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4. POTENTIAL OF SPARK-IGNITION INTERNAL-COMBUSTION ENGINES FOR MEETING STANDARDS IN USE 4.1 Introduction . Section 3 presented an evaluation of the feasibility of spark- ignition internal-combustion engines passing the certification test for 1975 and 1976. This section assesses the feasibility of such en- gines continuing to meet the standards in customers' hands. In this assessment, the first question to be answered is the adequacy of the certification test to evaluate the emissions perform- ance of vehicles in customers' hands. The next question is the main- tenance required on prospective 1975-76 control systems to achieve compliance in use. This calls for discussion of the procedures neces- sary to ensure proper maintenance, namely the nature and feasibility of required testing and maintenance. The latter depends in turn on the adequacy of the service industry and the interest of state govern- mental bodies enacting required legislation. Perhaps the overriding question is whether adequate consideration has been given to mainten- ance in the design of planned 1976 emission-control systems, most of which involve the use of catalytic converters. 4 2 Differences between Certification Test and In-Use Operation . It is relevant to discuss here some of the more significant differences between the stresses on the emission-control system expe- rienced during certification and during normal customer operation. The driving modes specified in the mileage-accumulation schedule of the certification procedure do not represent all the possible modes encountered in real life. There are some not included, such as sus- tained operation at high engine power and long decelerations, that will provide severe tests for emission-control systems, especially those using catalytic converters. Ford believes the certification test 69 -

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driving does not provide enough mechanical stress on the catalyst, es- pecially if the driving is carried out on an automatically operated dynamometer, which is the usual procedure for the accumulation of mile- age. The vehicles are stopped only for tests every 4,000 miles; in normal use, of course, vehicles stop much more frequently. With cata- lytic systems, catalysts will heat up and cool down several hundred more times in 50,000 miles of normal use than in certification. The New York City Department of Air Resources has also pointed out that the certification procedure does not represent actual driving conditions because of insufficient allowance for the effect of accessories. Sufficient data are not available to fully assess the effects of low-t~perature operation on catalyst durability. However, in- creased loading on the catalysts due to low ambient temperatures, as well as occasional bouts of freezing and thawing, appear to offer in- use conditions that would lead to the necessity for more frequent cata- lyst replacement than during the certification procedure. The durability phase of the certification test should be suffi- ciently demanding to establish that the emission-control systems will perform in the hands of customers. The allowable maintenance in the durability test - one major tuneup in 50,000 miles - was selected to make the test tough and realistic. In real life, much more frequent n~;ntenance will probably be necessary to keep 1975-1976 syst-~,.s within the specified emissions levels, and the Act (Section 207(c)~3~) requires the manufacturers to furnish written maintenance instructions with each new vehicle. Manufacturers are in agreement that more maintenance than Is allowed in the certification test will be necessary in actual use. This is supported by the fact that manufacturers are now requiring more maintenance as a condition of warranty than they were allowed in the certification procedure. In scary, the Committee recognizes that vehicles in customers' hands will not be driven according to the CVS-1975 test procedure, will - 70

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not be driven according to the durability driving schedule, and will not receive the maintenance specified by the manufacturer without rigid enforcement procedures. Therefore, stresses on the systems may be sub- st~ntially greater in customer usage than in certification, and in-use emission levels may thus be correspondingly higher. 4 . 3 Maintenance Procedures Required for 1975-76 Systems Although there are no data on the deterioration of the projec~- ed 1975 -76 control systems in customer use, there are data on the typical deterioration of emission levels from the cars now being driven, These data provide some limited indication of the deterioration as a function of mileage that can be expected to occur with the new systems. Information provided by EPA, California, and ARCO on 1971 and prior model year cars indicates a subs tantial increase in emissions in cus - tomer use. Emissions were found to exceed the applicable standards at relatively low mileage. The most comprehensive surveillance data on the emissions of cars in use have been taken by the California Air Resources Board. Data taken between January and March 1972 showed that 1970 model year cars, with an average accumulation of 32,000 miles, exceed the appli- cable California standards for all three pollutants by amounts ranging from 10 to 60 percent. 1971 model year cars, with an average mileage accumulation of only 13,000 miles, exceeded the applicable standards for at least one of the pollutants. Cars for these model years contain neither catalysts nor much of the other complex hardware proposed by most manufacturers for 1975-76 model years. Further, the applicable standards for California for these model years are many times higher than the federal standards for 1975 and 1976. The dual-catalyst enission-control system proposed by most manufacturers for 1976 model year vehicles is a far more complex sys- tem than that used on current vehicles. Involved are a multitude of - 71 -

