[Code of Federal Regulations]
[Title 40, Volume 17]
[Revised as of July 1, 2004]
From the U.S. Government Printing Office via GPO Access
[CITE: 40CFR86.335-79]
[Page 608-609]
TITLE 40--PROTECTION OF ENVIRONMENT
CHAPTER I--ENVIRONMENTAL PROTECTION AGENCY (CONTINUED)
PART 86_CONTROL OF EMISSIONS FROM NEW AND IN-USE HIGHWAY VEHICLES AND
ENGINES--Table of Contents
Subpart D_Emission Regulations for New Gasoline-Fueled and Diesel-Fueled
Heavy-Duty Engines; Gaseous Exhaust Test Procedures
Sec. 86.335-79 Gasoline-fueled engine test cycle.
(a) The following test sequence shall be followed in dynamometer
operation tests of gasoline-fueled heavy-duty engines. Diesel engines
are covered in Sec. 86.336.
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Observed
torque Time in Cumulative
Cycle No. Mode No. Mode (percent of mode- time- Weighting
maximum seconds seconds factors
observed)
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1........................................ 1........................... Idle....................... ........... 60 60 0.232
1........................................ 2........................... Cruise..................... 25 60 120 .077
1........................................ 3........................... PTA........................ 55 60 180 .147
1........................................ 4........................... Cruise..................... 25 60 240 .077
1........................................ 5........................... PTD........................ 10 60 300 .057
1........................................ 6........................... Cruise..................... 25 60 360 .077
1........................................ 7........................... FL......................... 90 60 420 .113
1........................................ 8........................... Cruise..................... 25 60 480 .077
1........................................ 9........................... CT......................... ........... 60 540 .143
2........................................ 10.......................... Cruise..................... 25 60 600 .077
2........................................ 11.......................... PTA........................ 55 60 660 .147
2........................................ 12.......................... Cruise..................... 25 60 720 .077
2........................................ 13.......................... PTD........................ 10 60 780 .057
2........................................ 14.......................... Cruise..................... 25 60 840 .077
2........................................ 15.......................... FL......................... 90 60 900 .113
2........................................ 16.......................... Cruise..................... 25 60 960 .077
2........................................ 17.......................... CT......................... ........... 60 1,020 .143
2........................................ 18.......................... Idle....................... ........... 60 1,080 .232
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(b) Except for idles, the engine dynamometer shall be operated at a
constant speed of 2000 rpm100 rpm. Speed
deviations, not to exceed 200 rpm, will be allowed during the first 10
seconds of each mode.
(c) The times in-mode specified in paragraph (a) for the CT modes
are 2 seconds. All other times in-mode are 4 seconds.
(d) The first 35 seconds of each 60 second engine power mode is
allowed for engine-dynamometer stabilization. After this stabilization
period the torque must be held at the specified value 5 percent until the exhaust gas analysis period. During
the exhaust gas analysis period, the last 10 seconds of each nonclosed
throttle mode the engine torque must be at the specified value 2 percent of the maximum torque observed. For example,
mode 3 torque shall be held between 53 and 57 percent of maximum torque
(552 percent) during the exhaust analysis period.
Prior to the analysis period but excluding the first 35 seconds of the
mode, the torque shall be held between 50 and 60 percent of maximum
torque (55%5%).
(e) The idle operating mode shall be carried out at the
manufacturer's recommended curb-idle engine speed. Arrive at the last
idle mode by closing the throttle, braking the dynamometer to the engine
idle speed, and unloading the dynamometer.
(f) The CT operating mode shall be carried out at the same engine
speed as specified in paragraph (b) of this section.
(g) If the Administrator determines that an engine shall be tested
as an automatic transmission code engine, then a load shall be applied
by the dynamometer during the idle modes (1 and 18) such that the engine
speed is decreased from the recommended dynamometer-idle speed to the
recommended curb-idle speed. The engine
[[Page 609]]
idle torque recorded for the calculations in Sec. 86.345 shall be zero.
(h) If the operating conditions specified in paragraph (a) of this
section for modes 2 through 8, and 10 through 16 cannot be maintained,
the Administrator may authorize deviations from the specified load
conditions. Such deviations shall not exceed 5 percent of the maximum
torque at the test speed. The minimum deviations, above and below the
specified load, necessary for stable operation shall be determined by
the manufacturer and approved by the Administrator prior to the test
run. Emission tests shall be performed by operating the engine at the
higher approved load setting during cycle 1 and at the lower approved
load setting during cycle 2. The weighting factors shall be as specified
in paragraph (a) of this section.
(Secs. 206, 301(a), Clean Air Act as amended (42 U.S.C. 7525, 7601(a)))
[42 FR 45154, Sept. 8, 1977, as amended at 44 FR 16917, Mar. 20, 1979;
47 FR 49813, Nov. 2, 1982]