Accuspark is the established budget-friendly electronic-ignition conversion brand, with a product range built around direct-fit replacement kits that drop into existing Lucas distributors with no modifications to the distributor body or to the rest of the ignition system. For owners who want electronic ignition's reliability benefits without the cost of a complete distributor replacement, Accuspark is typically the appropriate choice.
How the Accuspark Kit Works
The Accuspark kit consists of two principal components, a base plate that mounts in the distributor body in place of the original points base plate, carrying a Hall-effect sensor that detects the rotating shaft position; and a small magnet ring that fits onto the distributor shaft, providing the trigger pulses that the sensor detects. As the distributor shaft rotates, the magnet ring rotates past the sensor, producing a series of electrical pulses that signal the coil to fire. The trigger replaces the mechanical opening of the points, eliminating the wear surfaces and the periodic gap adjustment that points ignition requires. The conversion preserves the existing distributor body, cap, rotor arm, advance mechanism and shaft, only the internal trigger mechanism changes.
Installation and Compatibility
Accuspark installation is straightforward. The distributor cap is removed, the rotor arm is lifted off, the points and condenser are removed from inside the distributor (typically held by a single screw on the points base plate), and the Accuspark base plate is fitted in their place using the same mounting screw. The magnet ring slides onto the distributor shaft in the appropriate orientation (typically marked on the ring to indicate the correct alignment). The two wires from the Accuspark unit connect to the coil terminals, one to the positive supply (which was previously the ignition feed to the original points), and one to the negative coil terminal (the trigger line).
The original points wire from the coil to the distributor is no longer used and can be left disconnected or removed. After installation, the engine timing is set with a strobe timing light using the standard procedure.
Application Coverage
Accuspark kits are stocked for the principal Lucas distributors used across classic-MG production, the 25D pattern fitted to early cars, the 45D pattern fitted to most rubber-bumper applications, and the various other Lucas distributor types fitted across the MGB, MGA, MGC, Midget and MGB GT V8 production years. Each kit is matched to the specific distributor pattern at the point of order, with the appropriate base plate and magnet ring for that distributor. Negative-earth and (rare) positive-earth applications are both covered, with the appropriate wiring polarity for each. The wider 6-cylinder kits (for the MGC C-Series engine) use a six-pulse-per-revolution magnet ring matched to the six-cylinder firing order; the V8 kits (for the MGB GT V8 Rover V8) use an eight-pulse-per-revolution ring matched to the V8 firing order.
The technical team is available to advise on the right Accuspark specification for a specific car.