COMP Cams Ultra Pro Magnum XD Roller Rocker Arms - Manual (Page 3)

3
COMP Cams®
3406 Democrat Rd.
Memphis, TN 38118
Phone: 901.795.2400
Part #151
Revised 7/9/14
Toll Free: 1.800.999.0853
www.compcams.com
8. Adjusting exhaust valve: To adjust exhaust valves, turn the engine over until the intake pushrod moves all the
way up. Rotate past maximum lift, approximately 1/2 to 2/3 of the way back down. The exhaust lifter is now on
the base circle and the exhaust valve can be adjusted.
Hydraulic Lifter Cam: Rotate the exhaust pushrod with your fingers and begin to tighten the exhaust
polylock. When you feel the resistance on the pushrod, you are at zero lash. Rotate the polylock 1/2
turn more OR follow your specific lifter pre-load instructions. Go through the exhaust valves and repeat
the procedure carefully. Now all of the valves are adjusted with the proper pre-load.
Solid lifter Cam: Tighten the polylock, with the proper feeler gauge between the roller tip and valve, to
the point at which there is a slight drag when moving the feeler gauge. Hold the polylock with the
wrench and tighten set screw. Following this procedure carefully adjust all exhaust valves.
9. Before the valve covers are installed, be sure to pour engine oil on the rocker arms, making sure to coat the
roller tips. This will be extra assurance that the rocker arms will have adequate lubrication until the oil travels up
from the motor.
Special Instructions:
1. The use of old pushrods may result in pushrod or rocker arm failure. It is necessary to install new pushrods with
your new Ultra Pro Magnum™ or Ultra Pro Magnum™ XD Roller Rocker Arms to ensure your rocker arm
warranty. Pushrod ends have a mated surface to the rocker arm ball socket, much like a cam and lifter mate to each
other. This is why used pushrods should not be run with the new Ultra Pro Magnum™ or Ultra Pro Magnum™ XD
Roller Rockers.
2. On racing applications with dual springs, the rocker arms should be removed and inspected after the first hour of
running time.
3. In some cases Ultra Pro Magnum™ or Ultra Pro Magnum™ XD Roller Rockers will not fit under stock valve
covers due to the height of the polylocks or width of the rocker arms. Most aftermarket tall valve covers will not
have any clearance problems. However, you should always check for interference.
Application Notes:
Chevrolet
1965 to Present 396-454c.i.
Part #1620 and 1820. When installing your rockers, check your new pushrods to make sure they fit your guide plates.
Chevrolet has used 3 different pushrod diameters on production big blocks - 5/16", 3/8"and 7/16". Be sure to check for
valve spring coil bind, as this is a major problem area for Big Block Chevrolets.
Warning: Always Check the Following Before Operation!
• Old pushrods should not be used.
• Immediately upon startup rocker arms must have adequate oil supply.
• Check pushrod to cylinder head slot clearance.
• Check rocker arm to valve spring retainer clearance.
• Check for valve spring coil bind. If this occurs, the correct spring must be installed.
• Be sure to check for proper rocker geometry.