The Ford Explorer isn’t typically associated with speed, even with its ST badging, as it’s more often seen at school pickups or soccer games than on the dragstrip. However, with advancements in direct injection, turbo technology, and fast-shifting transmissions, transforming this family SUV into a 10-second performer is now easier than ever. What once required a two-page build sheet can now be achieved with a few key upgrades, proving that the Explorer ST has serious performance potential.

Most EcoBoost-centric shops, product manufacturers, and racers recommend an intercooler, intake, upgraded turbochargers, larger fuel system, tuning, and a built transmission to handle the increased power levels. Below, you’ll find the recipe to turn “the wife’s Explorer” into a sleeper SUV. 

One of the first builds to really propel the Explorer ST platform into the 10-second range was owned by Kevin Krupski.

Keeping IAT’s Down

It’s no myth that internal combustion engines perform better with cold air entering the intake manifold. However, when turbochargers utilize recycled hot exhaust gasses to spin the turbine and force air into the intake, air temperatures naturally rise. This is where the intercooler steps in, cooling the hot air before it enters the manifold.

Unfortunately for Explorer ST owners, Ford equipped it with an undersized intercooler from a performance standpoint. This causes what is known as “heat soak,” where rising intake temperatures force the ECU to cut back on boost and spark timing, leading to reduced performance.

The Whipple intercooler for the 3.0-liter EcoBoost offers over 200-percent more volume than the stock unit, significantly reducing heat soak — an issue common with factory intercoolers.

To address this, Whipple Superchargers intercooler is noticeably larger and demonstrates a significant improvement in cooling efficiency. As Whipple’s Product Line Director, Nick Purciello, explains, “One of the EcoBoost-powered vehicles we tested was the Ford Explorer ST. We used the manifold charge temperature (MCT) as our comparison metric, as it represents the temperature of the air just before it reaches the combustion chambers.”

Under wide-open throttle with the stock intercooler and tune, the manifold charge temperatures (MCT) start at 150°F at 0 mph and rise to 156°F at 60 mph. By the time the vehicle reaches the ¼-mile mark, the MCT can reach as high as 170°F. As Purciello explains, “At the temperatures above, the PCM will reduce boost and spark advance to protect the engine.” This variability in stock intercooler performance can lead to a loss of power in extreme conditions, making peak engine performance inconsistent from run to run due to heat soak.

In contrast, the Whipple intercooler significantly lowers MCT readings. At 0 mph, the MCT is just 100°F, and it drops to 85°F at 60 mph. “At these temperatures, there will be no limiting of boost or spark,” Purciello states. “Even at the quarter-mile, we do not see manifold charge temperatures stray too far from ambient conditions. Performance will be much more consistent as there is no heat soak, and temperatures drop rapidly and stay down once you are moving.” This improved cooling efficiency helps maintain optimal performance, even under demanding driving conditions.

Uncorking The Intake

While the intercooler is known to be undersized and not able to dissipate heat, the air intake system does not fare much better. The paper factory filter does not provide the same amount of air filter surface area as an aftermarket dual cone unit or provide an enlarged piping to help facilitate the air passing through.

The aFe POWER Momentum GT cold air intake system replaces the stock airbox and paper filter. This comprehensive replacement features a larger airbox with two 6-inch cone filters, increasing airflow from the stock 295 cfm to 375 cfm. The Momentum GT air intake system also includes intake piping designed to enhance airflow from the intake box to the turbos. While the factory design is functional, it limits performance. In turbo applications, more air translates to better performance, making the intake system a crucial component for maximizing the Explorer ST’s capabilities. 

Fueling For Days

To unlock more horsepower, upgrading the factory injectors in your Explorer ST is crucial. Nostrum’s Stage 3 injectors offer a 96-percent increase in fuel flow compared to stock injectors. These Stage 3 injectors allow you to lower commanded pressure from 24 MPa to 20 MPa, resulting in a 5-percent increase in flow from the high-pressure fuel pump (HPFP). This additional fuel flow translates directly into more horsepower and torque, making these injectors an essential upgrade for high-performance builds, especially when aiming to avoid fuel starvation at higher RPM.

The Nostrum Stage 3 injectors for the 3.0L EcoBoost Explorer ST offer 96% more fuel flow, perfect for built engines and larger turbos.

Unlike other fuel delivery solutions, such as methanol injection systems that require extra controllers, tanks, and injectors, Nostrum’s Stage 3 injectors integrate seamlessly with the Explorer ST’s factory ECU. 

Nostrum also offers an HPFP upgrade kit, which delivers 47-percent more fuel than the factory pumps. This additional fuel supply is critical for maintaining torque at lower RPM and achieving maximum peak horsepower at higher RPM. Proper tuning is vital to fully exploit these upgrades, and with the right setup, you’ll be positioned to break new performance records.

Upgrading Factory Turbochargers

Currently, bolt-on aftermarket turbochargers for the Ford Explorer ST are limited, making a factory turbocharger upgrade the go-to solution for making more power. The CR Performance Stage 5 46mm Upgrade Twin Turbocharger Set is the ultimate choice for those aiming to support over 600 all-wheel horsepower (AWHP) on E85 fuel.

This turbo kit offers direct fitment, seamlessly dropping into the stock turbo locations of the Explorer ST without requiring custom modifications. With the Stage 5 upgrade installed, you can expect impressive power gains: over 560 AWHP on 93-octane fuel, 590 AWHP on E50, and a staggering 600+ AWHP on E85. With these power levels, achieving a 10-second quarter-mile time becomes entirely possible.

