Nissan A Engines: Overview | A10 | A12 | A12A | A13, old | A13, new | A14 | A15
A12A engine (1237cc) was used 1978-1982. A12A debuted 1977 in Japan and 1978 in North America B310. In Japan it was used in sedans & coupes (vans continued to use the A12). It has a 75mm bore, larger than the A12 (1171cc) engine with 73mm bore. The A12A block is virtually identical to the original 1974 A12 using a block casting similar to the A12 but with a 75 mm bore (up from 73 mm) for an increase of 66 cc capacity.
Contents |
Overview
A12: 73 mm bore A12A: 75 mm bore A13: 76mm bore
The A12A uses the "short deck block" design as the A12 and same stroke as the A12, but uses 75mm bore instead of 73mm. NOTE: bore of the A14 and A15 is 76mm. reference: Nissan Competition catalog. The A12A is not to be confused with the Japan/Australia A12 from 1974 up. The "A12A" is the official designation used by Nissan for the 1977-1982 1237cc engine.
Question: Can a regular A12 engine be bored out to 75mm?
Answer: Yes, in fact Datsun even recommended it for oversize rebuilds. Standard A series piston oversizes are 0.5mm, 1,0mm, & 1.5mm — so A12 blocks can be safely bored to 77.5mm. See Bored.
A12A comparison data
12200-H8500 CRANKSHAFT ASSY B310 A12S, A13S
12200-H1000 71-73 A12 (superceded by H8500)
12200-H5001 A12 -7909 (replacement but different)piston w/pin
12010-H8661 A13 std 8011-
12010-H9022 all Canada A12A, USA 0879-0780
12010-H9512 USA A12A 0880-Rod
12100-H8500 A12, A13, A12A
12100-H1000 71-73 A12
The A12A shared a common block and crankshaft with the redesigned A12 and A13 engines. Although referred to as "A12" and "1200" in most Datsun literature, it was explicitly stamped 'A12A' on the engine ID pad. In the Japan market both engines were used at the same time, with A12 fitted to B310 wagons and A12A fitted to B310 Sedan & Coupe.
A12: 1970-1973 with old-style engine mounts A12: 1974-1994 new style engine mounts A12A: 1978-1982 new style engine mounts
Identification
Engine compartment ID Plate
JDM B310 | USA B310
Applications
B310 * 1979 'Datsun Sunny 210' B310 Canada * 1980-1982 'Datsun 210' B310 USA and Canada * 1977-1980 Datsun Sunny B310 Japan and Asia markets S,K only (replaced by the new A13 for 1981/1982) Van (VB310) used A12, not A12A Wagon (WB310) used A14 and A15, never A12 or A12A
Specifications
* 58 HP * 1237 cc (A12 is 1171 cc) * 75 mm bore (2mm larger than A12) * 70 mm stroke (same as A12) * 19.7 mm piston pins (same as A14) * New (A14 style) manifold bolt pattern
B310 with A12A - Japan Market sedans & coupes
Part Numbers
All part numbers are for B310 unless noted otherwise.
H65 = A12 H85 = A12A H86 = A13
CYLINDER BLOCK ASSY 11010-H8500 * A12A JAP 7712-8010 * A12A CAN 1278-0779 11010-H8502 A12A CAN ^11010-H8500 11010-H9001 A12A CAN 0879- °11010-H8502 11010-H9960 A12A USA 0879-
Connecting Rods 12100-H8500 B310 A12A/A13S CONNECTING ROD JAP,USA,CAN * for use with 19 mm piston pin (same as A14)
Head Gasket [75 mm bore] 11044-H8501 JAP A12 S,K 7712-8010 11044-H8501 CAN A12 1979-1980 11044-H8501 USA A12 1980 11044-H9520 USA/CAN 1981-1982 <> 11044-H9521
Cylinder Head (round port) 11041-H8500 JAP A12S.S,K 7712-7909 11041-H8501 JAP A12S.S,K 7910-8010 NOTE H72 same as A14/A15 CAN/KFU round port 11041-H7283 0278-1078 11041-H7284 CAN 1278-0780 <> 11041-H7283 11041-H7285 CAN 0880- <x> 11041-H7284 11041-H9901 FED 0879-0780 11041-H8700 FED 0880- 11041-H9911 CAL 0879-0880 <> 11041-H9911 * same as early CAL A14/A15 round port 11041-H8700 CAL 0880- Piston Set with Pin 12010-H8511 JAP A12S.S,K 7712-7909 STD 12014-H8514 JAP A12S.S,K 7712-7909 OS=0.50 12014-H8516 JAP A12S.S,K 7712-7909 OS=1.00 12010-H8521 JAP A12S.S,K 7910-8010 STD 12010-H8524 JAP A12S.S,K 7910-8010 OS=0.50 12010-H8526 JAP A12S.S,K 7910-8010 OS=1.00 12010-H9012 USA 0879-0780,CAN ALL YEARS <> 12010-H9022 <> 12010-H9001 12010-H9502 USA 0880- <> 12010-H9512
Piston Ring Set (JAP,USA,CAN) 12033-H8500 STD 12035-H8500 OS=0.50 12037-H8500 OS=1.00
Crankshaft 12200-H8500 A12,A12A,A13S <> 12200-H5001 (A12) * supercedes old part
Intake Manifold 14003-H8550 JAP A12S.S,K 7712-7909 [wet type,round port] 14003-H8551 JAP A12S.S,K,7910-8010 > 14003-H8550 [wet type,round port] * also fits JAP A13S 8011- 14003-H9160 CAN 14003-H9900 USA 0879-0780 <> 14003-H9950 14003-H9500 USA 0880- <> 14003-H9550
Exhaust Manifold [3-Bolt flange] 14004-H8501 JAP A12S,A14S.S,K+AT 7712-8010 * was also fitted to C120.A14.K 7810-8006 14004-H7239 CAN 14004-H9900 FED 0879-0780 14004-H9910 CAL 0879-0780 14004-H9501 USA 0880-
14035 Manifold Gasket [round port] 14035-H8501 JAP A12S.S,K 7712-8010 [wet type] * was also fitted to B310 A13S 8011- B120 8910- C22 A12 8509-9111 TC22 A12S 8811-9111 14035-H7400 CAN [dry type] 14035-H8501 USA [wet type]
Emission Controls
Specific carburetors were fitted by year/engine/market
EGR with Air Induction System was fitted to A12A JAP * A12 (Van) had EGR but not AIS
Carbon Canister was fitted * van came with Flow Guide Valve
Catalytic Converter was fitted * van was fitted with resonator