Approval Details

Valid E.O.

Validity

This Executive Order approved the specified parts on on April 1, 1992.
As of Friday, December 6th, 2024 this Executive Order has not been overturned or superceeded.

Approved Parts

Models
1992 and older General Motors vehicles sold in california equiped with 262 CID (4.2L) ti 400 CID (6.6L) V-8 gasoline engines

This Executive Order may be listed as:
  • C.A.R.B.E.O. D-250
  • Executive Order 250 / D250
  • ARB # D-250
  • Executive Order No: D-250
  • C.A.R.B. No. D-250
  • Resolution D-250
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-250 PDF

D-250 Document:


CARB_D-250

                                                     (Page 1 of 2)

                               State of California
                               AIR RESOURCES BOARD

                             EXECUTIVE ORDER D—250
                   Relating to Exemptions Under Section 27156
                              of the Vehicle Code

                            AIR FLOW RESEARCH COMPANY
                               ALUMINUM STREET HEAD

Pursuant to the authority vested in the Air Resources Bcard by Section 27156
of the Vehicle Code; sand

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

IT IS ORDERED AND RESOLVED:  That the installation of the Aluminum Street
Head manufactured by Air Flow Research Company (Air Flow Research) of 10490
Ilex Ave.,   Pacoima,   California 91331—3137 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 1992 and older General Motors vehicles sold in California equipped
with 262 CID (4.2L) to 400 CID (6.6L) V—8 gasoline engines.

This Executive Order is valid provided that installatior instructions for
this Aluminum Street Head will not recommend tuning the vehicle to
specifications different from those submitted by Air Flow Research.

Changes made to the design or operating conditions of the Aluminum Street
Head,   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 cylinder head using any identification other than that
shown in this Executive Order or marketing of this cylinder head 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 cylinder head 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 cylinder head may have on any warranty either expressed or
implied by the vehicle manufacturer.

THIS EXECUTIVE ORDER DOES NOT CONSTITUTE A CERTIFICATIO®, ACCREDITATION,
APPROVAL, OR ANY OTHER TYPE OF ENDORSEMENT BY THE AIR RESOURCES BOARD OF
CLAIMS OF THE APPLICANT CONCERNING ANTI—POLLUTION BENEFITS OR ANY ALLEGED
BENEFITS OF AIR FLOW RESEARCH COMPANY‘S ALUMINUM STREET HEAD.

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.


AIR FLOW RESEARCH COMPANY                         EXECUTIVE ORDER D—250
ALUMINUM STREET HEAD                              (Page 2 of 2)

Violation 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   z   day of April, 1992.
                                   )




                       Assis¥ant Division Chief
                       Mobile Source Division


                    State of California
                    AIR RESOURCES BOARD




EVALUATION OF AIR FLOW RESEARCH COMPANY ALUMINUM STREET HEAD
      FOR EXEMPTION FROM THE PROHIBITIONS OF VEHICLE CODE
 SECTION 27156 IN ACCORDANCE WITH SECTION 2222, TITLE 13, OF
              THE CALIFORNIA CODE OF REGULATIONS




                         April 1992


                            State of California
                            AIR RESOURCES BOARD




        EVALUATION OF AIR FLOW RESEARCH COMPANY ALUMINUM STREET HEAD
             FOR EXEMPTION FROM THE PROHIBITIONS OF VEHICLE CODE
        SECTION 27156 IN ACCORDANCE WITH SECTION 2222, TITLE 13, OF
                     THE CALIFORNIA CODE OF REGULATIONS




                                     by
                          Mobile Source Division
                            State of California
                            Air Resources Board
                            9528 Telstar Avenue
                          El Monte, CA 91731—2990




(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.)


                                  SUMMARY



     Air Flow Research Company (Air Flow Research) has applied for an

exemption from the prohibitions of Vehicle Code Section 27156 for their

Aluminum Street Head for installation on 1992 and older General Motors (GM)

vehicles equipped with 262 CID (4.2L) to 400 CID (6.6L) V—8 gasoline engine.

Air Flow Research has submitted a completed application and all the required

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

Automobile Club of Southern California which demonstrated that the Aluminum

Street Head does not have any adverse effect on the exhaust emissions of the

affected vehicles.

     Based on submitted information and results of emission tests performed

at the Automobile Club of Southern California, the staff concludes that the

installation of Air Flow Research‘s Aluminum Street Head will not adversely

affect exhaust emissions on the specified vehicles.

     The staff recommends Air Flow Research Company be granted an exemption

as requested and that Executive Order D—250 be issued.


