Approval Details

Valid E.O.


This Executive Order approved the specified parts on on October 1, 1992.
As of Wednesday, September 18th, 2019 this Executive Order has not been overturned or superceeded.

Approved Parts

Part NumberModels
12-305-41987 and older GM vehicles powered with a 267 CID to 350 CID carbureted V8 gasoline engine.

This Executive Order may be listed as:
  • C.A.R.B.E.O. D-279-1
  • Executive Order 279-1 / D279-1
  • ARB # D-279-1
  • Executive Order No: D-279-1
  • C.A.R.B. No. D-279-1
  • Resolution D-279-1
For Free CARB Executive Order Status verification, email an image of the device Executive Order label as well as the Year/Make/Model and Test Group # of the vehicle to [email protected]

Download: Executive Order D-279-1 PDF

D-279-1 Document:

                                                       (Page 1 of 2)

                            State of California
                            AIR RESOURCES BOARD

                          EXECUTIVE ORDER D—279—1
                 Relating to Exemptions Under Section 27156
                            of the Vehicle Code

                           COMPETITION CRMS,     INC.
                            PURE   ENERGY   CAMSHAFT
                               (P/N 12—305—4)
Pursuant to the authority vested in the Air Resources Board by Section 27156
of the Vehicle Code; and

Pursuant to the authority vested in the undersigned by Sections 39515 and
39516 of the Health and Safety Code and Executive Order G—45—5;

IT IS ORDERED AND RESOLVED:  That the installation of the Pure Energy
Camshaft, P/N 12—305—4, manufactured by Competition Cams, Inc. of 3406
Democrat Road, Memphis, Tennessee 38118 has been found not to reduce the
effectiveness of the applicable vehicle pollution control system and,
therefore, is exempt from the prohibitions of Section 27156 of the Vehicle
Code for 1987 and older General Motors vehicles powered with a 267 CID
{4.4L) to 350 CID (5.7L) carbureted V—8 gasoline engines.

This Executive Order is valid provided that installation instructions for
this Pure Energy Camshaft, P/N 12—305—4, will not recommend tuning the
vehicle to specifications different from those submitted by Competition
Cams,   Inc.

Changes made to the design or operating conditions of the camshafts, as
exempt by the Air Resources Board, which adversely affect the performance of
a vehicle‘s pollution control system shall invalidate this Executive Order.

Marketing of this camshaft using any identification other than that shown in
this Executive Order or marketing of this camshaft for an application other
than those listed in this Executive Order shall be prohibited unless prior
approval is obtained from the Air Resources Board.  Exemption of the
camshaft shall not be construed as exemption to sell, offer for sale,   or
advertise any component.of the kit as an individual device.

This Executive Order does not constitute any opinion as to the effect the
use of this camshaft may have on any warranty either expressed or implied by
the vehicle manufacturer.                   °


COMPETITION CAMS, INC.                            EXECUTIVE ORDER D—279~1
PURE ENERCY CAMSHAFT                              (Page 2 of 2)

No claim of any kind, such as "Approved by the Air Resources Board" may be
made with respect to the action taken herein in any advertising or other
oral or written communication.

Viclation of any of the above conditions shall be grounds for
revocation of this order.  The order may be revoked only after ten day
written notice of intention to revoke the order, in which period the holder
of the order may request in writing a hearing to contest the proposed
revocation.  If a hearing is requested, it shall be held within ten days of
receipt of the request and the order may not be revoked until a
determination after hearing that grounds for revocation exist.

Executed at El Monte, California, this    _/   day of October, 1992.

                                         AsSistant Division Chief
                                         Mobile Source Division

                          State of California
                          AIR RESOURCES BOARD


                              October 1992

                            State of California
                            AIR RESOURCES BOARD


                          Mobile Source Division
                            State of California
                            Air Resources Board
                            9528 Telstar Avenue
                             El Monte, CA 91731

(This report has been reviewed by the staff of the California Air Resources
Board and approved for publication.  Approval does not signify that the
contents necessarily reflect the views and policies of the Air Resources
Board, nor does the mention of trade names or commercial products constitute
endorsement or recommendation for use.)


     Competition Cams, Inc. has applied for an exemption from the

prohibitions of the Vehicle Code Section 27156 for their Pure Energy

Camshaft,   P/N 12—305—4,   for installation on 1987 and older General Motors

vehicles equipped with 267 CID (4.4L) to 350 CID (5.7L) V—8 gasoline engines

utilizing feedback or conventional carburetors.         Competition Cams has

submitted a completed application and all the required information, as well

as exhaust emissions test data performed at E. C. S. Laboratories, Inc.

which demonstrated that the Pure Energy Camshaft does not have any adverse

effect on the exhaust emissions of the affected vehiclés.            Testing performed

at the Air Resources Board (ARB) confirmed the test results.

