Developed for the classic race and rally scene, CSI is the Dutch manufacturer producing the Magnetronic range of solid-state electronic distributors for classic British cars. The CSI distributor is a complete replacement for the original Lucas-style distributor, not a conversion of the existing distributor, but a fundamentally new unit that fits into the existing engine mounting in place of the original. The result is a distributor with no mechanical advance mechanism, no points, no condenser, and no wear surfaces of any kind, purely electronic operation across the working life of the unit.
How the CSI Distributor Works
The CSI Magnetronic distributor uses a Hall-effect trigger inside the distributor body, detecting the position of a multi-pole magnetic ring carried on the distributor shaft. The shaft is driven by the engine in the same way as the original Lucas distributor (typically through a skew gear on the camshaft), and the rotor arm carried at the top of the shaft distributes the spark to the cap segments in the conventional manner. The electronic-advance circuit inside the distributor body controls the timing curve, the relationship between engine speed and ignition advance, with preset specifications matched to the standard engine applications. For an MGB, the curve matches the original Lucas specification for a standard B-Series engine. For a Midget, the curve matches the A-Series specification.
The matched specifications eliminate the need for owner setup of the advance curve.
What the Preset Curves Provide
The advance curve on a CSI distributor is set during manufacture rather than being programmable by the owner. The curves are matched to the original Lucas specifications for the standard engine applications, with appropriate variations for different engine variants (chrome-bumper vs rubber-bumper MGB, MGB vs MGB GT V8, the various Midget specifications, and so on). The preset approach is appropriate for owners running standard or lightly-modified engines where the original advance curve is the right specification.
For owners running heavily-modified engines that need a custom curve, the programmable 123ignition alternative (covered in its own sub-section) is typically the appropriate choice. The CSI's preset curves provide consistent, reliable operation without owner setup beyond the initial timing adjustment.
Installation and Long-Term Reliability
CSI distributor installation involves removing the original Lucas distributor from the engine, fitting the CSI unit in its place, connecting the wiring to the existing coil terminals, fitting the appropriate cap and rotor arm (typically supplied as part of the kit), and setting the initial timing with a strobe timing light. The installation is straightforward for any owner familiar with the original distributor, the mounting, the drive arrangement, and the cap-to-spark-plug-lead routing are all unchanged from the original. The long-term reliability is dramatically better than the original Lucas distributor, no points to wear, no condenser to fail, no advance mechanism to seize or break. The CSI unit typically delivers many years of trouble-free operation across the working life of the conversion.
The technical team is available to advise on the right CSI specification for a specific car.