                             TABLE OF CONTENTS



                                                    Page Number


SUMMARY

CONTENTS                                                 i1

I.         INTRODUCTION




                                                         ode
II.        CONCLUSION




                                                         e
III.       RECOMMENDATION




                                                         e
IV.        ALUMINUM STREET HEAD DESCRIPTION




                                                         ob
           DISCUSSION OF THE ALUMINUM STREET HEAD




                                                         moobr
           APPENDIX — Installation instructions




                                     ii


           EVALUATION OF AIR FLOW RESEARCH‘S ALUMINUM STREET HEAD
 EXEMPTION FROM THE PROHIBITIONS OF VEHICLE CODE SECTION 27156 IN ACCORDANCE
     WITH SECTION 2222, TITLE 13, OF THE CALIFORNIA CODE OF REGULATIONS



I.    INTRODUCTION

      Air Flow Research Company (Air Flow Research) of 10490 Ilex Ave.,

Pacoima, California 91331—3137, has applied for an exemption from the

prohibitions of Vehicle Code Section 27156 for their Aluminum Street Head

for installation on 1992 and older General Motors (GM) vehicles equipped

with 262 CID to 400 CID V—8 gasoline engines.    Air Flow Research has

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

as exhaust emissions test data performed at the Automobile Club of Southern

California which demonstrated that the Aluminum Street Head does not have

any adverse effect on the exhaust emissions of the affected vehicles.

II.    CONCLUSIONS

      Based on submitted information and the results of the emission tests

performed at Automobile Club of Southern California,   the staff concludes

that Air Flow Research‘s Aluminum Street Head will not adversely affect

exhaust emissions from vehicles for which the exemption is requested.

III. RECOMMENDATION

      The staff recommends that Air Flow Research Company be granted an

exemption as requested and that Executive Order D—250 be issued.

IV.   ALUMINUM STREET HEAD DESCRIPTION

      The Aluminum Street Heads are specifically designed for installation on

1992 and older GM vehicles powered by 262 CID (4.2L) to 400 CID (6.6L) v—8

gasoline engines.    The Aluminum Street Head operates in conjunction with the

original equipment manufacturer‘s (OEM) emission control systems already

certified with the stock engine.   The purpose of using the modified Aluminum

Street Head is to increase the overall engine performance which is

accomplished through the use of the finest materials

                                      —1—


available along with labor intensive machining.          The intake and exhaust

ports are machined to match the gasket and manifold surfaces, thus

eliminating reversion at those junctures.         The interior surfaces of the

ports have been machined in the critical areas to reduce backpressure and

maintain laminar flow.       The valve seats are machined to provide optimum

sealing and increased flow.       The combustion chambers are polished to

eliminate hot spots which could cause detonation or pre—ignition.

     The following are the Aluminum Street Head specifications:

           1.     Head Casting ——————— Aluminum

           2.     Valves <————~—«———~—— 2.02" Diameter Intake

                            ————————————— 1.6" Diameter Exhaust

v.   DISCUSSION OF THE ALUMINUM STREET HEAD

     Air Flow Research submitted emission testing conducted at the

Automobile Club of Southern California.          A 1990 California—certified

Chevrolet full size truck powered by a 350 CID (5.7 liter) engine was used

as the test vehicle for the Aluminum Street Head.          The dynamometer inertia

weight and loading used during the testing were 4500 lbs. and 9.8 hp,

respectively.

     Emission testing consisted of one cold—start CVS—75 Federal Test

Procedure in the modified configuration, and evaluated against the vehicle‘s

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


                                       Table 1

                                 CVs—75 TEST RESULTS
                       {Automobile Club of Southern California)

                Test                     Exhaust Emissions (gm/mi)

                Mode                     HC       co     Nox
                Standards               0.50      9.00   1.00
                Aluminum Street Head    0.31      3.57   0.55

                Difference             —0.19     —5.43 —0.45


     The CVS—75 emissions test results at Automobile Club of Southern

California indicate that HC,   CO and NOx emissions of the vehicle, with the

Aluminum Street Head installed,    are below the emission standards set for

that engine family.

     The Air Resources Board did not conduct confirmatory tests to validate

the emission test results submitted by Air Flow Research.     The Aluminum

Street Head is functionally identical to the original equipment

manufacturer‘s (OEM) cylinder head except for its valve sizes and casting

material.   A typical GM cylinder head may have intake valves ranging from

1.72 to 1.94 inches and exhaust valves ranging from 1.5 to 1.6 inches, with

cast iron construction.   Air Flow Research consolidated these variations by

designing their cylinder head to be at the top end of the OEM scale, 2.02

inches on intake and 1.6 inches on exhaust with the cylinder head

constructed out of aluminum.     The exhaust valve diameter is still within

acceptable OEM range while the intake valve diameter translates to a 5

percent increase over OEM.     The test results confirmed that the minimal

increase in the intake valve diameter does not cause any significant

increase in emissions.