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control valves, quick-war-up systems, control circuits, etc., as shown in Figure 3-1. Of all these components, the catalysts themselves appear to be the least durable items. Spark plug misfire, sustained operation at high engine power, and descent down long hi Its are examples of situ- ations that would result in catalyst overheating and pos sible failure. Such vehicle operation and driving modes would not occur in the mileage accumulation specified for the certification test. In addition, there appears to be little incentive for the car owner to maintain the emission-control system. To the contrary, the engirdle will run more efficiently and smoothly with some elements of the emission-control system inoperative. For example, plugging of the EGR system would improve gas mileage, although also increase NO em~s- sions. Increase of choking time would improve vehicle starting charac- teristics, yet also increase cold-start emissions . The importance of adequate maintenance is recognized in Section 207(b)~2~(A) of the Clean Air Act, which requires manufacturers to war- rant their emission-control systems to the purchaser if the vehicle or engine is maintained and operated in accordance with the manufacturer's instructions, and, in the recall provisions of Section 207(c) (1), which empowers the Administrator to recall a class of vehicles or engines if a substantial number of vehicles in each class, although properly ma~n- tained and used, do not conform with the standards. The recall provi- sions could be enforced by relatively frequent analysis of emissions from a sample fleet, carefully chosen for appropriate statistical rep- resentation. Should these give evidence of rapid deterioration of the control system, the recall power provided by Section 207(c) of the Act may then be invoked, with the manufacturer specifically enjoined to replace defective parts, and to defray the associated labor costs at his expense. In this situation, the burden falls not only on the manu- facturer for recall and repair, but also on the car owner, for perform- ing the required routine maintenance and for responding to notifications of recall. - 72 -

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In order to achieve the reduction in automotive emissions anti- cipated by the Clean Air Act, it is apparent that methods must be pro- vided for ensuring proper maintenance of the 1975 and 1976 emission- control systems in public use. Methods of ensuring the required main- tenance include: Requiring the service industry to adjust each car to manufacturer's specifications when performing any maintenance. 2. Periodically testing all cars and designating for adjustment or repair those not meeting pre-selected standards. 3. Periodically subjecting all cars to adjustment or repair. The first method is based on the probability that the manu- facturer's specifications for 1975-76 vehicles will represent adjust- ment to minimum emissions. Mechanics currently adjust cars for high performance. If they continue to do this when manufacturers' specifi- cations are for low-emission adjustments, the cars will emit above the standards. The principal variations in the second method are related to how much of the work is done in state-owned and how much in privately owned facilities, the testing procedure used, testing frequency, pass/ fail standards, provision for retesting after repair/adjustment, and disposition of vehicles that cannot meet the standards. The significant variations in the third method are related to whether the cars are adjusted to some pre-selected standards and whether preventive maintenance is included. Preventive maintenance may be the best feature of this method. Other methods for ensuring the 73

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maintenance of cars in use are probably feasible only if engineering changes, which do not seem likely by 1976, are made. They are: Repair at the time of failure of any important emission- control device based on the presence of devices that signal the failure not only to the driver but also to the traffic officer. Repair at the time of failure of any important emission- control device based on the manufacture of control sys- tems that noticeably degrade the vehicle performance when an important component fails. Prescribed maintenance at predetermined intervals. This method would require strict quality control of the manufacturing process so that essentially every car was held to a configuration proved to give low emissions in actual use. 4 .4 Adequacy of the Service Indus try 4.4. 1 Training The service industry at the present time is not adequate to service 1975-76 cars from an emission control standpoi nt . Knowledge of the devices, the diagnostic equipment, and the number of mechanics are inadequate. The number of vehicles per mechanic in the country has ret sen from 75 in 1950 to 145 in 1970. During the same time, cars have become more complex and less repair-oriented in design. The states that have studied the problem all feel that training on emission-control devices is needed and that the states should be responsible for reco~n- mending suitable equipment. New York plans to certify garages as prop- erly equipped for emission-control work. California licenses mechan- ics' and New Jersey will depend on the promise of large-volume business