     Based on the submitted information and the results of the emissions

tests performed at E. C.    S. Laboratories,   Inc.   and the ARB,   the staff

concludes that the installation of Competition Cams,        Inc.‘s Pure Energy

Camshaft, P/N 12—305—4, will not adversely affect exhaust emissions on the

specified vehicles.

     The staff recommends Competition Cams, Inc. be granted an exemption as

requested and that Executive Order D—279—1 be issued.

                               TABLE OF CONTENTS

                                                        Page Number


CONTENTS                                                     1i






           APPENDIX A     — Installation instructions




      Competition Cams, Inc. of 3406 Democrat Road, Memphis, TN 38118, has

applied for an exemption from the prohibitions of Vehicle Code Section 27156

for their Pure Energy Camshaft, P/N 12—305—4, for installation on 1987 and

older General Motors vehicles equipped with 267 CID (4.4L) to 350 CID (5.7L)

engines utilizing feedback or conventional carburetors.

      Competition Cams has submitted a completed application and all the

required information, as well as exhaust emissions test data performed at

E. C. S. Laboratories, Inc. which demonstrated that the Pure Energy Camshaft

does not have any adverse effect on the exhaust emissions of the affected

vehicles.   Testing performed at the Air Resources Board (ARB) confirmed the

test results of E. C. S§. Laboratories, Inc.

      The staff recommends Competition Cams,   Inc. be granted an exemption as

requested and that Executive Order D—279~1 be issued.


      Based on the submitted information and the results of the emissions

tests performed at E. C. S. Laboratories, Inc. and confirmatory testing

conducted at the ARB, the staff concludes that the Competition Cams,    Inc.

Pure Energy Camshaft will not adversely affect exhaust emissions from

vehicles for which the exemption is requested.


      The staff recommends that Competition Cams, Inc. be granted an

exemption as requested and that Executive Order D~279—1 be issued.


      The Pure Energy Camshaft, P/N 12—305—4, is specifically designed for

installation on 1987 and older General Motors vehicles powered by 267 CID

(4.4L} to 350 CID (5.7L) V—8 carbureted gasoline engines.     The camshaft

operate in conjunction with the original equipment manufacturer (OEM)

computer controlled feedback or conventional carburetors along with the

emission control systems already certified with the stock engines.     The

purpose of using the Pure Energy Camshaft is to increase the overall engine

performance which is a direct result of modifying the valve characteristics.

An example would be the increase in valve lift and duration.

      The Pure Energy Camshaft, P/N 12—304—4, increases the intake lobe lift

by 21,5 percent and increases the exhaust lobe by>14.0 percent when compared

to the OEM camshaft.   The installation instructions for the Pure Energy

Camshaft is located in Appendix A.


      A 1987 Chevrolet Camaro powered by a 305 CID engine was used for the

evaluation of the Pure Energy Camshaft.     Documentation given to Competition

Cams by General Motors indicated that a prom change would calibrate their

Camaro to California specifications.     This information was verified by

the ARB during the application process and confirmatory testing.                   The

dynamometer inertia weight and loading used during the testing were 3625

lbs. and 7.6 hp, respectively.

     Emission tests conducted by E.         C.    S. Laboratories,      Inc.   consisted of

cold—start CVS—75 emission tests with the Pure Energy Camshaft, P/N

12—305~4,   installed on the test vehicle.           This test was used to compare

vehicle exhaust emissions in the modified confiquration with the applicable

emission standards.     The test results are shown in Table 1.

                                          Table 1

                                  CVSs~75 TBST RESULTS

                          (E.    C.   S. Laboratories,      Inc.)

                                           NMHC      co        NOx

                Emission standards        0.39       7.0       0.7

                Pure Energy Cam           0.253      2.983     0.428

     Confirmatory testing was performed at the ARB.                  The results are shown

in Table 2.

                                         Table 2

                                 CVs—75 TEST RESULTS

                                (Haagen—Smit Laboratory}

                                          NmHq        CcQ     Nox

              Emission standards          0.39       7.0      0.7

              Pure Energy Cam test 2      0.104      1.286    0.272

      The CVS—75 emissions test results at E. C. S. Laboratories, Inc. and

confirmatory testing at the ARB indicate that HC, CO and NOx emissions of

the Pure Energy camshaft are well below the emission standards.     This

demonstrates that the installation of the Pure Energy Camshaft; P/N 12—305—

4,   for 1987 and older 267 CID (4.4L) to 350 CID (5.7) V—8 carbureted

gasoline engines will not adversely affect the exhaust emissions.

