Engine and Bore Size | Ring including oil ring and ring size |
Ring Hepolite part number. | Rings Rover part number STD/20 only | Piston Part Number | Piston shape | Remarks |
---|---|---|---|---|---|---|
850cc 62.916mm 2.477” STD 20/ 30/ 40/ 60 |
4. 3 x 0.0700” 1.778mm 1 x 0.1250” 3.175mm |
RA8576 |
BHM1161 |
12A120 |
|
Use 15037 |
5. 3 x 0.0700” 1.778mm 1 x 0.1248” 3.170mm 1 x 0.1250” 3.175mm |
RA8577 |
|
15037 |
|
|
|
Cooper - 997cc 2.458” - 62.43mm STD 20/ 30/ 40/ 60 |
4. 3 x 0.0625” 1.588mm 1 x 0.1250” 3.175mm |
2C6724 Hastings ring |
|
12A212 15799 18515 |
|
|
Cooper 998cc 2.542”-64.567mm STD 20/ 30/ 40/ 60 |
3. 2 x 0.0625” 1.588mm 1 x 0.1575” 4.000mm |
R39400 can use R33636 |
|
20950 was 18516 |
Flat top 20950 9.7 CR |
Powermax Rings also fit 18516 |
4. 3 x 0.0625” 1.588mm 1 x 0.1250” 3.175mm |
R32026 or C-STN99 |
BHM1162 |
12A674 |
Flat top with raised ‘D’ |
|
|
998cc 64.567mm 2.542” STD 20/ 30/ 40/ 60 |
4. 3 x 0.0625” 1.588mm 1 x 0.1250” 3.175mm |
R32026 or C-STN99 |
BHM1162 |
12A673 / 16309 |
Dished piston 8.3 |
To 1979 |
4. 3 x 0.0625” 1.588mm 1 x 0.1575” 4.000mm |
R33636 |
BHM1281 |
ADU3920 20754 |
Flat top 10.3 to 1 CR |
1980 on, until changed to 3 ring piston |
|
4. 3 x 0.0625” 1.588mm 1 x 0.1575” 4.000mm |
R33636 |
BHM1281 |
ADU3922 20773 |
Dished 8.3 to 1 CR |
||
3. 2 x 0.0625” 1.588mm 1 x 0.1575” 4.000mm |
R39400 can use R33636 |
BHM1415 |
ADU3490 |
Flat top 10.3 to 1 CR |
3 ring pistons up to introduction of press fit gudgeon pin, 1988 |
|
3. 2 x 0.0625” 1.588mm 1 x 0.1575” 4.000mm |
R39400 can use R33636 |
BHM1415 |
ADU4203 20536 |
Dished 8.3 to 1 CR |
||
3. 2 x 0.0590” 1.499mm 1 x 0.1181” 3.000mm |
BHM1629 |
TAM2052 (Rover) P22463 (AE) |
Flat top stamped 21964 |
Press fit gudgeon pin only 1989 on |
||
3. 2 x 0.0590” 1.499mm 1 x 0.1181” 3.000mm |
R43240 |
TAM2054 (Rover) 22464 (AE) |
Dished stamped 21965 |
|||
1100cc 64.567mm 2.542” STD 20/ 30/ 40/ 60 |
4. 3 x 0.625” 1.588mm 1 x 0.1249” 3.172mm |
R32026 or C-STN99 |
BHM1162 |
12G758 use 20397 |
|
Morris Minor/ Mini/ MG 1100/ Sprite Clubman 1975-1980 |
5. 3 x 0.0625” 1.588mm 2 x 0.1250” 3.175mm |
R17927 |
|
Not Mini 16179 |
|
Morris Minor/MG 1100/Sprite 5 ring 1975-1976 |
|
4. 3 x 0.0625” 1.588mm 1 x 0.1575” 4.000mm |
R33636 20397 |
BHM4418 |
|
Dished 20397 |
Morris Minor MG 1100/Sprite |
|
1275cc 70.625mm 2.780” STD 20/ 30/ 40/ 60 |
4. 3 x 0.0625” 1.588mm 1 x 0.1575” 4.000mm |
