When the ignition system on Project Street Reaper needed an upgrade, the MSD Pro-Billet Ignition Bundle was the clear call. This 1976 Camaro is running a built small block 350 bored .040 over, a Summit Racing cam with .519/.542 lift, AFR Enforcer heads, and an ATM Innovations carburetor. The combo makes real power, but it had a weak link sitting right on top of the engine.

The distributor was a stock-style AC Delco unit with unknown mileage and unknown age, and frankly, it looked clunky and out of place on an otherwise serious build. A hot rod with AFR heads and a performance cam deserves better than a mystery distributor from an unknown era. The build had a solid foundation and bringing the car into the 21st century with an MSD Pro-Billet Bundle (P/N 85551K) was the move, and the install turned out to be one of the smoothest installs.

Shop MSD Pro-Billet Bundle for Chevy small-block here.

Shop MSD Pro-Billet Bundle for Ford small-block here.

The bundle includes an MSD Ultra 6AL Ignition Control (P/N 6423), an MSD Pro-Billet Distributor (P/N 85551), and an MSD Blaster 2 Ignition Coil (P/N 8202) and all the components are made in-house at MSD's El Paso, Texas HQ. The only add-on needed for this particular build was an ignition coil mount (P/N 8213), because the previous distributor had the coil built into the cap. If you are already running an external coil, that purchase can be skipped. Bundling these pieces together saves up to $140 compared to buying each component separately, and the kit even includes MSD Harmonic Balancer Timing Tape for setting your marks.

Why a Stronger Spark Actually Matters

Before getting into the install itself, it is worth talking about why ignition strength matters on a built engine in the first place, because it’s an important concept that often gets overlooked.

A stock ignition system was designed to reliably fire stock plugs in a stock engine running pump gas in a world where fuel formulas were different. That world does not exist anymore. Today's pump gas, particularly ethanol-blended fuels like E10 and the increasingly common E15, has different combustion characteristics than the leaded and early unleaded fuels these engines were originally tuned around. Ethanol-blended fuels require a more complete burn to extract their energy efficiently, and a weak spark struggles to fully ignite the mixture, especially under load or at higher RPM, where dwell time gets compressed.

The challenge compounds on a built engine. Bigger camshafts increase cylinder pressure overlap, hotter compression ratios tighten the margin to realize complete combustion, and performance cylinder heads like the AFR Enforcers on this build flow significantly more air and fuel than factory iron heads. More air and fuel in the cylinder means more demand on the spark to light it all off reliably and completely. A weak or inconsistent spark leaves unburned fuel in the cylinder, which translates directly to lost power, fouled plugs, and an engine that never quite runs as clean as the parts inside it deserve.

A stronger spark, like the 150 millijoules the MSD Ultra 6AL produces, ignites the air/fuel mixture faster and more completely across the entire RPM range. That means cleaner combustion, better throttle response, and power that actually reflects what the cam and heads are capable of. It also means wider plug gaps can be run, which exposes more of the mixture to the initial flame kernel and helps combustion efficiency even further. On a performance build running modern pump gas, a performance ignition upgrade is one of the more direct paths to getting the most out of everything else already in the engine.

The day before the actual install, we sat down and read the 6AL Ultra manual cover to cover. This is something more builders should do, and it paid off immediately. Page 12 of the 6AL Ultra instructions specifically addresses whether the centrifugal advance needs to be locked out. The answer is that it only needs to be locked out if the box is being used to control timing advance beyond 10 degrees. Since we were running this setup strictly as an ignition amplifier and not using it to manage timing tables, the centrifugal advance was fine to leave alone.

With that cleared up, attention shifted to the timing curve. Knowing that this SBC 350 build is likely making peak torque somewhere in the mid-4,000 RPM range, the goal was to have peak timing land right around 4k. The factory spring combination out of the box provided a solid ramp toward that target. A common swap is one heavy spring and one light spring, but that pushes peak timing closer to 4,700 RPM. Running two light springs would pull peak timing back to the mid-3,000 RPM range, which might be worth revisiting later. For now, the stock springs hit the sweet spot, so we left them exactly as they came.

Installing the MSD Pro-Billet Distributor

With the engine rotated to top dead center, the old AC Delco cap came off, and we noted where the rotor was pointing. Using the intake manifold bolts as reference points is a reliable method. The rotor was pointing at the third bolt in on the driver's side, which is exactly where it landed during the cam swap. When the MSD Pro-Billet distributor went in, it was aimed at that same third bolt.

The Pro-Billet unit is machined from 6061-T6 aluminum and hand-crafted in El Paso, Texas. It removes the vacuum advance canister entirely, which frees up a noticeable amount of real estate in the engine bay. That room came in handy for mounting the Blaster 2 coil nearby without cramming anything in.

