Brain Power

More power and better efficiency can be had by “re-flashing” your engine’s ECM.

Brain Power

Engines like these Mercury Racing sterndrives are popular candidates for “flashing.”

With gas at $4/gallon or thereabouts and the economy still struggling to bounce back, go-fast enthusiasts are spending smarter, especially when it comes to upgrades. For example at Whipple Industries, which makes some of the most popular supercharger kits for marine performance applications, customers aren’t knocking down the doors for blower kits, which can cost a minimum of $5,000.

They are, however, sending in their Electronic Control Modules (ECMs) for their engines to have them re-programmed or “flashed”, as it is commonly called, to boost performance.

“Supercharger sales have declined because of the economy,” said Dustin Whipple, marketing and marine program manager for Whipple Industries. “But I’ve got more than 27 ECMs sitting here.”

The most popular engine for re-flashing is the Mercury Racing HP525EFI. Send your engine's ECM to Whipple and after a $995 re-flash, you'll see approximately 25 more hp and 30 foot-pounds of torque, according to Dustin Whipple. If you want to upgrade a MerCruiser 350 MAG MPI, you'll spend about $600 for a 20 hp gain. Re-programming an ECM also improves fuel economy.

Whipple explained that people will re-build an HP525EFI, turning it into a 540-cid block over the stock 502-cid configuration and then have the ECM re-configured to help the motor build the horsepower to match the increased bore and stroke.

If you own a Mercury Racing engine up to the HP1200 SCi, the upgrade kit includes a supercharger and ECM modification that will provide significant gains in power and torque. For example, a Stage 1 Whipple kit for the HP700 SCi retails for $2,095.95 and includes a computer recalibration that increases the maximum power by more than 90HP and 90 pounds of torque. Whipple also increases the low rpm power range and bumps the factory rpm limiter to 6000 rpm compared to the stock rating of 5400 rpm. The engine requires 91-octane gasoline. Bump up to Stage 2 for $2,895 and you increase the power by coupling a Stage 2 performance calibration with a Whipple stage 2 supercharger pulley. The Whipple Stage 2 system also includes a bolt-on water system upgrade to increase system pressure and intercooler efficiency. This system helps boost the engine’s output by more than 140 hp and 120 foot-pounds of torque, depending on the application. Whipple also increases the low rpm power range and raises the rev limiter to 6000 rpm.

Whipple also has kits available for carbureted Mercury Racing engines including the 502-cid HP500 and the 540-cid HP500 Bulldog and soon will have ECM upgrades for Mercury Verado outboards. After Whipple works its magic, a 300-hp Verado will reportedly make 340 hp. For more information, check out