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to motivate the private sector to establish its own training and li- censing programs. The service-industry mechanic will have to be trained to understand and perform repairs and adjustments whether or not he performs the complete or partial diagnosis to isolate problems causing excessive emissions. The amount of training will vary slightly with the degree of state control on mechanics, but will generally have to be extensive. 4.4.2 Number of Mechanics The number of mechanics required to maintain 1975-76 emission- control systems will depend upon the interpretation of the 50, 000-mile warranty provision of the 1970 Clean Air Amendments. If the new-car dealerships assume the responsibility and owners are required to bring their cars into the dealers' garages for periodic inspection and main- tenance, a new force of about 12,000 mechanics per year will need to be trained for the dealers, on the assumption that 1975-76 control sys- t~ns will require about two hours more per year than now spent to per- form routine inspection and maintenance. This number of men will need to be added each year for about five years if new-car dealers maintain new cars during warranties: i.e., a new work force of about 60,000 men will be needed by 1980. When warranties expire, experience has shown that most owners will take their cars to garages other than new car dealers; hence, after 1980, an indefinite number of additional mechanics in garages other than new car dealers will need to be trained. The number of mechanics needed in the service industry is difficult to estimate because most of them will probably work only part time on ~~ni s ion control . California is the only state that licenses mechanics to install and repair emission-control devices at this tine. Only a few other states have plans to license mechanics. A Northrop study for the State of California and a similar study by the State of New Jersey have shown that a simple indoctrination of mechanics is not sufficient to obtain cost-effective emission tune-ups. - 75 -

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4.4.3 Equipment The garages in the service industry will need to be sign~ficant- ly upgraded with new equipment to perform diagnoses and tests to deter- mine if vehicles need adjustment or repair and to show that the adjust- ments and repairs were accomplished. The amount of equipment needed will depend partially on whether or not the state operates inspection stations and what kind of inspection test the state performs. However, the state inspection system that would significantly reduce service- industry equipment requirements would be one in which the state would perform the complete diagnosis and instruct mechanics on what parts to replace. r 4.5 State Action 4.5.1 Inspection and Maintenance Systems State governments have been interested in inspection and main- tenance of motor vehicles as a means of reducing exhaust omissions for many years. For example, the New Jersey system, put in operation on July 5, 1972, is the outgrowth of an investigation that started in 1966. It should be noted that even in the New Jersey system, which is the farthest advanced, the features of compulsory maintenance will not be instituted until July 5, 1973. The first year of inspections is being used only to educate the public and elite nate the difficulties . California has required a certificate of compliance from li- censed installation stations since PCV valves were first required in 1963. Idle-exhaust measurement for HC and CO is also now done as part of California's roadside safety inspection. Cars exceeding inspection standards must be taken to a licensed mechanic for adjustment, and a notice that the work was done must be returned by mail. - 76 -

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This interest in inspection/maintenance systems undoubtedly arose from the knowledge that a well-maintained car emits less pollu- tants. A large impetus toward such systems has been added by the real- ization that the manufacture of cars meeting the 1975 and 1976 federal standards is not sufficient unless same system can be found to keep the camp licated emission-control devices operating properly. A survey of the present status of the state efforts to estab- lish inspection/maintenance systems and an investigation of the reasons for the long-time delay in even the most active programs are, therefore, relevant parts of the Committee's investigation of methods of ensuring that the 1975-1976 cars meet the federal standards in actual use. Certain federal action or lack thereof has had a noticeable effect on state action in this field. The Clean Air Act generally preempted motor vehicle emission control for the federal government. This raised several problems connected with the design of state systems. The first is a tendency toward delay; in the few cases in which a state had already started the design, revision was necessary and the states which had not started tended to wait for federal action. Also pertinent are Sections 110 and 207 of the Clean Air Act. Section 110 requires the states to submit a plan for the implementation of the national ambient-air quality standards, and Section 207, deals specifically with motor vehicle compliance. Under the latter, once EPA determines that adequate inspection procedures are available, they are to be established by regulation. Since implementation plans are not yet final for all the states, and since the determination called for by 207(b) has not been made, resulting uncertainty inevitably leads to delays in program planning by the states. The selection of the most suitable method for a state system depends not only on the engineering approach finally adopted by the manufacturers and on the test procedure designated by EPA, but also - 77 -