      Competition Cams has submitted all the required information and

fulfilled the requirements for an exemption.    The test results confirmed

that Competition Cams‘ Pure Energy Camshaft meets the requirements for the



                     Camshaft Installation Instructions
                 Congratulations on your purchase of a new Competition Cams camshaft. It is a highly sophisticated
           high performance part, and requires a little bit of "Tender Loving Care" during installation and break in. If
  you will take the time to read and follow these instructions you can look forward to many rewarding miles of
  driving with your Competition Cams equipped engine.
    This instruction sheet has been broken down into several categories so that it will be easier for you to use. Some of
  the topics may not apEly, but in general all of the information will be very beneficial to you during your camshaft
  installation. For step by step visual detail, we recommend that you refer to our new 35 minute instructional video,
  "The Proper Procedure to Install and Degree a Camshaft" (part #190—1). If you have any questions or problems at
  any time during your installation please don‘t hesitate to contact the toll free Cam Help tech line at 1—800—999—0853
  from 8a.m. to 8p.m. CST Monday through Friday. We are there to help you do it right the first time!

    ‘ m PO rtant & In order for your new Competition Cam‘s camshaift to be covered under any warranty,
   I\;ou must use the recommended Competition Cams lifters and the recommended Competition Cams valve springs.
    ailure to install new Competition Cams lifters and valve springs with your new cam will cause the cam lobes to
   wear excessively and will cause engine failure. If you have any questions about this application, please contact our
   technical department immediately!

   STEP 1. Prepare a clean work area, and assemble the tools needed for the camshaft installation. We suggest you
   acquire an automotive manual to help you determine which items must be removed from the motor in order to
   expose the timing chain, lifters and camshaft. A good, complete automotive manual will save you
   time and quite possibly some frustration during the installation process.
      EP 2. Once the camshaft, lifters and timinf chain are exposed, line up    the timing marks on the     I
    iming gears by rotatinfi the crankshaft (fig. A). This will position the #Fpiston at Top Dead                &
   Center. Next remove the camshaft timing chain sprocket, the timing chain, and the camshaft
   retaining plate if fiuipped. Remove all lifters, and re—install the cam sprocket to serve as a
   handle. Slowly and carefully "roll" the camshaft from the motor. Excessive force is not required.
     If the camshaft does not come out easily, stop! Look for obstructions such as fuel pump rods,
   distributor gears, etc. Do not force the camshaft. Something is holding it in the block.
   STEP 3. Once the camshaft is out, pull the bottom timing chain gear off the snout of the crankshaft. In many cases
   you will need a     gear puller to remove the crankshaft sprocket .   The bottom gear is usually an interference fit, which
   mal)ikmgakie it difficult to remove without the proper tool. Be careful not to damage the threads in the end of the
   STEP 4. Now is the time to insgect the old cam, lifters, timing components and distributor for any abnormal wear
   indications. An example would be an excessively worn distributor gear. If this gear is placed on a new camshaft it
   will destroy both the distributor and cam gear. Replace all suspect parts!

   STEP 5. Remove your new Competition Cams camshaft from its packaging. Inspect all lobes and the gear, making
   sure the camshaft was not damaged in shipment. Next compare &ae stamped numbers on the end             rmrone
                                                                                                            o    mz
   of the cam with the spec card, making sure this is the correct cam. It is a good idea at this point to
   lightly wire brush the distributor gear to remove any possible slivers or sharp edges which may
   remain after the gear has been machined. Clean the cam with mineral spirits or an equivalent sol—
   vent. Remember, during the installation process, the cleaner you keep your new components, the
   better chance you have of avoiding axu:i    of failure during the break—in period.
     Using the Competition Cams Asse        l{ ube supplied with     your cam, coat all lobes and dis—
   tributorgear. It is important to coat the lobes compfetely, yet not excessively. This same rule
   applies to the distributor gear and the fuel pump lobe (fig. B).
  oat the cam bearing journals with an SAE 30 or 40 wt. oil. Remember, we do not recommend
‘: use of synthetic oils with our cam and lifter packages during break in.
      EP 6. We recommend you install a new Competition Cams timing chain and gear set for two reasons. First, the
   old chain is likely to be stretched beyond its service limits. Second, your old timing set, as well as many new ones on
   the market, may be machined to retard the cam timing. Either of these conditions will detract from the performance
   your camshaft was designed to deliver.

   Temporarily install the new cam sprocket on the camshaft. The sprocket will again serve
 as a handle to help "roll" the cam in to its bearings. Carefully slide the camshaft into the
 motor, oiling thebearing journals as it slides into the block (fig. C). Excessive force is not
 necessary to install the cam. Take your time. You do not want to scar the camshaft or the
        bearings. Be sure you do not wipe away any of the assembly lube as you install the
        into the block.

 STEP 7. Install the new crankshaft sprocket on the snoutof the crankshaft (fig. D). Be sure
 that the sprocket has "bottomed out" on the crankshaft. If the bottom gear has not been
 properly installed, chain misalignment will occur. This could cause severe damage!        ,
   If your engine was equipped with a camshaft retaining plate, it should beinstalled at this
 time. Some engines have a spacer between the camshaft    and the upper timing gear, and
 some of the replacement gears are made with this spacer mcomed into the gear. To
 insure that you have the correct combination of parts, simply c     the end play of the cam.
 It should be within .004" to .008" when a retainingJ)la(e is used. When a retaining plate is
 not incorporated in the engine, the taper on the hydraulic or solid lifter lobes will hold the
 camshaft in position. When a roller cam is used, either a retaining plate or a camshaft thrust
 button must be used.

