Recommended upgrades & modification tips – Zipper's Performance Red Shift Cams TC User Manual
Recommended Upgrades & Modification Tips:
Although some of the following topics are model year specific, perform these necessary tasks before you begin the actual re-
assembly process. Having all of the machine work completed, with the subassemblies ready to go will make the installation go
1.) Inner Cam Bearings
With the cam chest open, upgrade and replace the factory installed inner cam bearings. The highest quality, full-
complement Torrington® brand needle bearing is available for direct replacement. It is highly recommended that the
proper tools are used for damage-free bearing removal and installation.
2.) Test & Repair Cam Support Plate
The Cam Support Plate performs an array of functions, so it’s easy to overlook the Oil Pressure Relief Valve. Always
check for leaks at the Oil Pressure Relief valve if you have the cam support plate out of the engine. Even new in the box
plates must be checked before installing, many times new does not mean sealed.
3.) Blueprint & Repair Rocker Arms, Shafts, and Rocker Stand Supports.
Using the provided worksheet, inspect and determine the status of your rocker arm assemblies. Since these are
high pressure points of contact, it is critical that the tolerances are held within factory specs. Low oil pressure or a loss of
valve train control will immediately affect the condition of the rocker arm bushings.
Please research your options when repairing an out of spec rocker arm bushing. If you find more than one problem
on a single rocker arm, it may be cheaper to replace the entire rocker arm than repair it. A new rocker arm from the factory
comes with new bushings installed, sized for a standard rocker arm shaft, and is inexpensive. Although replacement
bushings alone are very inexpensive, if you have to replace both the pushrod and valve side bushings, the labor costs to
replace the bushings will exceed the price of a new rocker arm.
Once complete, wash all of the pieces of the rocker arm assemblies. Coat the rocker arm shafts with a high quality
assembly lubricant, and reassemble the rocker arm assemblies.
4.) Higher Quality Lifters
Replace your hydraulic lifters now!! Red Shift recommends that lifters be replaced with any new
cam installation; we strongly suggest lifters are removed for a full inspection of the rollers at or before 20,000 miles of use,
regardless of the brand of lifter or camshaft. Many skilled engine builders replace lifters at this mileage threshold because
they view the rollers as wear items; they are fully aware that waiting until failure will be extremely costly for your
engine. Any material shedding from the lifter roller or roller bearings can be a sign of a lubrication problem, which will
cause significant damage throughout the entire engine. Don’t let a part that’s inexpensive and easy to replace ruin your
5.) Higher Quality Pushrods
The majority of Red Shift cams are designed to be used with adjustable pushrods. Red Shift always recommends
stiffness over weight when discussing pushrods. Zipper’s sells a well proven “Pro-Taper” pushrod that is significantly stiffer
than a factory pushrod. Many new options are available, including heavy walled 3/8” straight pushrods that work extremely
well with factory installed springs, and have plenty of clearance between the pushrod and the pushrod tube.
6.) Red Shift Dual Piston Cam Chain Tensioners
The revolutionary new dual-piston design is so simple
and effective; it’s easy to see why it works. When the Twin Cam®
engine is running, the power pulses rock the tensioner shoe back
and forth. On a single piston tensioner design, the natural shoe
movement causes the hydraulic piston to momentarily unseat at
the base, which interrupts the pressurized oil stream and
introduces air into the hydraulic tensioner. Air will diminish or
eliminate the pressure that the tensioner shoe places on the cam
drive chains, allowing loss of valve train control - leading to
“bounced” components including valves, spring collars, rocker
arms, pushrods, lifters and camshafts.
Red Shift® Dual Piston Cam Chain Tensioners are designed with shoe and hydraulic
stability in mind, eliminating harmful air leaks in the cam chain tensioning system while
dramatically improving overall valve train control and durability.