We already know the Ford Focus RS is one hot hatch in stock form. But as enthusiasts begin to go beyond the bolt-on upgrades and dig into the EcoBoost engines internals, we are starting to see just how much power this 2.3-liter EcoBoost engine can handle.

Earlier this month, Adam Brunson, CEO and founder of Tune+ Performance Calibrations near Dallas, Texas, surpassed the 600 wheel horsepower mark on a Ford Focus RS. He delivered this RS acheivement using a Tune+-built crate engine and a massive turbo upgrade using the Extreme Turbo Systems twin-scroll GTX3582R-2 turbo from Honeywell Garrett.

“Final numbers were 632 wheel horsepower and 520 wheel torque. We finished tuning around midnight tonight and were fighting the stock low side fuel pump, too soft of springs in the wastegates, and having just enough injector on the port side,” said Adam on social media. “You can see the dips on the graph from the gate oscillating trying to control boost. Drop in some higher pressure springs, and it would smooth right out.”

According to Adam, he only had one night to perform the in-house tune and dyno on this particular Focus RS, and the customer was shooting for a goal of 600 wheel horsepower.

“The turbo is a little big for this engine, so I made the power as linear as possible. It feels awesome on the street and just keeps pulling and pulling,” he added. “However never peaking out makes it a unique driving experience. We both really liked how it drove on the street.”

For future builds Adam plans on sticking with the Garrett GTX3076R-2 or testing with the new Precision Turbo in open scroll.

Because some of the issues that Focus RS owners have reported when upgrading the stock RS 2.3-liter engines, it’s important to point out that TUNE+ Focus RS engines are built with 2.0-liter blocks and use the 2.3-liter internals. These crate engine do not require cylinder support systems and have been tested to 650 wheel horsepower.

The above dyno sheet is some exciting news for RS owners looking at upgrading to a larger turbo. With the announcement of the new G0Series small-displacement turbo from Honeywell Garrett and Turbonetics new 60mm Ford Focus RS drop-in turbo upgrade that both debuted at this years SEMA Show in Las Vegas, we expect to see more big power builds from tuners early next year.