   It isn‘t absolutely necessary to degree the cam for the motorto run efficienfl{. We grind all of our High Energy and
 Magnum cams 4° advanced to make up for all machining tolerances. This will position the cam for the best street
 perfi;\rmnce. However, to assure maximum performance we recommend you degree your new Competition Cams
 camshaft. The purpose of degreeing a cam is to correct the errors and tolerances in the machining processes of the
 engine that effect camshaft timinfg. f you do decide to degree your new cam, we suggest the intake centerline
 method. It‘s simple, quick and efficient!
   For instructions, see "How To Degree Your Cam" on pages 7—8 of this brochure.
 STEP 8 Check the timing mark alignment in your engine manual. Rotate the crankshaft and
 camshaft to its proper position. Our small block Chevy has a "dot over dot" alignment as
 shown {fig. E). Remove the camshaft sprocket and install the new Competition Cams chain.
                   gasg Bolt the cam sprocket to the cam making sure the sprocket is pulled
                               up flush onto the cam (fig. F). Once again make sure the timing
                               marks are positioned properly and according to your manual.
                                Refer to your manual for the proper torque specification before
                             @ tightening the camshaft bolt or      bolts. We also suggest that loctite be
                               applied to the threads of the camshaft bolts to assure the bolts remain
                               torqued to the proper specification. This process is very important! Imfiroperly torqued
                               camshaft bolts can loosen up and cause severe engine damage. A camshaft bolt locking plate
                               is recommended for Chevrolet 262— and%96-454cu. in. engines. Ask for Competition
                               Cams part #4605.
                               STEP 9. Remove your new Competition Cams lifters from the packaging and clean the lifters
                               thoroughly in mineral spirits or equivalent solvent. Remember, in order to protect your cam—
                               shaft warranty, new lifters must be installed. We recommend new Competition Cams lifters
                               be used to assure maximum performance and reliablility. Coat the bottom ofall lifters with
                               the Competition Cams lube supplied with your cam and use SAE 30 wt. oil on the sides
                               (fig. G).     Install thelifters, making sure they fit well and rotate freely. Any excess clearance or
                               tight lifters will cause damage to the camsga!t and lead to engine failure.

 STEP 10. Next, we recommend you install Competition Cams Magnum Rocker Arms and
 Push Rods. They will insure compatible mating surfaces and long life, Additionally, be—
 cause of the increased stiffness, accuracy of ratios and roller tip, the Magnum Roller Rockers
 can give you up to an extra 15 to 30 HP over stock rocker arms. Both the Magnum Rockers
 and Competition Cams Push Rods are conveniently packaged for you in the RP—KIT (fig. H).
   Clean all push rods thoroughly because most engines oil through the center of them.     the
 original push rods are being used, be especially sure they are clean inside and out. Apply a
moony          °       rig     Small amount of Competition Cams lube or equivalentlube on each
                   %           end of the push rod and install into the motor (fig. D).
                                 Clean all rocker arms thoroughly. If the original rocker arms are used, examine each one for
                               excessive wear and replace any that are questionable. A;E:ly a small amount of Competition
                               Cams lube on all contact areas of the rocker arm. With a clean rag or towel wipe the tips of
                               the valves clean and apply Competition Cams lube on the tip of each valve where the rocker
                               arm will come in contact with it. Also be sure to check the valve tips for excessive wear.

 STEP 11. Install rocker arms onto motor (fig. J). Do not tighten the adjusting nut down before
  ou go through the proper       sequence. On engines with shaft mounted adjustable rocker arms,
 {ack off all adjusters completely before installing the assembly. Make sure the push rod is in
  he lifter and the rocker arm seat when making valve adjustments.                            —
                   ¥Y—3     For hydraulic lifter camshaft adjustment, turn the engine in the
                        § normal direction of rotation. When the exhaust valve moves to maxi—      B
                          mum lift, adjust the intake valve to zero lash with no preload. Turn the
                          adjusting nut an additional 1/2 turn more. Rotate the motor over again
                          until the intake valve reaches maximum lift and is almost all the way
                          back down. Set the exhaust valve to zero lash plus a 1/2 turn. Adjust
                          the valves on each cylinder in this manner unu}l’ all valves are adjusted (fig. K).
                            If your engine has non—adjustable rocker arms, a lifter preload of .020 to .040 must be main—
     —          oc         See "Lifter Preload Made Easy" for proper preload instructions.
 For mechanical lifter camshafts, follow the same adjustment procedure. Instead oflifter preload, use the prescribed
valve lash clearance found on the cam specification card.
STEP 12. It is very important to "fire" the engine as quickly as possible. The only lubrication that the camshaft re—
ceives is from oil stung off the crankshaft, First, change theoil and filter using an SE, SF grade or racing oil for initial
break—in. Fill the new oil filter with oil before installing, This allows the motor to achieve oil pressure immediately.
  Timing the motor properly the first time will be necessary for the motor to start quickly. The following procedure
is simple and effective.
  Rotate the crankshaft in normal crankshaft rotation until the number one cylinder is coming up on the compression
stroke. Align the timing mark on the balancer/dampner to the recommended factory initial tming setting, being
sure that both valves on the #1 cylinder are closed. Install the distributor with the rotor pointing to the #1 plug wire
on the cap. The motor should fire up as soon as it receives fuel.
STEP 13. Important! As soon as the motor fires, bring the engine RPM to 1500 to 2000 RPM during the first 30 min—
utes of operation. Slower engine speeds may not supply the camshaft with an adequate amount o% oil for the break—
in period.                                                .
   hange RPM periodically to direct oil splash to differentareas of the camshaft. After the 30 minute break—in time,
change the oil and filter again to be sure all contaminants and break—in lube are removed from the motor.
 If you do not understand any       part or all of these instructions, please contact one of our technical consultants at
1‘999—0853. We will be glad to help you with any problem you may have.