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on whether the method is to be used only to minimize emissions or also to enforce the warranty on individual vehicles. If the purpose is only to minimize emissions, periodic repair/ adjustment of all cars including preventive maintenance is a possible choice. This approach would require no special inspection facilities owned by the state, but it would require careful surveillance of pri- vately Owned garages and additional equipment in these garages. Requiring the garages to adjust each car to manufacturer's specifications when performing any maintenance also does not require state-owned facilities but does require close supervision. Preventive maintenance could be part of this method and, with this addition, this method only differs from the one first discussed by being voluntary ins teed o f mandatory . Periodic inspection of all cars with measurement of the exhaust emissions and compulsory adjustment or repair of those cars that have emissions exceeding pre-set standards is the method usually meant by an inspection/maintenance system. However, tests other than emissions measurements can be used for inspection in this method. It is normally thought of as occurring annually at the time of license renewal. This system can be operated on three bases: inspection and repair/adjusbment in state facilities, inspection in state facilities and repair/adjust- ment in privately owned garages, and inspection and repair/adjustment in privately owned garages licensed or franchised by the state. The second of the three choices is the usual one principally because of the public distrust of the service industry, which causes the public to pre- fer inspection by the state. The first one is not chosen because of the reluctance of the state to compete with private enterprise and be- cause of the many complications connected with building state-owned repair facilities.

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If the method selected must also include enforcement of the individual car warranty, it we 11 be built around a test yet to be specified by EPA. It is usually assumed that this will be some type of short emissions test, but Section 207(b) of the Act would allow the Administrator to dec ide that functional tes ts on the components corre- lated reasonably well with the results of the CVS-CH test. It is con- ceivable that these tests could be done in privately owned facilities, but the quasi-official nature of the warranty test and its consequences make a state-~wned inspection lane the more obvious choice. If the method includes enforcement of the warranty, EPA will provide the appropriate test; if not, there is wide latitude. Diagnos- tic tests will be part of any system, since such tests and repair/ adjustment cannot be separated, and repair by mechanics is the only operation that provides a direct emission reduction. Inspection lanes select the vehicles needing adjustment or repair but otherwise do noth- ing to reduce emissions unless the results assist or control the me- chanics making the repairs. Inspection lanes can assist and control the mechanics in one or more of the following ways: Detect vehicles with excessive emissions (needing repairs). 2. Detect vehicles with excessive emissions and give a partial diagnosis to help the mechanics get started. 3. Provide a complete diagnosis of repairs needed on vehicles with excessive emissions; and 4. Insure that repairs are complete and correct. - 79 -

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~ study by Northrop Corporation for the State of California found that a schedule of diagnostic tests was not a cost-effective approach to the emission control of used cars. The study showed that exhaust-emission tests by a short dynamometer test (Key Mode) or an idle test gave partial diagnostic information and was more cost-effec- tive. Partial diagnostic information was given to the repair mechanic to assist him ~ n the final diagnosis . The Key Mode and idle approach were reasonably effective for correcting the major emissions problems in used cars. They may not be adequate for controlling 1975-1976 cars to much lower emission levels because there is not yet available a short test that is precise enough to give a pas s or fail that is meaningful in terms of meeting 1975 - 1976 standards. 1975-1976 cars will require a much more thorough diagnosis of the complete emission control system. Diagnostic tests could be useful in inspects on lanes if they provided complete information on engine and control-system failures and operation. This could be accomplished by an automatic and com- puterized diagnostic console, programmed to accomplish quickly and inexpensively one or both of the following: 1. Functional tests showing that the engine and/or the control system are not within specifications where it is known that the combined system will meet the standards. Diagnostic tests showing what parts need to be checked and/or replaced. The mechanics in the service industry could be trained to understand and use the information supplied by the inspection-lane diagnoses . - 80