R21576 |
BHM1164 |
17271 (AE) |
1275GT and 1275cc non ‘S’ |
|
4. 3 x 0.0625” 1.588mm 1 x 0.1575” 4.000mm |
R21576 |
BHM1284 |
20394 (AE) |
Dished 8.8 CR |
1275GT and 1275cc non ‘S’ |
|
3. 2 x 0.0591” 1.501mm 1 x 0.1575” 4.000mm |
R35960 |
|
Dished 8.8 CR |
Latest metric sized piston 1275 GT 1970-1975 |
||
4. 3 x 0.0469” 1.191mm 1 x 0.1575” 4.000mm |
R19520 |
BHM1165 STD/20 oversize |
AEG143 |
Dished 9.7 CR | Original ‘S’ and 1300GT. Use 21253 |
|
3. 2 x 0.0625” 1.588mm 1 x 0.1575” 4.000mm |
R26686 use R21576 |
BHM1166 |
19320 |
Dished 9.7 CR |
Later ‘S’ and 1300GT / 1275GT |
|
3. 2 x 0.0591” 1.501mm 1 x 0.1181” 3.000mm |
R41570 C1818 (Steel ring upgrade) |
BHM1628 |
21253 (AE) TAM2050 (Rover) |
Dished 9.7 CR Stamped 21962 |
Metric sized pistons Dished 10.1 CR |
|
3. 2 x 0.0591” 1.501mm 1 x 0.1575” 4.000mm |
R35960 |
|
21250 (AE) TAM2048 (Rover) |
Dished 9.4 to 1 CR Stamped 21963 |
Metric sized pistons |
|
3. 2 x 0.0625” 1.588mm 1 x 0.1575” 4.000mm |
Use R21576 |
BHM1260 |
ADU5704 was P22357 |
Turbo Dished 9.4 to 1 CR Known as 21254 |
Use P223575 + 40 only available |
|
2 x 0.0470” 1.194mm 1 x 0.1575” 4.000mm |
C-AJJ3379 |
|
ADU5704 was P22357 |
Turbo Dished 9.4 to 1 CR | P223575 + 40 only AE MEGA type |
|
2.780” 70.625mm Powermax STD +20/40/60 |
3. 2 x 0.0469” 1.191mm 1 x 0.1575” 4.000mm |
R39380 C.W.E Can use R19520 |
|
18517 18518 |
Dished 9.7 CR Flat top |
Forged, use 20747 Use 21882 |
3. 2 x 0.0469” 1.191mm 1 x 0.1575” 4.000mm |
R39380 C.W.E Can use R19520 |
|
20747 |
6.6cc Dish 9.7 to 1 CR |
AE413 Squeeze cast - 16906 |
|
3. 2 x 0.0469” 1.191mm 1 x 0.1575” 4.000mm |
R39380 C.W.E Can use R19520 |
|
20739 |
Flat top |
Squeeze cast, use 21882 |
|
3. 1 x 0.0394” 1.000mm 1 x 0.0469” 1.191mm 1 x 0.1181” 3.000mm |
R41720 |
|
21882 |
Flat top |
Squeeze Cast | |
AE-MEGA / OMEGA 2.780mm |
2 x 0.0470” 1.194mm 1 x 0.1575” 4.000mm |
C-AJJ3379 |
|
C-AJJ3378 AE/MEGA C-AJJ3382 AE/MEGA |
Dished Flat top |
OMEGA are Hi-grade cast light alloy. AE MEGA were squeeze cast - now new technology castings, FM-B2 material double heat treated |
AE-MEGA / OMEGA 73.5mm |
2 x 0.0470” 1.194mm 1 x 0.1575” 4.000mm |
OMEGA R73.5 |
|
See special tuning |
7cc dish - C-STR310 11cc dish - C-STR312 |
|
Powermax 73.5mm 1275 to 1380cc |
2 x 0.0591” 1.501mm 1 x 0.1575” 4.000mm |
R39390 |
|
P20659 (AE) C-STR311 (Minispares) |
Dished 9.6 CR 9cc Dish |