Mounting instructions for the '123ignition'
type : 123\MINI-R-V & 123\MINI-R-V-A+ for : all 6 & 12 Volt cars, negative earth only !
STEP 1: Find the static timing point
On the old distributor, note the position of the ignition wire to the number one cylinder. Number one is beside the radiator and the firing order is 1-3-4-2. Remove the distributor cap and turn the engine in its normal direction so that the rotor almost points to the number one cylinder position, ie the 2 o’clock position.
Now carefully turn the engine further until the Top Dead Center ( TDC ) is indicated on the timing mark on the flywheel. The engine is now at the static timing point, at the end of the compression stroke for the number one cylinder.
STEP 2: Out with the old, in with the new
You may wish to verify that the correct advance curve has been selected in your '123' : using a 5mm Allen wrench remove the hexagonal plug in the bottom face of the housing. Inside the hole you'll find a 16 position rotary switch. ( marked '0' to 'F' ) Check the technical data below for the proper setting. Select the curve of your choice ; re-insert the plug and tighten securely. Now remove the spark plug wires and coil wire from the old distributor-cap and remove the old cap. Disconnect the points wire from the coil. Loosen the clamp at the base of the distributor and pull the old unit out.
Now remove the distributor-cap from the '123' and carefully insert the '123' in the block, turning the rotor until the drive dog mates and the unit slips into place. Rotate the housing of the '123' so that the cables come out conveniently, usually with the vacuum port pointing towards number three cylinder.
If necessary, the drive gear can be repositioned on the shaft to accommodate a different rotational position. To do this, remove the '123' and carefully remove the retaining spring from the drive gear, then use a small punch to tap out the pin and re-assemble at an angle more suitable to your needs.
STEP 3: Static timing the '123'
Connect the red wire to the BAT (positive) terminal of the ignition coil, according to the schematic. For now, do NOT connect the black wire. Turn on the ignition. Slowly turn the housing of the '123' in a clockwise direction until the green LED just lights up.
The LED shines through one of the four holes in the aluminum disc below the rotor. While turning, also press the rotor in a clockwise direction, to remove any free play in the drive. Finally, tighten the '123' securely, as it is also the electrical ground of the '123'. Turn off the ignition.
STEP 4: Finish the wiring
Connect the black wire to the negative terminal of the ignition coil, according to the schematic.
Connect the spark plug leads in the proper sequence to the cap, starting with the wire for the number one cylinder at the position pointed to by the rotor of the '123', usually the 2 o’clock position. The firing order is 1-3-4-2 and rotation is counter clockwise.
Also connect the high voltage wire from the coil to the center position of the cap. Attach the cap to the distributor. Route the red and black wire well away from the high voltage leads and away from moving parts, using tie-wraps or other suitable means. Connect the vacuum-tube from the carburetor to the vacuum port on the ‘123’.
STEP 5: Start and test drive
You can now start your engine. If you have worked accurately, your ignition should be adjusted well enough to take a test drive. To achieve ultimate accuracy a fine adjustment using a stroboscope should be performed. ( check the dynamic timing data in 'technical data' ) Disconnect the vacuum-tube whilst fine-tuning. Enjoy your 123ignition!
Bosch cap ref. nrs. : 1.235.522.050 / 1.235.522.058 / 1.235.522.059 / 1.235.522.145 Bosch rotor ref. nr. : 1.234.332.024
In the table presented below, you can see that the 16 curves are divided in four groups of four curves. Each group has a different maximum advance ( 28, 30, 32 & 34 degrees), and the 4 curves within each group have different rates of advance up to 2000 rpm.
Assume you want to tune your engine, and you know the maximum advance for this engine is 30 degrees. The first curve you should choose is curve '4', and if that works well, step to curve '5' for improved throttle response.
If curve '5' is an improvement, you may try curve '6', but listen carefully for evidence of knock under heavy load. If curve 6 is an improvement, select curve 7 and again listen carefully for evidence of knock under heavy load. If knock is detected, step back to the last curve. Engines run under sustained knock conditions can be severely damaged!
If you have any doubt about tuning, please seek advice from a knowledgeable engine tuner, or visit www.TDCperformance.ca for further information.
Operating voltage 4,0 to 15,0 Volts, negative earth only
RPM range 600 to 7000 rpm
Temperature -30 to 85 degrees Celsius
Coilstock coil or "High Energy"-coil, primary resistance not below 1 ohm.
engines all MINI engines ; advance-curves selectable by a switch through the bottom of the housingCurve Advance Advance maximum (switch setting) 500-1000 rpm* @ 2000 rpm* @ 5000 rpm*
0 10,0 14,5 28 1 10,0 16,7 28 2 10,0 18,4 28 3 10,0 20,2 28
4 10,0 16,3 30 5 10,0 17,6 30 6 10,0 19,4 30 7 10,0 21,1 30
8 10,0 16,2 32 9 10,0 18,1 32 A 10,0 20,3 32 B 10,0 22,9 32
C 10,0 17,0 34 D 10,0 20,4 34 E 10,0 22,1 34 F 10,0 23,9 34
* degrees advance and engine speed both relate to the crankshaft
vacuum-advance 0 to 14 degrees from 5 to 10 inch Hg
dwell microprocessor controlled, depending on coil current
current-timeout after +/- 1 second. If the engine is not running, the current is switched off to prevent overheating of the coil
spark balance software controlled, better then half a degree crankshaft
wiring red = +12 Volt
* These engines require more maximum advance than the 123/Mini can provide, but curve F should allow the engine to operate well.