850cc
8A Austin up to 25000
8MB Morris up to 25000
8AM Austin & Morris 25000 onwards
8AH Austin & Morris Automatic
8AJ Austin & Morris closed circuit breathing
8AK Austin & Morris automatic with closed circuit breathing
8WR Wolseley Hornet & Riley Elf
8AC Moke
85H/101 All variants 1969 onwards
Note: third suffix letter denotes compression type, L = Low, H = High, e.g. 8AM/U/H101 denotes high compression.
998cc
9WR Wolseley Hornet & Riley Elf Mk2, pre closed circuit breathing
9AD Austin, Wolseley Hornet & Riley Elf Mk2 with remote type gearbox and closed
circuit breathing
9AE Wolseley Hornet & Riley Elf Mk3
99H/-/101 on Wolseley, Riley, Mini 1000, Clubman1000 1970 onwards and Mk3 with dished
piston
99H/791 Mini 1974 onwards with dished piston
99H/997 1980 onwards A+ block, flat top psitons, economy fitment with 2.95 final drive
99H/A97P A+ block with dished pistons, pre-A+ gears, 3.44 final drive & 12-inch wheels
998 A+ block with centre locating tang in main cap, 1985 onwards
Flat top piston with circlip wrist pin retention
99H/B81 Up to engine number 127431
99H/C20 Up to engine number 105023
99H/997 From engine number 127422 with 2.95 final drive
99H/A35P
Flat top piston with press fit wrist pin
99H/B81 From engine number 127432
99H/C20 From engine number 105024
99H/D80
Flat top pistons with press fit wrist pins, Lead-free cylinder head
99H/G30 or G32 or G33
99H/F15 or F16
99H/E20 or E21
99H/D81
LBB10089
Dished pistons with circlip wrist pin retention
99H/B83P Up to engine number 102908
99H/B84P Up to engine number 100216
Dished pistons with press fit wrist pin
99H/B83P From engine number 102909
99H/B84P From engine number 100217
Dished pistons with press fit wrist pin, Lead-free
99H/G31
99H/E22
LBB10175
1100cc (1098cc)
10AMW/Ta Clubman Estate and Austin 110 (ADO16 shape)
10H791 Clubman saloon
10H/-/H All Austin 1100 2 & 4 door derivative Saloons (ADO16 shape)
10GR/Ta/H MG1100 (ADO16 shape)
10GRB/Ta/H MG1100 & Wolseley 1100 (ADO16)
10V/Ta/H Vanden Plas 1100 (ADO16 shape)
997 Cooper
9F/Sa/H101 to 2637 except 19201 to 20410 (became 1070S)
998 Cooper January 1964 onwards)
9FA/Sa/H Mk1 Austin pre closed circuit breathing
9FD/Sa/H Mk1 Morris up to engine number 1934, all Austin Mk2 closed circuit breathing and
Morris Mk2 from engine number 1935-33660 with closed circuit breathing
9FD/Xe/H 4 syncro gearbox introduced
99/-/H Last of manufacture 1969
Cooper S variants
970cc
9F/Sa/X Engine numbers 29001-29003 with Tecalamit filter
9FD/Sa/X Closed circuit breathing introduced with Tecalamit filter
9FE/Sa/X Closed circuit breathing, oil filter with oil light switch introduced
9F/Sa/X Engine numbers 29039-30029 Purolator oil filter with oil light switch and closed
circuit breathing
1070cc
9F/Sa/H Engine numbers 26501 to 33660 and 19201 to 20410
9FD/Sa/H Engine numbers 33661 to 33948 with closed circuit breathing and oil light switch in
oil filter head
1275cc
9F/Sa/Y Engine numbers 31001 to 31504 pre closed circuit breathing with Purolator oil filter
9FD/Sa/Y Closed circuit breathing with oil light switch on filter housing after engine number
32178
9FE/Sa/Y Closed circuit breathing with oil light switch on Purolator filter housing and piston
design change
9F/Sa/Y From engine number 32378 onwards, cosed circuit breathing with Purolator filter
with oil light switch, Aeg510 camshaft introduced at engine number 40006, cross-
drilled EN40Bcrank at engine number 42730 and metal dipstick tube at engine
number 42548 onwards
12H397 Cooper S Mk3 with dynamo, negative earth and Tuiftrided EN16T crankshaft
12H398 Cooper S Mk3 with alternator, negative earth and Tuftrided EN16T crankshaft
Note: Only Cooper S engines with prefix '9F' had EN40B forged steel, nitrided crankshafts. All other A-series engines had EN16T steel crankshafts which were only Tuftrided on Mk3 'S' and Austin 1300GT (ADO16) and were stamped 12G1683.
1275cc, Solid wall block (no tappet chest covers)
12G/Ta/H ADO17 shape Wolseley, Riley, MG & Vanden Plas fitted with S rods
12H379 1275GT with dynamo, negative earth, electric fuel pump and remote type gearbox
12H380 1275GT with alternator, negative earth, electric fuel pump and remote type gearbox
12H389 1275GT with dynamo, negative earth, mechanical fuel pump and remote type gearbox
12H390 1275GT with alternator, negative earth, mechanical fuel pump and remote type gearbox
12H706 1275GT with alternator, negative earth, mechanical fuel pump and rod changegearbox
12H397 Cooper S Mk3 with dynamo and negative earth
12H398 Cooper S Mk3 with alternator and negative earth
12H/-/ 1275 Austin ADO16 & Allegro
12H610/635 Innocenti Mini with duplex cam drive gears and 11-stud head
12H719/832 Innocenti Mini with simplex cam drive gears and 11-stud head