1968 Pontiac GTO

Before and after dynamometer tests were performed on a 1968 Pontiac GTO, with a 400 C.I. engine.

Horsepower and torque increased immediately upon adding the MPG+. Horsepower went from 195.6 to 205.3, a 9.7 hp gain or 4.96% increase. Peak torque went from 268.5 to 281.4, a 12.9 pound-feet gain or 4.8% increase.  It must be noted that the initial tests were made in December and the tests at 200 miles were made in June, 6 months AFTER the initial tests.  The significance of this fact is that the power of a car is greater in cold weather, because the air is denser, which means that the engine gets more oxygen. Therefore, the horsepower and torque the car is developing is actually GREATER than the test results show. The engine is actually continuing to increase in power, the longer the MPG+ remains in the engine.  A mileage test was performed on the GTO when it had MPG+ in the engine for only 50 miles and it got 8% better fuel economy. The fuel economy and power have increased since initial installation, but we have not been able to remeasure the gain. Ultimately, an engine will reach peak performance and remain there, while MPG+ is in the crankcase.