MSD makes a high-end, high-performance distributor for almost every modern engine still in use, be it an off-roader, a hot rod, or a stocker; if it uses a distributor. Using a Chevy V8—arguably the most popular conversion engine in use today—as the example, we pulled the OEM distributor and installed an MSD unit with selectable vacuum advance to show how it’s done.
This particular engine had a history of overheating and pinging under high-RPM loads—a common plight for engine conversions—so we were trying different solutions. We’d gone back to a mechanical, high-flow fan and custom-made radiator fan shroud, which pretty much cured the high-speed heating problem, but the engine was still pinging on long freeway hill climbs. Because it didn’t ping around town or on the trails, we decided that the OEM distributor—even though it was timed correctly at idle—was advancing the ignition too far at higher RPM on the freeways.
The OEM General Motors distributor does not have a selectable vacuum advance degree, whereas the MSD distributor (PN MSD8362; $150) does. And we included MSD ignition cables (PN MSD31229; $86) to avoid future problems with the old OEM spark plug wires. Known as the Street Fire HEI (high energy ignition) distributor, its components offer a well-designed product that also has a one-year warranty. Knowing the importance of a centrifugal advance in a distributor, we wanted the Street Fire because it has an advance assembly with coated weights and welded weight pins (not just pressed in like other models). Plus the Street Fire has the same drive gear that is used on MSD’s Pro-Billet models. The metallurgy of this gear has been refined for years to perform through the harshest conditions.
Inside the distributor, the ignition module and coil work together to produce a high-energy spark to light the fuel mixture. The high voltage is transferred through a new rotor to the brass terminals of the distributor’s cap and out to the plugs. The Street Fire distributor has an adjustable vacuum advance that helps tune it to each individual engine, with a mechanical and selectable advance up to 21 degrees.
As mentioned earlier, we included an MSD 8.5mm Super Conductor wire set, which has a special helically wound core that has just 40-50 ohms of resistance per foot—but with an RFI suppression equal to a 1,500-ohm wire. In fact, each foot of finished wire features 40 feet of tightly wound copper for superior conductivity. A tough, 8.5mm synthetic/silicone jacket over an extra-heavy glass braid and dielectric insulator keeps the current guided to the plugs. Underneath the high-temperature boots, dual crimp stainless steel terminals feature snap-locks to ensure a secure fit. MSD’s 8.5mm Super Conductor wire sets come available in custom or universal-fit applications.