Approval Details

Valid E.O.

Validity

This Executive Order approved the specified parts on on April 1, 1992.
As of Monday, December 30th, 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

| Previous E.O. D-249 | Next E.O. D-250-1 | Next E.O. D-251