Lifter Pre—load Made Easy
 When installin% a hydraulic cam, new hydraulic lifters, or replacing rocker arms, it is necessary to establish the
proper lifter pre—load. Insufficient lifter pre—load will cause excessive valve train noise. Excessive lifter pre—load will
cause the motor to idle rough or have low manifold vacuum and can lead to severe engine damage. It is critical to
engine efficiency and to the service life of the valve train (camshaft, lifters, push rods, valve springs etc.) for the
lifters to have the proper amountof lifter pre—load.
 On any hydraulic lifter camshaft the ideal lifter pre—load should be .030". A variance of + or — .010"is acceptable.
Two methods are used in settinE lifter preload. One is for adjustable rocker systems such as a small block Chevy,
and the other is for non—adjustable systems such as the small block Chrysler.

Adjustable Rocker Arms
 Install the push rods into the motor. Install the rocker arms, balls and nuts on the rocker
studs. Be sure the push rods are seated properly into the lifter and the rocker arm seats.
 Turn the engine over by hand in the direction of rotation until the exhaust push rod just
   ins to move upward to open the vaive. You are now ready to adjust the mmtake rocker of the
         f \“? same            cylinder (fig. L).
                        Carefully tighten the nut on the intake rocker arm while spinning the
                       push rod wi zgur fingertips. You will feel a slight resistance in g\e push
                     § rod when you        have taken up all of the clearance. This is refered to as
                       "zero lash". Now turn the adjusting nut 1/2 turn more. Generally 1/2 turn on the adjusting
                       nut will provide the suggested .030" pre—load.
                         Once again, turn the engine in its direction of running rotation until the intake push rod
                     § comes all the way up and almost all the way back down. Now set the exhaust rocker to "zero
                       lash" and add 1/2 turn (fig. M). You now have set the pre—load on one cylinder. Repeat these
                       same steps to set the pre—load on each cylinder.                          j

    Non—adjustable Rocker Arms
     In situations where you are dealing with non—adjustable rocker arms, a different procedure must be followed. After
    applying lube, install the pushrods and torque all rocker arm bolts down in the proper sequence and torque specifi—
         ion.   Rotate the motor by hand in the normal direction of motor rotation until both the exhaust and intake valves
Qe opened and closed completely. Allow a couple of minutes for the lifter to bleed down.                           .
     sing the vailve cover gasket surface on the head as a reference point, place a mark on the pushrod. Tt is advisable
 to use a pencil or scribe to mark the push rod. The smaller and more defined the mark, the more accurate the meas—
    urement. Be sure the reference point you choose for the first mark is easily accessible and easy to duplicate. You will
    be marking the push rod twice. It must be from the same reference point and angle for the measurement to be
      Loosen the rocker or rocker shaft bolts. Leave the rockers on the head so that they will support the push rods. Be
    sure the push rods are standing free in the lifters, and do not have any pre—load. Using the same reference point,
    place a second mark on the push rod. Make sure the angle and reference             pointare the same as the first mark.
         You now have two marks on the push rod; one with the assembly bolted         into place as the motor will run, and the
    second mark with the lifter unloaded. The distance between these two points will represent the amount oflifter pre—
    load your motor has.
         If you find that the pre—load is not within .020" to .040" range, adjustment will be necessary, The simplest way to
    accomplish this is by using different lengthcFush rods. These push rods are available for most motors with non—
    adjustable rockers. When measuring to find the correct length needed, be sure to include the .030" pre—load that the
    lifter requires.
         If ofi? engine has      pedestal style (bolt mounted) rockers, you can use shims under the      pedestal to lessen th?fpre-
    load. This method also works with shaft mounted rocker systems. Longer pushrods will be needed for insufficient
    P In most cases you will only need to check one intake and one exhaust i:lSh rod. However, if your valve stem
    heights are not equal you will need to check pre—load on each vaive. If this procedure is not followed, it will almost
    certainly result in a poor running engine and ultimately engine failure.