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4.5.2 Diagnostic Tests at Garages The facilities and equipment of garages can be upgraded to per- form diagnostic tests at periodic intervals. The advantage of this approach is that the mechanics accomplishing the repairs would have first-hand knowledge of the diagnostic test results. Disadvantages of this approach for 1976 vehicles are: Functional NOx catalyst activity tests and NO analyzers have not yet been developed to diagnose NO controls. It may be possible to check the x activity of a reduction catalyst in the oxidizing mode. 2. The engines may need to be loaded in order to produce enough NOx for a meaningful test. Selection of Repair/Adjustment Standards Since the object of an inspection/maintenance system is to reduce the total amount of pollutants emitted to the atmosphere, there is a strong incentive to require repair and adjustment for a high per- centage of the cars found to be over standards. However, as more and more cars are adjusted/repaired, the gain in air quality per dollar spent decreases; i.e., the cost effectiveness decreases. With practi- cal and cost considerations thus limiting the number of cars sent for adjustment and repair, the maximum emissions reduction is to be achieved by adjusting only those cars whose emissions are clearly high and leav- ing alone those below or near the satisfactory level. The percentage of cars sent for adjustment/repair must be con- sidered with great care also because it increases the load on both the service industry and the inspection lanes and because a high percentage of re-rejections will destroy public support, which is so important. _ 8L -

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With the present state of the service industry, a sizable percentage of cars will not meet the standards after the first repair/ad justment if the levels are strict. In addition there is a shortage of mechanics of even reasonable training. If the standards are set to send a high per- centage of cars for repair/ad justment, the number of cars that cannot meet the standards without costly repairs will be so large that it we 11 again affect public support. 4.5.4 Timing and Cost of Inspection Facilities The time and cost required to set up inspection facilities depends to a large extent on the amount and type of related facilities that are already available. Three cases will be considered: Safety-inspection facilities are already available and emissions testing can be added to such facilities. Properly controlled, privately owned service facili- ties are available, with missions testing done at such f acidities. 3. Neither condition 1 or condition 2 exists and in- spection facilities must be built. New Jersey is an example of the first situation and it has proved relatively easy from a physical standpoint to add emissions testing to the state-owned safety-inspection lanes. For the idle test that they are using, equipment costs are about $2,000 per lane. On the assumption that legislative authors ty already exists, it should be possible to put emissions testing in operation in one year. Extra manpower required would be one per lane. No meaningful estimate of operating or capital costs chargeable to the emissions testing is possible because of shared costs. Time and cost would both increase if the testing were also intended to enforce the federal individual car warranty. - 82 -

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California could be an example of the second situation since they license Grade ~ mechanics for various specialties including emis- sion-control devices. The time required in this case should also not exceed one year. Costs for added equipment would again be about $2,000 per station for an idle test. Operating costs would be mixed with adjustment and repair costs and, consequently, a separate estimate is probably of questionable meaning. The third situation has been studied in considerable detail by Northrop-Olson Laboratories and also by TRW. Because of the conditions assumed in this study, the cost results must be qualified although the results do give a good indication of the range to be expected. The land, structure, and equipment will cost from $23, 000 to $60, 000 per inspection lane, with a major portion of the difference in cost caused by the presence or absence of dynamometer equipment. These numbers are approximately confirmed by the TRW study which estimated $44,000 to $52,000 per lane for dynamometer-equipped facilities. Different tests not only use different equipment but they also have different through- puts per lane. Based on these factors, the cost of land, structure, and equip- ment on a one-inspect~on-per-year basis is between $1.30 and $8.80 per car when calculated for Californians population distribution and 10 million cars. Operating costs in 1976 would be between $1.20 and $4.00 per car per year,again under California conditions. The original capital costs are a small fraction of this and they are included with struc- tures amortized over 20 years and equipment over 5 to 10 years. Training time for personnel would be between 90 and 180 hours per man, which includes 40 hours classroom training. - 83 -

