Shaving Two Tenths for Under $75: Tuning the Dura-spark Ignition
In bracket racing, dropping two-tenths of a second off your elapsed time usually requires pulling weight, dropping serious cash on engine internals, or swapping to a stickier tire.
But between our last couple of track outings, I managed to shave our ET down from a 12.99 to a 12.79 using nothing but basic hand tools, a couple hours in the shop, and less than $75 in parts.
If your car is running a classic Ford Duraspark ignition setup, you are likely leaving free ET on the table. Here is how we woke the combination up.
The Recipe: Hotter Spark and Quicker Advance
When we built this motor, we kept the ignition simple and reliable. But factory stock ignition curves are engineered for gas mileage and emissions on the street, not for turning on win lights at the dragstrip.
We attacked the ignition system from two angles:
1. Ditching the Stock Coil ($55)
The factory canister coil does its job, but it tends to tire out and lose spark intensity at higher RPMs. I unbolted the stock unit and swapped it for an MSD Blaster 2 ignition coil.
The mechanical upgrade here is straightforward: a higher voltage output means a hotter, more consistent spark. This ensures a complete, clean burn in the combustion chambers through the traps, eliminating any top-end drop-off.
2. Recurving the Distributor ($15)
This is where the real ET was hidden. Out of the box, a stock Duraspark distributor doesn't bring in full mechanical advance until way up around 4,000 RPM. In a drag racing environment, that means the engine is starving for total timing through the launch and the meat of the powerband.
Using a budget-friendly Mr. Gasket distributor advance spring kit, I swapped the heavy factory springs for lighter ones. Now, the distributor reaches full advance before 3,000 RPM. Bringing that timing in earlier gives the car significantly more punch right out of the hole.
The Bench Work: How It’s Done
You don't need a professional tuning shop to execute these changes. Both modifications are easily tackled on a workbench.
The Coil Swap: This takes five minutes. Loosen the factory retaining clamp, slide the old canister out, drop the new MSD Blaster 2 in, and connect the wiring terminal.
The Spring Swap: Pop the distributor cap and rotor out of the way. Remove the vacuum advance assembly, slide the reluctor up, and unscrew the base plate to expose the factory mechanical advance weights and springs. Hook the new, lighter springs in place, reassemble, and set your baseline timing with a light.
The Results on the Timeslip
The difference on the track was immediate. The engine picked up crisp throttle response right off the line, and the car pulled significantly harder through the first 60 feet. Here is how the numbers shook out:
The Baseline Setup: Stock coil and factory springs. Full advance arrived late at around 4,000 RPM, giving us a 12.99 ET baseline.
The Tuned Setup: MSD Blaster 2 and Mr. Gasket springs. Full advance now hits hard before 3,000 RPM, dropping the ET straight to a 12.79.
You don't always need a high-dollar aftermarket setup or a complex digital control box to see results. Sometimes, just optimizing the analog mechanical systems you already have is enough to put you right where you want to be.