     Valve Springs
       The number one factor in premature failure of a new camshaft is the valve spring. Either incorrect pressure or
     incorrect spring application will lead to a worn out cam. For this reason it is highly recommended that the corre—
     sponding part number Competition Cams spring be used in any cam change.                                   —
.        ost aftermarket cams have much higher than stock lift. Therefore the stock vaive springs
          "coil bind" or "stack" before the cam reaches its full lift. This condition will cause the
          to fail immediately. You should always use the recommended part number spring with
     a new cam, and check to be sure there is no coil bind. With the valve at full lift, check the
     clearance between the coils. You need to maintain a minimum of .060" between the coils at
     this point (fig. NJ.
       Excessive spring pressures will also lead to early failure. These pressures can be the result
     of incorrect springs, short valves, improper retainers, or many other factors unrelated to the
     cam orthe valve spring. The only way to ensure the correct pressure is to actually check the
     installed height and pressure. Refer to the instructions in the valve spring box or contact a
     local machine shop for help.
          Coil bind will not usuall%be a problem when High Energy Camshafts are used. However, the big block Chevy is
     an exception to this rule.      When installing any non stock cam it‘s recommended to check for coilbind, butit is im—
     perative that coil bind be checked on the higher lift and Magnum Series of Camshafts. With the 292H or 305H Mag—
     num Cams the valve springs must be replaced. Stock valve springs will not have sufficient travel for cams that incor—
     porate that much lift.                                                                         >

     Rocker Arm Clearance
         Rocker arm clearance must be checked at several‘flaees‘ It is very common with higher lift
     cams to have the rocker arm contact the rocker stud when the valve is at full open position. Be
     certain to check this, as lack of proper clearance will cause broken studs, broken pushrods, or a
     worn out camshaft.
       The clearance between the rocker arm and the retainer must also be checked. This problem
     will be more pronounced when the valve is closed. The retainer is likely to contact the under—
     side of theCr)ocker arm right in the center. Be sure to maintain at least .030" clearance at this
     point (fig.    O}.
         When assembling the head, check the retainer to valve seal clearance. Sometimes when you
     i       1 a high lift cam and a differentseal, this distance becomnes too small. This will bind the
              train and result in camshaft failure. If the clearance does not measure the total valve lift
             ‘060" the heads should go to a machine shop and the guides shortened.
           ushrod clearance must also be checked, especially when using a higher ratio rocker arm.
     The pushrod seat in the rocker is moved toward the stud in this case, so it must be checked at
     several different lift points.

    Piston To Valve Clearance
       Anytime a higher than stock lift camshatft is installed it is important to check piston to valve clearance. The High
       ergy   Series and smaller Magnum Cams, such as the 270H, 280H, 270$ or 268AR camshaifts, should not have this
    problem. However, the 292H, 294S, 280AR and larger camshafts may have an interference problem.
      Competition Cams strongly urges you to check the piston to valve clearance on the larger street cams, and on all .
    race cams. We recommend at least .100" clearance on the intake valve and at least .125" for exhaust vaives. If alumi—
    num rods are used, add a minimum of .030" to the suggested clearance figures. Aluminum rods will stretch and
    expand more than a steel rod.
      The easiest and possibly most accurate way to check piston to valve clearance is to place strips of modeling clay on
     top of one of the pistons, then rotate the engine over by hand with the head bolted in place and all of the vaive train
     with vaives adjusted. The clay will be compressed to             the exact clearance. You can remove the head and measure the
     thickness of the clay. If the enLEine meets resistance in turning, stop! You probably have no clearance.
       A decision must be made either to flycutthe pistons, which will involve completely disassembling the motor, or to
     exchange the cam for a profile that will fit into your motor. Do not try to operate the motor with less than .100"
     clearance on the intake and .125" on the exhaust. Severe damage will occur!
     STEP 1. With the camshaft installed, remove the cylinder head from the block. Clean the combustion chamber ans
     the top of the piston and valve reliefs. The cleaner the piston, the better the clay will stick to it.           zp        s

     STEP 2. Apply a strip of modeling clay 3/8" to 1/2" wide and approximately 1/4" thick to the
     pistons. The clay strips should be placed perpendicular (across) the intake and exhaust valve
     reliefs (fig. P). Applying a small amount of oil to the clay will preventit from sticking to the
     valves as they press into the clay.