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Again on the as gumption that legis lative authority already existed, it would probably take 1.5 to 2 years to acquire land, erect and equip the buildings, and train personnel. At least one year must be added to any of the above time schedules if legislative authority does not already exist. Even more time must be added if an operational plan does not exist; witness the New Jersey and New York experiences. A state just starting would probably be fortunate to have a fully op- erational inspection system in 4 years. In summary, only few states have any semblance of ~ testing/ inspection system that would be adequate to ensure compliance in use. Most states do not even have plans for such systems. The present ser- vice industry is inadequate to maintain the complex emission-control hardware called for with the dual-catalyst system planned for use in 1975-76. With this pessimistic appraisal of feasibility, it is well to consider alternate approaches. 4 6 Incorporate on of Maintenance Considerations in Emission- Control System Design The pessimistic appraisal of the feasibility of vehicles equipped with dual-catalyst control systems meeting the standards in customer use is indicative of a lack of consideration of maintenance in the design of such systems. Fran the data presented in Section 3, it appears that several systems offer maintenance advantages over the dual-catalyst system, although the low-mileage emissions of such sys- terns, on experimental vehicles, may not currently be as low as those of the dual-catalyst system. The three-valve carbureted stratified-charge engine and the Wankel engine with thermal reactor show potential for low emissions without the use of catalysts. HC and CO deterioration factors for the former, at 1975 levels and as measured on the federal driving cycle, are considerably less than those from catalyst-equipped vehicles. - 84 -

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Development work is required on the engine to reduce NO emissions to 0.4 grams per mile; however, such a development effort would seem well worthwhile due to the potential of the engine for reduced maintenance and Improved performance in use over the dual-catalyst system. Systems employing precise control of air-fuel ratio with a feedback loop, discussed in Section 3.6, have several possible ma~nten- ance advantages. Since an air-fuel ratio near stoichiometry results in almost optimum performance, the serious performance and fuel penal- ties inherent in other NOx-control methods would be eliminated; the advantage, from the owner's viewpoint, of an inoperative control system would be removed. In fact, any malfunction of this system might easily degrade vehicle performance so that the owner would be encouraged to get the ~mission-control system fixed. Since such a feedback loop makes the engine essentially self- tuning, this approach should also eliminate a large fraction of the inherent variability between individual vehicles that results from manu- facturing tolerances. Possibly also, operational variabilities that result fray variations in driving habits, fuel consumption, atmospheric parameters, and induction-system deterioration would be largely elimina- ted. Thus a larger fraction of cars would operate as designed and emit less pollutants. Excessive catalyst temperature caused by the simultaneous pre- sence of excess oxygen and large amounts of combustibles would be eliminated since neither rich mixtures nor secondary air is required. Finally, since the system includes an electronic control circuit, in- stallation of signals for malfunctions should be relatively easy. 4.7 Summary Emissions of 1975-76 vehicles in customer usage can be expected to be greater than those measured during certification. Because of the - 85 -

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added emission controls, most vehicle configurations proposed for these years will require more maintenance than at present. For all systems, some additional inspection and maintenance will be necessary to assure that the vehicles are meeting standards in use. Some legal enforcement procedures will be required to assure that necessary inspection and maintenance are performed; otherwise, vehicles will very likely exceed the emis s ion s tandards in use. The service ~ ndustry at the present time is not adequate to service the 1975-76 cars from an emissions standpoint. Only few states have a semblance of a testing/inspection system for emissions that would be adequate to ensure compliance in use. A basic problem in establishing technological feasibility is that maintenance considerations have not been given adequate attention in design. The three-valve carbureted stratified-charge engine, Wankel with thermal reactor, and catalytic system with exhaust sensors and feedback control seem to have far more potential for achieving low emissions in use than the dual-catalyst system currently being proposed by most manufacturers for the 1976 model year. - 86 -