123/MG-4-R-V for MGA and MGB (negative ground)
The 123/MG-4-R-V is designed specifically for the MGA and MGB, both negative ground! All the advance-curves, that were EVER specified for these cars, are integrated into this product. In addition, there is a fine-tuned curve for the so called 'stage-two' engines too!
The 123/MG-4-R-V is designed specifically for the MGA and MGB, both only negative ground!
All the advance-curves, that were EVER specified for these cars, are integrated into this product. In addition, there is a fine-tuned curve for the so called 'stage-two' engines too!
Static-timing is on TDC for all MGB-engines.
For a MGC please order a 123/GB-6-R-V.
The unit offers:
- Vacuum-advance
- Automatic dwell
- Automatic power-cut after 1 second
- Gear shift retard
Please read the installation manual carefully. It contains more information on the motor- and distributor numbers, static timing and the advance-curves (often found on the last page), the specifications of the 123ignition and a step-by-step description of the installation procedure.
Note: Although used coils all look alike, they should be viewed with suspicion since one cannot tell from the outside whether, and how often they were exposed to overheating in the past. Installing the 123ignition system will ensure that the coil will never be overheated again in future. We recommend the 123 Blue Coil.
Perhaps you'll also need new spark plugs? At 123ignitionshop we recently added the spark plugs most commonly used in combination with the 123ignitions we offer. See: the spark plugs list.
Complete set
Now also the complete set can be ordered in one go: a 123/MG-4-R-V distributor + 123 Blue Coil + set of 4 spark plugs WR7DC + spark plug cables
Data sheet
- Cylinders
- 4
- Direction of rotation
- CW/CCW
- Voltage
- 4,0 - 15,0 volts
- Range
- 500 - 8000 rpm
- Temperature
- -30 to 100 Celsius
- Coil
- Stock or high energy coil, primary coil NOT below 1,0 ohm
- Dwell
- Constant current, fully automatic
- Time-out
- After 1 second current is switched off
- Accuracy
- Less than 0,5 degr. crankshaft
- Vacuum
- With vacuum, also works without when not connected.
- Max. Advance
- 45 degr. crankshaft
- Wiring
- red +6V of +12V, black - coil
123 mg 4/r/v
Thank you so much .I've just fitted the 123 distributor to my 1970 mgb gt the car now runs far better and smoother than it ever has.looking forward to clocking up many more miles.
The best you can get
I purchased the 123/MG-4-R-V for my 73 MGB Roadster and what a good choice, not cheap but well worth it, easy to fit with good instructions and back up, I think the 123 is the best you can get if you want trouble free motoring.
Bon produit
Good item, easy to fit and easy to adjust, what I appreciate also :
- strength of the spark, associated with the Bosch Blue coil
- and also : speedness, information and support from 123Ignitionshop
At last a reliable replacement!
My wife has owner her 1972 MGB for 37 years and at last we can feel confident that not only will it start easily, but will also keep going!
Easy to fit and looks original, but shows how much car electronics has improved over the years.
I have no hesitation in recommending 123ignitionshop, their service was faultless, rather like their product.
very good product
Since installing the 123 ignition system in my 1971 MG B, the car is performing very well. The power has increased, the economy has improved, the car starts first time, there is no overheating, and no 'running on'. The new electronic ignition, which my son and I fitted from the very clear instructions, has given new heart to the old car, and it feels much more robust, but still retaining the character of the MG. Thank you LEEN APK, I would definately reccomend this product to other classic car ownwers
Curve | Advance starts (rpm crankshaft) |
Max. advance (rpm / degree crankshaft) |
Vacuum advance starts (mmHg) |
Vacuum advance ends (mmHg / degr.) |
Replaces | Remark |
0 | 500 | 2200 / 28,0 | 100 | 300 / 18,0 | MG-A DM2 / 40510 | set static at -10 degrees HC @ -5 degr |
1 | 500 | 4400 / 24,0 | 100 | 300 / 16,0 | 40916 | 18GG (LC), 18G, 18GA, 18GB, 18GD |
2 | 500 | 2200 / 20,0 | 130 | 330 / 20,0 | 40897 / 41155 | 18G, 18GA, 18GB, 18GD, 18GG(HC), 18GF, 18GH, 18GJ |
3 | 1000 | 4600 / 20,0 | 100 | 300 / 10,0 | 41339 | 18GK |
4 | 1000 | 4500 / 20,0 | 100 | 300 / 10,0 | 41370 | 18G584Z, 18G585Z |
5 | 1000 | 4300 / 33,0 | 100 | 300 / 10,0 | 41491 | 18V672Z, 18V673Z |
6 | 700 | 2200 / 14,0 | 130 | 330 / 20,0 | 41288 |
18V581F, 18V583F, 18V581Y, 18V583Y (HC) |
7 | 700 | 4200 / 18,0 | 100 | 300 / 16,0 | 41290 | 18V581F, 18V583F, 18V581Y, 18V583Y (LC) |
8 | 700 | 2200 / 19,0 | 75 | 200 / 14,0 | 41032 | 18V (HC) |
9 | 1000 | 6000 / 27,0 | 100 | 300 / 16,0 | 41234 / 41391 / 41692 | 18V892AE, 18V779F, 18V780F, 18V893AE |
A | 1000 | 5800 / 24,0 | 75 | 550 / 24,0 | 41610 | 18V846F, 18V847F |
B | 1000 | 5000 / 26,0 | 100 | 300 / 10,0 | 41599 | 18V797AE, 18V798AE |
C | 1000 | 4400 / 22,0 | 100 | 300 / 10,0 | --- | intended for ‘stage 2’ engines |
D | 1000 | 4500 / 29,0 | 100 | 300 / 10,0 | 41600 / 41643 | 18V801AE[CC], 18V802AE[CC] |
E | 1000 | 4500 / 29,0 | 100 | 300 / 10,0 | 41693 | 18V883AE[CC], 18V884AE[CC] |
F | 1000 | 4500 / 29,0 | 100 | 300 / 10,0 | 41695 | 18V890AE[CC], 18V891AE[CC] |