     STEP 3. Reinstall the cylinder head with the gasket that is going to be used. It will not be neces—
     sary to re—torque the head yet. All head gasket manufacturers cantell you what the compressed
     thickness of their fiasket will be. Measure the gasket before you install it permanently, and add
> ‘he difference of the gasket thickness to your piston to vaive clearance.    This will be within .001" or .002" of the exact
     Install a sufficient number of head bolts to secure head in place while you are rotating the motor. Install the push
     rods, lifters and rocker arms on the cylinder you have prepared for the clearance check.
     STEP 4. Ad{ust the rocker arms to their suggested clearance. If the camshaft you are checking
     uses hydraulic lifters, you must use solid lifters in their place. Hydraulic lifters bleed down, and
     would &rovide a false measurement. Once the hydraulic lifters are replaced with solid lifters,
     adjust    the lash to "zero". Be sure notto preload the valve spring (fig. Q).

     STEP 5. Now turn the motor over by hand in the normal direction of rotation. Be sure to rotate
     the motor over 2 times. This will be one complete revolution of the cam and assure you of an
     accurate reading on both the intake and exhaust. Remove the cylinder head from the block. Be
     sure to do this gently, so the clay is not disturbed. It may be stuck to the valves or combustion
     chamber, so be careful.

     STEP 6. With a razor or sharp knife, slice the clay cleanly, lengthwise through the depression
     and peel half of it off the piston (fig. R). The clay‘s thickness in the thinnest area will represent
     the minimum piston to valve clearance.

                         _|     STEP 7. To accurately check the thickness, use a set of dial calill>ers (fig. S).
                              i The clay can also be measured close enough with a thin steel rule.

                           g NOTE: Be sure to check piston to valve clearance after the cam has been degreed in. The posi—
                                tioning of the cam in the engine will greatly affect the piston to valve clearance.

                                                                                                                       C     petition
               FMS "VaiveTrains Engineered                                                                            4 1—800—999—0853
                              for the Way You Drive!                                                                        soure es
                                                                                                                           dn se Esn

   The purpose of degreeing a camshaft is to insure thatit is phased correctly with the crankshaft, Some factors that
       cause improper positioning are:
       m or crank gear marked incorrectly .
    ‘ Incorrectly machined cam or crank gear keyways
  3. Misindexed cam keyway or dowel pin
  4. Improper machining of camshaft or crankshaft
  5. Accumulation of machining tolerances
  The important thing to remember is that camshaift position or phasing to the engine is extremely important for the
  engine to operate at maximum efficiency.
       re are several pieces of equipment needed to properly "degree" in a camshaft. They are sold at Comp Cams
  and are as follows:
  1. A degree wheel
  2. A rigid pointer that can be attached to the block
  3. A dial indicator to accurately measure cam lift. Note: Refer to ?'our spec card for maximum lift, and check your
  dial indicator to be sure it has sufficient range to measure the full cam lift.
  4. Either a magnetic or attachable base with which to affix the dial indicator
  5. A Top Dead Center stop                               —
  6. A solid lifter to fit your motor. Motors that have non—adjustable rocker arms will also require an adjustable push
  rod that accomodates that motor.                       —                               '                e             ,
  7. A means to attach the degree wheel to the crankshaft                                             $
  A "Cam Degreeing Kit" is available, Comp Cams Part #4796 (fig A}.

   There are several accepted ways to degree a camshaft,. At Competition Cams we feel the
 Intake Centerline Method is the easiest and most accurate. This method of cam degreeing is
 very practical and indifferent to design characteristics. It simp)&nvolves positioning the
 center, or point of maximum lift, of the #1 intake lobe with top Dead Center of the #1 piston.
 The Intake Centerline Method still       requires accuracy to be correct, butit is somewhat more forgiving. Once you have
 degreed a camshaft using this method, you will be surprised at its ease. We also recommend positioning the dial
 indicator on the #1 intake retainer because lift measurements will include any deflection that may occurin the push
‘gnd rocker arm. This makes the degreeing process as accurate as possible in relation to what actually goes on
       e the engine.

  STEP 1. The camshaft and timing set have been installed. Make sure that the timing marks on both the cam gear
  31'\? cra;\\k geaxi(:re aligned properly per the cam installation instructions. Use chalk or similar marker to better
   efine the marks.
  STEP 2. We have our cam card, and it suggests we install the cam on a 106° intake centerline. Install all the rocker
  arms and push rods in the motor as normal. On #1 intake lobe, install the solid lifter in place of the hydraulic lifter.
  If a solid lifter orroller cam is being checked, use that respective lifter. Adjust the #1 intake lash to exactly zero. Do
  not preload the lifter. Next, adjust the #1 exhaust lash to zerq. You should be ableto turn both push rods with your
  fingers easily.                                                                                               s

  STEP 3. Attach the pointer to the block. Many people will make a pointer out of some sort
  of rigid, yet manageable wire. Stiff coat hanger wire works well (fig. B).
  STEP 4. Attach the degree wheel to the balancer and install the assembly on the crankshaft.
  There are several ways to attach the degree wheel to the crankshaft. In our example, the
  degree wheel is mounted to the balancer. The crank may be rotated from either      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, thus more accuracy.
  NEVER use the starter to turn the engine while degreeing the cam.
  STEP 5. Before installing the piston stop, rotate the crankshaft to get the #1 piston in ap—
  proximate T.D.C.position with both the intake and exhaust valves closed.        This can be a
  rough guess, butit can save you from making a mistake later. Adjust your pointer to zero or
  T.D.C. on the degree wheel.                                                                >
      [P 6. Turn the crankshaft opposite the motor rotation approximately 15—20 degrees. This
       Aower the piston enough to allow the T.D.C. stop to be installed in the spark plug hole.
     ‘ew in the piston stop untilit touches the piston(fig. C). Continue to turn the engine in
  the same direction until the piston comes back up and touches the piston stop.

