PRW 33 PQ Series Aluminum SB Chevy Shaft Mount Rocker User Manual

Page 2

Shaft Rocker Arm System Preparation:

Please read these instructions carefully before beginning your installation. Also, take a moment to
review the limited warranty information. If there are any questions or problems during the installation,
please do not hesitate to contact the PRW Customer Service Hotline at 1-888-377-9779, between the
hours of 7 a.m. and 5 p.m. PST Monday through Friday.

Make certain that you have all the tools necessary to complete the project.

Confirm that all parts are included by comparing to the parts list.

Assembly lube and/or lubricating oil should be readily available for installation.

Shaft Rocker Arm System Installation:

Step 1: The rocker arm roller tips must be immersed in oil for at least 3 hours prior to installation. This
will allow full lubricant penetration of the roller tip and axle. A disposable aluminum baking pan works
well for this purpose.

NOTE: It is critical to thoroughly pre-oil all shaft rocker components prior to use.

Step 2: Thoroughly inspect both cylinder heads to ensure that there are no obstructions that may impair
the rocker stands from bolting into place on an even plane.

Step 3: If installed, remove any rocker arm studs from the cylinder heads. The four (4) head bolts
located in line and between the rocker studs must be replaced with the low head cap screws provided.
Inspect all rocker stud bolt holes to ensure that the threads have not been damaged during removal of the
studs. Utilize a thread chaser to assure the threads are clean and to mount the rocker stands securely to
the cylinder head.

Step 4: Verify that all rocker stand bolts can be threaded to operational depths through the rocker shafts
and into the rocker arm stud holes, prior to applying torque to any of the rocker stand bolts. Confirm
adequate depth for rocker stand bolts with calipers or depth gauge. Check rocker arm shaft bolts to be
certain that none extend beyond the depth of the rocker arm stand when installed should be shortened
using a bench grinder. Be sure to clean up any modified threaded bolt ends with a thread chaser after
grinding.

Step 5: If longer than stock valve stems are being utilized, rocker stand shims will be required. If
required, make certain to utilize four (4) equal thickness combinations of shims under each pair of
rocker stud holes. Three (3) thicknesses of rocker arm pedestal shims are included (.100”, .050”, and
.025”) and eight (8) each are included with each kit. Carefully inspect the rocker arm geometry to
ensure that the roller tip is centered (or slightly over center) and nearly parallel to the valve spring
retainer. Shims should be added under the rocker stand to raise the shaft proportionate to the added
length of the valve stems. Shimming the heads may not be required if cylinder heads are equipped with
standard length intake and exhaust valves.

Special Note: For valve lift greater than .650” for small block Chevy and Ford, the shaft height
should be lowered by half the difference between actual lift. For less lift, the stand height should be
raised by half the difference between the above noted lift and actual lift. (i.e. for a small block with
.750” of valve lift, the rocker shafts should be .050” lower. For a small block with .600” of valve lift,
the rocker stands should be .025” higher.).

Step 6: Torque the 7/16” low head cap screws and all other head bolts to OEM or cylinder head
manufacturer’s specifications. Torque the 7/16” rocker arm stand bolts to specifications provided on
Page 3. Any bolts that thread into an intake runner should be coated with a thread sealant such as
Loctite®. Installation without shims may require filing .020”-.025” from the overall length of the
pedestal hold down bolts to prevent them from “bottoming-out” in some cylinder heads.