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    3-pin and 6-pin DC-boxes of Raceservice4u are new built in a Bosch style die-cast case. All electronic parts and circuit board are like original specifications or better. The construction allows replacement of components in case of damage for whatever reason.  


    Most 40 year old original boxes suffer of bad performance at high revs and temperatures higher than 60 degrees. In most cases it is the thyristor and condensor. Or corrosion of parts. connections and circuit board. 
    You can  have to less spark energyfor firing the mixture above 6500 RPM. For road cars is that OK but not for a race car. It is therefore advisable to bring in your 3/pin and 6/pin boxes for service.

    Rev limiter built in both boxes is possible.




    The 8-pin is not only bigger, has more components and connections, but the performance is far better than the 3 or 6 pin box. With increasing RPM the 8-pin the spark will have a constant energy up to more than 9000 RPM. The speed in which the spark starts and reaches its maximum is faster than with the 3 or 6 pin boxes. Important is the spark energy see above a graphic for the difference between the Bosch boxes.




    The coils

    Raceservice4u has black  coils made in USA .
    The silver canBosch coil made in Brazil are coils with many problems; as you find them on many internet forums.

    The ratio is 1/100 and produced spark energy depends on the energy (mJ)

    delivered by the CD-box.


    The Raceservice4u coil Specifications; 

    • High Performance, Canister type Coil small length and colors like the original Bosch Coil.
        Epoxy Potted for High Vibration
        Inductance: 8 mH
        Primary Resistance: 0,7 Ohms
        Turns Ratio: 100:1
        Secondary Resistance: 139 Ohms
        Maximum Voltage: 45,000 volts



    The in house produced wireloom is made with wire shield wires for reduction of interference with the Plug wires. The wireloom is made for best possible positions of the CD-boxes and coils. .

    Raceservice4u advice to use the same positions in the engine bay as was used in the time period.  With this layout the signal cables will be as far as possible away from the Plug wires to prevent interference between them.


    The Plug wires are made of 8mm double isolated, suppressed cable with spiral core.


     Copyright Jan van Elderen