     Air Flow Research has submitted all the required information and

fulfilled the requirements for an exemption.


APPENDIX


                        AIR FLOW RESEARCH HEADS. INC.
                        (818)A90—0616 FAX (818)8§0—0480

                            GENERAL LNFORMATION
                        SMALL BLDCK ALUMINUNM RHEADS


ATTN: PLEASE READ THROUGR ALL            INSTRUCTIONS BEFORE ATTEMPTING
CYLINDER HEAD INSTALLATION.

AIR FLOW RESEARCH STREET HEADS ARE D{RECT REPLACEMENT CYLINDER
HEADS FOR ALL SMALL BLOCK CHEVROLET ENGINES wWITH LT—i HEADS.
SEE ATTACHED LISTING FOR SPECIFIC MODELS AND YEARS.


HEAD GASKETS:     Fel   Pro    No.    1010 for ali    aiuminum heads up to
4.155" bore.              1

INTAKE GASKETS:   Fel Pro No. 1256 gaskets shoulid be usea on ail
i90cc street heads. Fel Pro No. 1205 gaskets should be used on
the 19500 street heads.    These gaskets are designed to seat
properly,   instalied    ary    ino    silicone}>;   nowever,       a    smail   amount      of
gasket cinch at each end of the gasket, between the heand
and gasket, is heipful in requcing movement during assemoiy.

EXHAUST GASKETS: Fel Pro No. 1404 exhaust                  gasket       shouid   be   used
on all street heads (190cc, i950c).

HEAD BQLTS & WASHERS: Quality relie? ground boits or studs are
preferabie.  Large i3274" or larger)  neag washers are necessary
to prevent the bolits from indenting into the aiuminum nead.
Washer size shouid be same size of tne ooir or nut you are using.
insutficient diameter and/or bevei faced wasners wiil sink into
the neac and cause a ioss of nead paolt torque.

HEAD BOLT TORQUE:  fHeads should be torqued to 65 to 70 ibs. This
should be done in the proper Genersal hMotors sequence in i0
ft./lb. increments beginning at 40 ft./ibs.     All head boits
should be retorqued after the first run in ana cool down.
Failure to retorque all boits may cause andue stress and
cracking.

ROCKER STUD LOCATION: The Air Flow Research head has a standard
G.M. rocker arm stud locations.  The i9%0cc and 195cc neads use
standard pushrod location.

STUD GIRDLE:— The AFR 190cc and 1950c heads use                     standard G.HM.
  offset stud girdle is necessary for tne 220c0
stud girdies.

PUSHROD — GUIDEPLATE INSTALLATION: ATTN: USE AFR GUIDEPLATES
SUPPLIED WITH EACH SET OF HEAbDS ONLY. Pusnrod guidepiates are
furnished with ali AFR aluminum heads at no extra cost. Studs
should be torqued to 50 ft./los.             The i§G%Gec and i§5cc satreet neags
require the    long   siot of    the    guidepiate    to    straddle       the exnaust
pushrod.                                    '


v‘   x IMPORTANT — 5/16 THICKWALL ChHROME MOLY HEAT TKERATEL PUSHRKODS
     SHOULD BE USED TD AVOID GALLING OF PUSHRODS.

     ROCKER ARMS:  The Air Flow kesearch i190cc and i95ce Street
     aluminum heads are designed to use standard GM or O£ rocker
     arms.

     VALVE SI1ZES:        Both intake and exhaust            vaive seats are heat        treated
     and   will     run   on   unieaaed     fuel.


     SPARK    PLUGS:       Champion    "N"    series,   AC    "XL"   series    or   Autolite
     "AG" series spark plugs are recommended. (14MM x 3/4>
     For street use, AFR recommends AC FR3LS spark piugs or‘its
     equivaient.   FPlug selection is of course dictated
     by rpm ievel, application and fueil used.   For those with header
     clearance probiems, we suggest AC FRKGLS spar« plugs with i1/4" snorter
     top.                  ‘                      '

     400 BLOCK:—  We suggest that you or Air Filow Research                         drill steam
     holes in the heads to keep the biock distortion to a                           minimum.
     Use Feil Pro Head Gasket #1034 for 400 blocks.   These                         will fit
     bores up to 4.190..  Eel Pro #5364 nas steam noles in                          gasket out
     shouid    be   considered for          street   appiications      oniy.

     P1STON TO VALVE CLEARANCE:               Be sure   to   cneck your      compression
     ratio    and   piston     to   vaive   ctearance    berore      finai   assembly   Oof
     tnese    heads on your         engine.



Document Created: 2005-09-01 12:43:32
Document Modified: 2005-09-01 12:43:32

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