COMP Cams COMP4-102 User manual

COMP Cams®
3406 Democrat Rd.
Memphis, TN 38118
Phone: [phone] Fax: [phone]
www.compcams.com Part # COMP4-102
Revised 7/10/06
Camshaft Installation and Degreeing Instructions
4.6-Liter 4 Valve Engines
Thank you for choosing COMP Cams® products; we are proud to be your manufacturer of choice. Please read
this instruction sheet carefully before beginning installation, and also take a moment to review the included
limited warranty information.
This instruction sheet is broken down into several categories for ease of use. Some of the topics may not apply
to every application, but all of the information will be very beneficial during the cam installation process. If
there are any questions or problems during the installation, please do not hesitate to contact the toll free CAM
HELP® line at 1-800-999-0853, 7 a.m. to 8 p.m. CST Monday through Friday.
Camshaft Installation
Step 1: Prepare a clean work area and assemble the tools needed for the camshaft installation. The use of an
automotive manual is strongly recommended for help in determining which components must be removed from
your engine in order to expose the camshafts, camshaft sprockets and timing chain assembly. A good, complete
repair manual will save both time and frustration during the installation of your new camshaft set.
Step 2: Remove the intake manifold and valve covers from the motor.
Step 3: Remove spark plugs, crank pulley, damper and engine front cover.
Step 4: Remove the primary timing chains and outer camshaft sprockets.
Step 5: Remove the secondary timing chain assemblies after relieving the tension on the secondary drive
assembly by depressing the plunger and inserting a pin to lock it in place.
Step 6: Rotate the crankshaft keyway counterclockwise 90° from 12 o’clock (to about the 9 o’clock position).
Note that this step is vital in order to avoid contact between the pistons and valves while rotating the cams for
the purpose of rocker arm removal.
Step 7: Rotate the camshaft so that the heel of the cam lobe is positioned over the rocker arm that you wish to
remove. Using the appropriate rocker arm service tool, compress the valve spring and remove the rocker arm.
Repeat this process until all of the rocker arms have been removed.
Step 8: Once all of the rocker arms have been removed, unbolt and remove the cam towers. Be sure to keep
track of the order in which you removed the cam tower caps and cap bolts, as they are not all the same size.
Step 9: Remove the old camshafts. Liberally coat your new COMP Cams® camshafts with the supplied
assembly lube. It is a good idea to use an additional bottle of lube, available from COMP Cams® (Part #152) in
order to ensure that you have enough lubricant for a proper installation. This is very important as (unlike a
conventional small block) pre-lubing the modular motor is difficult without some type of pressurized external
oiling system.
Step 10: Tighten all of the cam tower bolts using factory torque specification and tightening sequence. Verify
that each camshaft spins freely without binding (note that slight resistance to turning is normal).
INSTRUCTIONS

COMP Cams®
3406 Democrat Rd.
Memphis, TN 38118
Phone: [phone] Fax: [phone]
www.compcams.com Part # COMP4-102
Revised 7/10/06
Step 11: Position the crankshaft keyway at 12 o’clock, lock the camshafts (keyways facing down) and attach the
secondary camshaft gears and timing chains, making sure that the timing marks on the secondary gears line up
with the copper coated links on the secondary timing chains. Return tension to the secondary timing chains by
removing the pin that was inserted in step 5.
Step 12: Attach the primary camshaft gears and timing chains, making sure that the timing marks on the
camshaft and crankshaft gears line up with the copper coated links on the primary timing chains.
Step 13: Torque the camshaft bolts to the factory specification. Return tension to the timing chains following the
factory recommended procedure.
Step 14: Reinstall the rocker arms using the reverse of the procedure outlined in step 6.
Useful Part Numbers*
4.6L 4 Valve Camshaft
G
Camshaft Gear
S
12mm Camshaft
Blt
Cam Bolt Washer
F8AZ-6256-AA (RH) F1AZ-6278-A F1AZ-6A340-A F1AZ-6278-A
F8AZ-6256-BA (LH) Secondary Drive Gear 4V →F8ZZ-6256-AA
* Note that these are Ford factory part numbers, not COMP Cams® part numbers.
