Boosting the power and efficiency of your Mack E7 engine is a top priority for many owner-operators. This article delves into proven performance upgrades for the electronic E7 Mack, exploring modifications that can significantly enhance horsepower and fuel economy.
Pittsburgh Power’s Performance Computer for the E7
Pittsburgh Power is developing a performance computer specifically designed for the electronic E7 Mack engine. Initial testing shows promising results, with an 80 hp increase at the rear wheels. However, the company is committed to achieving at least a 160 hp gain before releasing the computer to the public. This dedication to rigorous testing ensures a reliable and impactful product for Mack E7 owners.
Simple Changes, Significant Gains: Exhaust System Optimization
Beyond the performance computer, seemingly minor adjustments to the exhaust system can yield substantial fuel efficiency improvements. A test Mack, initially averaging 6.0 to 6.2 mpg, saw a jump to 6.7 mpg after two key modifications:
- Replacing the restrictive muffler with a straight-through performance muffler: This simple swap allows for freer exhaust flow, reducing back pressure and improving engine efficiency.
- Eliminating 90-degree elbows in the exhaust system: By removing unnecessary bends and installing a weed burner system, exhaust gases can escape more efficiently, further boosting fuel economy. This modification involved removing the dual stacks behind the bunk and installing a 4-foot chrome pipe underneath the truck, dumping exhaust before the differential.
These changes demonstrate that significant gains can be achieved with relatively inexpensive modifications, costing only around $158 for the muffler and a salvaged chrome stack.
Further Enhancements: Under the Hood
Future performance upgrades for the Mack E7 will focus on under-the-hood modifications. These include:
- Installing a ported and Jet Hot coated exhaust manifold: This upgrade further reduces exhaust restriction and heat, optimizing engine performance. The Jet Hot coating provides thermal insulation, keeping exhaust gases hotter for improved flow and potentially increased turbocharger efficiency.
- Adding a FASS fuel system: Upgrading the fuel system ensures a consistent and reliable supply of fuel to the engine, crucial for maximizing power output and efficiency. A FASS system can help prevent fuel starvation and maintain optimal fuel pressure under demanding conditions.
Exploring Turbocharger Upgrades
Given the relatively small size of the turbochargers on Mack E7 engines, investigating the potential benefits of a larger turbo is warranted. Back pressure checks in the exhaust manifold will help determine if a larger turbocharger is necessary. This upgrade could significantly increase airflow into the engine, leading to a substantial horsepower boost.
Thinking Outside the Box: Gearing and Tires
Further possibilities for enhancing the Mack E7’s performance include gearing the truck to run in direct drive, converting it to a single axle with a liftable pusher axle, and using super single tires. These modifications, often seen in glider kits, aim to minimize drivetrain losses and maximize fuel economy. The goal is to achieve fuel efficiency in the 9 mpg range, similar to results seen with Signature Series glider kits.
Addressing Concerns About Power Increases
A common concern among owner-operators is the potential for damaging their trucks with performance upgrades. However, it’s important to remember that it’s the driver, not the inherent power of the truck, that causes damage. Modern trucks are built to withstand significant stress. By monitoring the turbo boost gauge and pyrometer, avoiding lugging the engine on hard pulls, and driving responsibly, owner-operators can safely enjoy the benefits of increased horsepower and torque without risking damage to their equipment.
Conclusion
Optimizing the Mack E7’s performance involves a multifaceted approach, ranging from simple exhaust modifications to more complex engine and drivetrain upgrades. By carefully implementing these enhancements and practicing responsible driving habits, owner-operators can unlock the full potential of their Mack E7 engines, achieving both impressive power gains and significant fuel economy improvements. Ongoing research and development, like Pittsburgh Power’s performance computer project, promise even greater potential for the Mack E7 in the future.