One thing worth noting about the oil pump engagement: a lot of forum posts suggest using a long flat-head screwdriver to align the oil pump shaft before dropping the distributor in. A cleaner method is to drop the distributor in as far as it will go; there will be about 1/8 of an inch of stickup, then apply slight downward pressure while rotating the engine by hand until the distributor seats fully. Tighten the clamp just enough that it holds position but can still be rotated by hand. That way, timing adjustments can be made later in the process without any headaches.

Mounting and Wiring the MSD 6AL Ultra

The MSD Ultra 6AL is the next generation of MSD's 6 Series ignition. It delivers up to 150 millijoules of spark energy, which is a meaningful step up over the Digital 6AL, and it comes in a smaller, lighter package. The box also features Bluetooth connectivity, which changes how rev limiters get managed in a real way.

Shop Chevy SBC Pro-Billet Bundles here.

For placement, the driver's side fender was chosen. There were easier spots available, but that location kept the labeling on the box readable and pointed the wires in the right direction. The included standoffs were used for mounting. These have a rubber lining that absorbs vibration, which matters on a car with 20-year-old suspension that rattles harder than it should. The standoffs also create an air gap under the box to keep operating temperatures down.

Wiring this setup as a straight ignition amplifier only requires six wires and one plug-in connector. The distributor comes with a plug-in harness that connects directly to the ignition box on one end and the distributor on the other. The orange and black wires feed the ignition coil. A slim red wire taps into a 12-volt ignition-on source, in this case, the red wire from the old distributor plug. The gray wire goes to the tach output, which was the green wire off the old distributor plug. The heavier red and black wires run straight to the battery terminals.

Any wire routed near a heat source is wrapped in heat-proof insulation. It is the kind of detail that gets overlooked but saves a real headache when a melted wire takes down an ignition system at the worst possible moment. The 6AL Ultra also has wiring provisions for an MSD Power Grid, which would enable a Step Retard, Burnout Rev Limiter, and Two-Step. Those features are not being used yet, so those wires were cut with enough length for future use and capped with clear heat shrink tubing.

Gapping Plugs and First Fire

A stronger spark means the plug gap needs to open up. Per the MSD instructions for this engine combination, the target gap range was .050 to .060 inches. The existing plugs were sitting at .040, so new plugs went in across the board. A fresh set of AC Delco 3924s was gapped to .050 and installed.

With everything buttoned up, the key went to accessory mode, and the box lit up orange, confirming power with the engine off. The MSD Ultra 6AL app was pulled up on the phone, available on both iOS and Android. V8 mode was selected, and the rev limiter was set conservatively at 3,000 RPM just to confirm everything was reading correctly before firing the engine. The app showed RPM climbing during cranking, so the box was picking up a signal from the distributor.

After the typical carbureted car dance of a few throttle blips, the engine fired. A timing light confirmed 12 degrees of base timing, right in the 12-to-16-degree sweet spot for an SBC. With the engine warmed up, total timing with advance came in at 34 degrees. Since the camshaft has not been degreed, keeping total timing at 34 instead of pushing to 36 was the smart play. If the cam is off by a degree or two and timing gets bumped to 36, actual advance could end up closer to 38, and that is territory where detonation becomes a real concern.

Timing by ear backed up the numbers. At 12 degrees base and 34 degrees total, the engine sounded and felt exactly where it wanted to be. Throttle response was a chef's kiss.

Honest Mistakes: The Bang Heard Round the Garage

In the spirit of full transparency, there was a moment during the first startup that aged me about five years in under a second. In the process of trying to coax the engine to life, the throttle got pumped one too many times. Then another. Then a couple more for good measure. Classic carb cranking impatience. Gas ran down into the exhaust, and when the engine finally fired, what followed was the single loudest bang this garage and car have ever produced. The unburned gas sitting in the muffler ignited, and the whole thing went off like a gunshot.

It has been years since a car genuinely startled me like that, and it was entirely self-inflicted. Do not over-pump the carb during cranking. A couple of blips to prime the accelerator pump is all a carburetor needs. After that, crank and let the fuel do its job.

The Bottom Line

MSD has been building performance ignition systems for over 50 years, and the Pro-Billet Bundle is the product of that experience brought forward into a modern package. Bluetooth rev limiter adjustments from a phone app, 150mJ of spark energy, a distributor machined in the USA, and wiring that does not require an electrical engineering degree make this one of the more approachable ignition upgrades available for a hot rod, street car, or drag car. The install on Project Street Reaper went smoother than expected, and the car responded to it immediately. The MSD stickers are now applied, and we all know that is where the real horsepower lives.

About The Author: Caecey Killian is the driving force behind Car Junkie Mag, where the builds are personal, the knowledge is earned, and the goal has always been the same: inspire the next generation of gearheads to get their hands dirty and start something of their own. Check it out here.