NOT ONE SINGLE REPORTED FAILURE OR LOSS OF SEAT PRESSURE WITH ANY KNIGHT PROWLER VALVE SPRING!
WE DON’T COPY AND WE DON’T IMITATE!

Every spring that is manufactured for our KNIGHT PROWLER Cams comes
from PSI with wire that is made from the highest quality Chrome-Silicone alloys. 
The hard to find rod material for these alloys is 100% Kobe steel, long considered
necessary to manufacture the cleanest, purest valve spring available in the world. KNIGHT PROWLER Valve Springs have an optional, proprietary, multi-step, surface enhancement process that has been proven to increase a spring’s endurance limit.  This process can be applied to any level of the
KNIGHT PROWLER series of springs. It is a very beneficial process for those looking for an increase in endurance while maintaining their existing setup.

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MILWAUKEE 8

BW-4V VALVE SPRINGS & TITANIUM RETAINERS

BW-4V

1.585 = 84 LBS

1.535 = 113 LBS

.985 = 260 LBS

.925 = COIL BIND

RECCOMENDED FOR: WM8-4860, WM8-9960, WM8-9F60, WM8-68, WM8-6860, WM8-408,

WM8-222, WM8-777 & WM8-999

EVO OR TWIN CAM

W160-PSW-10L
    Outside Dia.  =  1.445
     1.850  =  160lbs.
     1.800  =  180lbs.
     1.775  =  190lbs.
     1.200  =  430lbs.
     1.040  =  Coil Bind

W188-1200-10L
Outside Dia.  =  1.445
1.850  =  188lbs.
1.825  =  198lbs.
1.800  =  208lbs.
1.200  =  450lbs.
1.060  =  Coil Bind

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FOR ALL 2005 - 2017 TWIN CAM ONLY

 W160-PSW-7L

Outside Dia = 1.400
1.900 = 170lbs
1.875 = 178lbs
1.850 = 187lbs
1.300 = 368lbs
1.230 = Coil Bind

STOP! 2005 & up T-Cam Heads are different from 2004 and earlier heads.  Valve Springs are Bee Hive type with only 100lbs on the seat and have 7mm valve stems.  1.800 Int and 1.575 Ex valves
That Rotate Inside the Valve Locks.

EVO OR TWIN CAM 

W200-1200-10L
Outside Dia.  =  1.475
1.850  =  200lbs.
1.825  =  210lbs.
1.800  =  220lbs.
1.200  =  450lbs.
1.020  =  Coil

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