                          Mark the dglgree wheel with a S‘en or pencil on the degree the pointer is
                          on(fig. D). Turn the engine in the other direction, same as motor rotation,
                          until the piston comes    back up and touches the piston stop. Make a mark
                          on the degree the pointer is on (fig. E).

                          STEP 7. Count the number of de%rees between the two marks and divide them in half. For ex—
                          ample, lets say your marks are 40° apart from each other. Forty divided by 2 is 20, so 20° from
                          either mark is T.D.C. Move the pointer to align      it 20° from either mark, without moving the en—
                          gine or degree wheel (fig. F). Now you have found Top Dead Center. Re—            |=      7      —
                          move your piston stop, and you are ready to properly degree your cam.

                          STEP 8. Attach the dial indicator to the dial indicator mount. Position the
                          dial indicator mount so the tip of the dial indicator will contact the re—  f
                          tainer of the #1 intake valve (fig. G). It is important that the indicator
                          plunger be parallel to the valvestem. Any variance in the angle of the in—
    dicator will introduce geometric errors into the lift readings.

    STEP 9. Rotate the engine in the normal direction of crankshaft rotation until ou reach maxi—
   mum lift, The dial indicator will change direction at the point of maximum lift. At this point,
   set the dial to zero (fig. H).
   STEP 10. Back the engine up (opposite normal rotation) until the indicator reads .100". Turn
   the engine back in the normal direction of rotation until the dial indicator reads .050" before
   maximum lift. Record the degree wheel reading.

   STEP 11. Continue to rotate the motor over in its normal direction of rotation until the indica—
   tor goes past zero to .050" on the closing side of maximum lift. Again record the degree wheel
‘TEP 12. Add the two numbers together and divide by two. That number will be the location of maximum lift of
     e intake lobe in relation to the crank and piston. This is the intake centerline. For example: The first degree wheel
     ading was 96°. The second reading was 116°, These two numbers (96 + 116) added together will be 212. That
   number (212) divided by 2 will equal 106. Your actual intakecenterline is 106°. Refering back to your cam spec card,
   we see that the recommended intake centerline for your camshaft is 106°. Everything is where it should be.
     In the event that your camshaft did not degree in as per manufacturers specs, it will be necessary to either advance
   (move the cam ahead) or retard (move the cam back) the cam to meet the suggested intake centerline. Depending on
   the motor application, there are several different suggested methods for advancing or retarding the camshaft,
     One common method is by use of a crank gear with multiple keyways, each one being at a slightly different
   relationship to the gear teeth. A second methodis to use offset bushings thatfit on the cam pin anc(in the cam gear.
   The offset will advance or retard the cam depending on how the bushing is placed on the cam pin. Another method
   is by offset keés that fit into the crank gear keyway. A more elaborate and expensive system is with an adjustable
   tirm]r_\g gear. Contact Competition Cams or your local Competition Cams dea?eer for the method best suited to your
     Note: When degreeing in a cam, remember to look at the degree wheel as a full 360°, no matter how the degree
   wheel you‘re using is marked. Many degree wheels are marked in 90° or 180° increments. On wheels that are
   marked in 90° increments keep in mind that you must continue to count the number of degrees on past 90°. Be sure
   all readings are taken from Top Dead Center.                                                —
     Keep in mind that to advance the cam, you must lower the intake centerline. For example, if our cam has a lobe
   separation of 110°, the cam is "straight up" when the intake centerline is 110°, Moving the centerline to 106° ad—
   vances the cam 4°. If we change the centerline to 112°, this would be 2° retarded.

    We at Competition Cams hope that these instructions have been helpful in making your
   camshaft installation a successful and pleasant experience. Conc\ipetition Cams has also pro—
   duced a video tape entitled "The Proper Procedure to Install and Degree a Camshaft".            This
   video covers all of the points discussed here and illustrates many other helpful tips to achieve
   the maximum performance from your engine. If you wish to order this video, or if you have
   any other questions concerning your cam change, please contact our Cam Help technical line at
   1—800—999—0853. They are there to help you, and are available from 8:00a.m. to 8:00p.m. CST
      onday through Friday.

                                                                s ° VaiveTrains Engineered
                                                                      for the Way You Drive!

Document Created: 2005-09-01 12:40:22
Document Modified: 2005-09-01 12:40:22

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