Camshaft Degreeing Procedure
The purpose of degreeing a camshaft is to ensure that it is phased correctly with the crankshaft. Some factors
that may cause improper phasing are:
•Camshaft or crankshaft gear marked incorrectly
•Incorrectly machined cam or crank gear keyways
•Misindexed cam keyway or dowel pin
•Improper machining of camshaft or crankshaft
•Accumulation of machine tolerances
The important factor to remember is that correct camshaft phasing is critical for efficient engine operation.
COMP Cams® offers all the equipment needed to properly degree in a camshaft, which includes the following:
•Degree wheel, COMP Cams® Part #4790
•Rigid pointer that can be attached to the engine block, COMP Cams® Part #4794
•Dial indicator with enough range to measure full cam lift, COMP Cams® Part #4909
•Magnetic or attachable base to affix the dial indicator, COMP Cams® Part #4907
•Top dead center stop, COMP Cams® Part #4795
•A means to attach the degree wheel to the crankshaft –COMP Cams® Pro Crankshaft Socket (Part
#4798) works very well for this purpose, as it provides a convenient means of rotating the engine in
addition to firmly anchoring the degree wheel in place.
Also required in order to degree your new COMP Cams® 4.6-liter camshafts are a 1” wrench, and solid valve
adjuster (lifter).

COMP Cams®
3406 Democrat Rd.
Memphis, TN 38118
Phone: [phone] Fax: [phone]
www.compcams.com Part # COMP4-102
Revised 7/10/06
Intake Centerline Method
There are several accepted ways to degree a camshaft. COMP Cams® suggests the intake centerline method as
the easiest and most accurate. This method of cam degreeing is very practical and indifferent to engine design
characteristics. It simply involves positioning the center, or point of maximum lift, of the #1 intake lobe with
Top Dead Center (TDC) of the #1 piston. The intake centerline method still requires accuracy to be correct, but
it is somewhat forgiving. Once you have degreed a camshaft using this method, you will be surprised at its ease.
Step 1: The camshafts and timing chains have been installed. Make sure that the timing marks on the cam and
crank gears are aligned properly with the copper coated timing chain links as per the camshaft installation
instructions.
Step 2: Position the #1 piston at Top Dead Center (TDC). Attach the degree wheel to the balancer or crank
socket, and install the assembly on the crankshaft. The crank may be rotated from either the front or from the
flywheel end. Obviously, if the engine is in the car, you must rotate from the front. Remember, the greater the
leverage, the smoother the crank rotation and the more accurately you can rotate the crankshaft. Install degree
wheel and pointer and set the pointer to zero on the degree wheel. Note: Never use the starter to turn the
engine while degreeing a cam.
Step 3: Rotate the crankshaft opposite the engine rotation direction about 15-20 degrees. This will lower the
piston enough to permit the installation of the piston stop in the #1 spark plug hole. Rotate the crankshaft
clockwise until the piston hits the stop, and record the number indicated on the degree wheel. Next, rotate the
crankshaft counterclockwise until the piston hits the stop from the other direction, and again record the number
on the degree wheel.
Step 4: Remove the piston stop after marking the two points on the degree wheel. Rotate the crankshaft to the
midpoint of the two marks (this is determined by adding the two points that you marked on the degree wheel
together, then dividing by 2). This point is TDC for cylinder #1.Without rotating the crankshaft adjust the degree
wheel to read 0 degrees at the pointer. You are now ready to locate the exhaust lobe centerline relative to TDC.
If you are not absolutely sure that your zero degree mark is set at TDC, repeat this procedure. This step is
critical to proper camshaft alignment.
Step 5: Attach the dial indicator to the dial indicator mount. Position the dial indicator mount so the tip of the
dial indicator extension/plunger will contact the retainer of the #1 exhaust valve spring. Note that although this
is the “intake centerline” method, the exhaust cam drives the intake cam on a 4.6-liter 4 valve engine, which
necessitates verifying the exhaust centerline first. It is important that the indicator plunger be parallel to the
valve stem. Any variance in the angle of the indicator will introduce geometric errors into the lift readings.
