With a turbo upgrade, Lethal Performance’s 2.3-liter puts down over 425 hp
By Steve Turner
Photos by Steve Turner and courtesy of Lethal Performance
If you’ve been following the saga of Lethal Performance’s EcoBoost Mustang project here on the Front Page, you know the company has been taking a steadier—dare we say, more sensible—approach to building up its turbocharged four-banger. We kid, of course, because Lethal always starts with the basic bolt-ons just like its customers would, but its V-8 projects have tended to jump straight from mild directly to wild.
In this case, that steady approach has made for an informative series of stories. In the first installment, we covered the traditional bolt-ons, including a JLT cold-air intake, a Lethal high-flow downpipe, and a custom calibration from Lund Racing. The results were quite good, but as we have found heat-soaking is the next hurdle to over come when you are ramping up an EcoBoost-powered Ford. As such, the Lethal team worked with RareFab in developing an intercooler upgrade for the 2015 and newer 2.3 Mustangs. With revised tuning and the intercooler in place, the car definitely picked up some power.
So that brings us back to Power by the Hour in Boynton Beach, Florida, to document the testing of the latest collaboration from Lethal Performance and RareFab—a turbocharger upgrade kit. But first, we stopped by Rarefab to see the kit installed.
“I’ve known Will at Rarefab for a while now and have seen plenty of his work. He’s a true enthusiast and is very, I mean very good at what he does,” Jared Rosen of Lethal Performance said. “That’s exactly why we chose him to do our turbo kit. Just take a peek at the downpipe he made for the car. That should be enough for anyone to see the level of quality this kit holds.”
The resulting kit allows for an easy, bolt-on installation of a larger Borg-Warner EFR 7163 turbo, and it is fully compatible with the Lethal/Rarefab intercooler that’s already on the car.
“We always strive to deliver the best in quality and performance so it was very easy to go with the Borg Warner EFR series turbo. They have unsurpassed build quality with an amazing amount of built in features giving them great performance in one bolt-on package,” Will Barnette of RareFab in Boynton Beach, Florida, explained. “The EFR series are available with a built-in 50mm wastegate that saves the cost of designing and fabricating a wastegate into the manifold. This turbo also comes with a built-in recirculation valve, a water-cooled center housing, robust ceramic-ball-bearings, and even a port for compressor wheel speed sensor. So after finding the right product for our setup it was just a matter of figuring out the correct sizing to maximize power and quick spooling.”
Combined with a new custom calibration the results of this bolt-on kit are pretty impressive. It boosted the peak output of the Lethal EcoBoost Mustang by over 100 horsepower and 57 lb-ft of torque. One facet of that new calibration makes the idle behave like the 2.3 is equipped with the choppier aftermarket camshaft. You can listen to it right here…
“We were all very impressed with the results we got with this kit. To up the power by 200-plus rear-wheel horsepower over stock with a bolt-on turbo upgrade is fantastic,” Jared said. “The car drives just like it did before. Super smooth and wicked easy to drive around town. However once you get into that throttle it’s an entirely different car. That turbo sound is much more noticeable and the car just keeps on pulling to redline.”
As you might imagine, the arc of this build is about to take a turn from the gradual to the more aggressive. So far the Lethal EcoBoost Mustang has run an 11.85 at 115.20 mph with hot shoe Jeremy Martorella banging gears. To prep it for the drag strip the company also added a lot of drivetrain and suspension upgrades. Stay tuned, as we’ll cover the installation of that gear in the near future. Likewise, the future surely holds much lower e.t.’s for this giant slayer.
“Our next step is going to be a piggyback fuel system as we believe the direct injection is the biggest challenge we have in supporting big power,” Jared added. “The fuel system will consist of the CP-E secondary fuel rail, fuel cell with fuel pump, additional fuel injectors and an injector-controller box. Once we’ve got the extra fuel behind us we’re gonna turn it up and try to get this six-speed into the 10s.”