The Stage 5 turbos are equipped with high-performance 6+6 blade 46mm/56mm CR billet compressor wheels, which significantly improve airflow and power output. These are paired with a 50mm MAR CR 8-blade turbine that not only ensures rapid spool times but also provides durability under the most extreme driving conditions. The turbos are engineered from brand-new OEM Ford turbochargers, undergoing in-house CNC machining and digital assembly balancing to deliver a flawless blend of factory reliability and aftermarket performance.

Tuning Into Performance

Tuning is essential for optimizing the Ford Explorer ST’s performance. As ZFG Racing owner Adam Staszak explains, “Tuning is everything. Without tuning, the factory ECU wouldn’t be able to optimize the additional aftermarket parts.” This highlights the importance of adjusting the engine’s parameters—such as fuel maps, ignition timing, and boost levels—to ensure the vehicle operates at its peak potential.

With the Explorer ST’s 3.0-liter EcoBoost engine capable of producing over 600 horsepower, a well-executed tune is crucial for effectively harnessing that power. “It’s not just about adding horsepower; it’s about maintaining OEM-like drivability while improving on some OEM shortcomings,” Staszak says. “The factory ECU, with the help of some custom HP Tuners code, allows us to dial the tune specific to each drive mode available in the car. I like my tunes to feel stock and unsuspecting in Normal mode—until you hit the gas! In other drive modes like Sport mode, you get to feel the full aggression of a well-dialed-in 10-speed transmission and almost double the stock HP. There’s an art to creating the best all-around tune.”

Transmission tuning is equally important for the Explorer ST, especially with the 10R60 transmission. Custom tuning can optimize shift points and firmness, allowing for faster shifts without sacrificing comfort. Staszak notes, “A properly tuned transmission allows for faster shifts while reducing wear and tear on the clutches at higher torque levels. With the 10R60 having less torque capacity than its big brother, the 10R80, torque management is key. Producing an engine tune that maintains a nice flat torque curve by ramping in the boost is a crucial factor in keeping these transmissions alive.”

Corey Ruzzin’s Explorer ST delivers an impressive 601 AWHP on pump E85, thanks to the Nostrum High Performance Stage 2 injectors, which are 24-percent larger. His build includes a ZFG E85 tune, Stage 5 CRP turbos, Nostrum HPFP and Stage 2 injectors, NGK spark plugs, an aFe intake, CVF intercooler, SPD downpipes, Lethal 2.5-inch mid-pipe, Borla S-Type cat-back exhaust, and FenFab charge pipe with a blow-off valve.

Transmitting The Power

With the engine’s now capable of exceeding 600-plus horsepower, you’ll need a transmission that can handle the output. Although the 10R80 gets most of Ford’s notoriety, the 10R60 found in the Explorer ST is slightly different. The 10R60, with its 7.39 gear ratio spread and a low First gear of 4.70, allows the Explorer ST to launch off the line while maintaining engine RPM. Each shift results in a minimal RPM drop of approximately 20-percent, which helps keep the engine in its peak performance range efficiently. However, to achieve a goal of running a 10-second quarter mile, you’ll need to beef up the transmission to handle the increased power.

For that, Suncoast Performance offers an upgraded rebuild kit specifically designed for the 10R60 transmission. This comprehensive kit includes Raybestos Powertrain GPZ friction plates, which significantly enhance transmission performance and durability. These state-of-the-art friction materials exceed original equipment (OE) specifications, providing up to a 20-percent increase in performance. They are designed to withstand high stress, high temperatures, and repeated cycling, making them ideal for heavy-duty applications and spirited driving.

Montana Cherry from Suncoast Performance emphasizes the importance of addressing the factory limitations of the 10R60: “The 10R60 suffers from only having three ‘F’ clutches [from the] factory. We combat that by going to the more aggressive friction material and also increasing that capacity to a 4-clutch design, much like the 10R80.” This strategic upgrade allows for better handling of higher horsepower applications, making the transmission more reliable under demanding conditions.

The Suncoast rebuild kit also includes an upgraded fluid pump and valve body designed to optimize lubrication and ensure the clutches and converter receive maximum line pressure. Cherry highlights this enhancement, stating, “We supply the clutches and converter with maximum optimal line pressure, enhanced lube circuit, and 40-percent more lockup apply oil. This results in less wear and faster clutch apply times” 

Another critical aspect of the rebuild kit is the expanded capacity E clutch drum, which is fully assembled and machined for enhanced oiling. This improvement increases the clutch stack from a factory 4-clutch setup to a robust 5-clutch design, providing greater capacity and reliability in high-demand situations. The clutch kit also includes options for adding clutches to the F clutch pack, addressing one of the more vulnerable areas in the 10R60 design.

Proven Performance

Factors such as driver skill, vehicle condition, and tire choice will still play essential roles, the combination of top-tier components creates a winning formula for turning the Explorer ST into a 10-second powerhouse that will surprise not only you but also the competition. The Explorer ST and EcoBoost community is a close-knit group, and they have access to some incredible options. For those serious about speed, ZFG Racing offers a complete performance package, which includes the ZFG Racing tune, Nostrum fuel system, and CR Performance turbocharger upgrades, all designed to push the limits of the Explorer ST.

For maximizing airflow and cooling, aFe provies highly efficient air intake systems and Whipple has a front-mount intercooler to keep those intake temperatures down. Meanwhile, Suncoast Performance can build a custom transmission tailored to your needs, ensuring that all that extra horsepower is delivered smoothly and reliably.

With these carefully selected upgrades, the 3.0-liter EcoBoost engine in the Explorer ST is ready to take on the quarter-mile and leave a lasting impression on both spectators and competitors. It’s clear that Ford’s twin-turbocharged V6 engine has a knack for surprising speed, and we can’t wait to see more Explorer STs proving their dominance on the strip.

Photo credit: Marc Seery Photography