Step 6: Rotate the clockwise until the camshaft reaches maximum exhaust lift. The dial indicator will begin to
change direction at the point of maximum lift. At this point, set the dial to zero.
Step 7: Rotate the crankshaft counterclockwise until the dial indicator reads .100”. Next, turn the engine
forward in the normal direction of rotation until the dial indicator reads .050” before maximum lift. Record the
degree wheel reading.
Step 8: Continue to rotate the engine over in its normal direction of rotation until the indicator goes past zero to
.050” on the closing side of maximum lift. Again, record the degree wheel reading.
Step 9: Add the two numbers together and divide by 2. The resulting number will be the location of maximum
lift of the exhaust lobe in relation to the crank and piston. This is the exhaust centerline. For example: The first
degree wheel reading was 106 degrees. The second reading was 130 degrees. These two numbers (106 + 130)
added together will be 236. 236 divided by 2 will equal 118. Your actual exhaust centerline is 118 degrees.
Verify that your measured exhaust centerline matches that listed on your camshaft specification card.

COMP Cams®
3406 Democrat Rd.
Memphis, TN 38118
Phone: [phone] Fax: [phone]
www.compcams.com Part # COMP4-102
Revised 7/10/06
Step 10: Repeat the degreeing process on the intake camshaft.
Step 11: Repeat the degreeing process on the opposite cylinder bank, this time using the number 6 exhaust and
intake valves to check lift centerline. Note that it is not necessary to reestablish TDC in order to verify the #6
intake and exhaust centerline.
In the event that your camshaft did not degree in to the camshaft specification, it will be necessary to either
advance (move the cam ahead) or retard (move the cam back) the camshaft to meet the suggested intake/exhaust
centerline. There are generally a couple of degrees of advance/retard available by loosening the timing gears
(lock the camshafts again before loosening the bolts!) and rotating the crankshaft until the pointer is positioned
at the desired intake/exhaust centerline reading. Refer back to step 9 if you do not remember how to determine
that reading. Note that any changes that you make to the intake centerline will require re-verification and
adjustment of the exhaust centerline.
Note: When degreeing a cam, remember to look at the degree wheel as two 180 degree sides, no matter
how the degree wheel you are using is marked. Many degree wheels are marked in 90 degree increments.
On wheels that are marked in 90 degree increments, keep in mind that you must continue to count the
number of degrees on past 90 degrees. Be sure all readings are taken from Top Dead Center.
Keep in mind that to advance the cams, you must lower both the intake and exhaust centerline. For example, if
your camshaft set has a lobe separation of 114 degrees, moving the intake centerline to 110 degrees advances
the cam set 4 degrees. Conversely, moving the intake centerline to 116 degrees retards the camshaft set 2
degrees. Note that it is very important that with the 4.6-liter 4 valve engine, any advance/retard adjusted into the
intake cams must also be reflected in the exhaust cams.
Limited Warranty
Competition Cams, Inc. warrants that all of its products are free from defects in material and workmanship, and
against excessive wear for a period of (1) one year from the date of purchase. This limited warranty covers the
original purchaser.
Competition Cams, Inc.’s obligation under this warranty is limited to the repair or replacement of its
product. To make a warranty claim, the part must be returned within (1) one year of purchase to the address
listed below, freight prepaid. Items covered under warranty will be returned to you freight collect.
It is the responsibility of the installer to ensure that all of the components are correct before installation.
We assume no liability for any errors made in tolerances, component selection, or installation.
There is absolutely no warranty on the following:
A) Any parts used in racing applications;
B) Any product that has been physically altered, improperly installed or maintained;
C) Any product used in improper applications, abused, or not used in conjunction with the proper
parts.
There are no implied warranties of merchantability or fitness for a particular purpose. There are no
warranties, which extend beyond the description of the face hereof. Competition Cams, Inc. will not be
responsible for incidental and consequential damages, property damage or personal injury damages to the extent
permitted by law. Where required by law, implied warranties or merchantability and fitness are limited for a
term of (1) one year from the date of original purchase.
This warranty gives you specific legal rights and you may also have other legal rights, which vary from state to
state.