Part 8: Upgrading The Turbo Without Breaking The Bank
To wrap up Vincent Uriah’s 2003 Ford 7.3L Power Stroke work truck project, we decided to upgrade the turbocharger. Rather than install a high-dollar competition-minded turbo, we wanted something fitting for a real-world work truck built on a real-world budget. After speaking with the pros at Swamp’s Diesel Performance in La Vergne, Tennesee, Uriah decided the best plan was to improve his factory Garrett turbo by upgrading to a billet compressor wheel and removing the exhaust backpressure valve (EBV). Swamp’s service manager Matt Vozar and his staff had noticed signs of leaks in the exhaust plumbing, so they decided it would be best to replace them with bellowed up-pipes and new gaskets. The complete upgrade took about seven and a half hours, including slow-downs for our photography and lunch.
Vozar started by removing the air filter, turbo inlet tubing, intercooler boost tubes and intake manifold to access the turbo and pedestal. With the exhaust inlet and outlet disconnected, Vozar removed the turbocharger and its pedestal, since a pedestal designed to work without the EPV would replace the latter.
With the turbo on the workbench, Vozar removed the compressor housing and replaced the factory cast wheel with a machined billet Wicked Wheel2 from Dieselsite, which forms the heart of this upgrade. The fully balanced Wicked Wheel2 is lighter than the factory cast wheel, which allows for faster spooling. It’s also more aggressive than the factory part, using 10 blades in two different lengths in place of the factory’s nine equally sized blades. This design allows it to grab and compress more air on each revolution.
REMOVING THE EBV
With the compressor side of the turbo buttoned up, Vozar flipped it over to remove the outlet flange and delete the EBV flapper. Because the shaft and flapper are positioned in the middle of the exhaust flow, they impede that flow slightly even when open. In a worst-case scenario, the valve can stick in a partially or fully closed position, resulting in excess backpressure and poor engine performance.
To remove the assembly, Vozar ground away the rivets holding the flapper and then slid the shaft out of the outlet flange. He then used a welder to seal the hole from the shaft before cleaning the mounting surfaces and reinstalling the outlet on the turbo. For owners who don’t have access to a welder, Dieselsite offers a complete non-EBV outlet flange.
STOPPING THE LEAKS
Before the upgraded turbo could be reinstalled, Vozar had to address the leaking up-pipes and collector. The up-pipe kit from Swamp’s includes new installation hardware, and that turned out to be a good thing as all four of the rusty bolts securing the pipes to the manifolds broke when Vozar attempted to remove them.
With the bolts gone, the up-pipes came out of the truck with almost no effort, even though both were still bolted to their respective collectors. Inspection showed that the donut gaskets had completely failed, allowing serious exhaust leaks. The new up-pipe kit uses bellows to allow for expansion and contraction without stressing the gaskets, as occurs with the factory design. This is one of many examples of aftermarket parts having a superior design compared to what came from the factory, and the new setup should last Uriah much longer than the original did.
PUTTING IT ALL BACK TOGETHER
In order to ease installation, Vozar mounted the passenger side up-pipe to the collector on the workbench, and then lowered it into position from the top side of the engine. He then installed the driver’s side up-pipe and finger-tightened the exhaust manifold bolts from below the truck before tightening the collector hardware. He left the manifold hardware finger-tight until the turbo could be installed and the exhaust inlet and outlet attached in order to allow for any necessary movement.
Before reinstalling the turbo, Vozar bolted in a replacement turbo pedestal without an EBV actuator. The new pedestal from Swamp’s includes four new O-rings to seal the pedestal to the engine and the turbocharger to the pedestal. New O-rings are important, as re-using the old ones could result in oil leaks.
The original intake manifold boots showed signs of leakage, so Vozar cut and installed new silicon tubing to replace them before reinstalling the intake manifold, intercooler boost tubes, and air cleaner. One last trip under the truck to tighten the up-pipe-to-manifold mounting bolts, and the upgrade was complete.
ON THE DYNO: MISSION ACCOMPLISHED
We wanted to see what kind of numbers our improvements gave us, so we took the truck to Bean’s Diesel Performance for a few runs on their new Dynocom chassis dyno. Ryan Bean strapped down Uriah’s F-350 and made three successive dyno pulls. The truck put an average of just over 370 horsepower and almost 800 lb-ft of torque to the rollers, with peaks of 372.4 horsepower and 795.4 lb-ft of torque measured on one run. When Bean switched to a lower tune, the torque dropped slightly but peak horsepower actually rose.
Uriah’s 7.3L Power Stroke was rated at 250 horsepower and 505 lb-ft of torque at the flywheel when it left the factory, which meant that somewhere between 200 and 225 horsepower was actually being put to the ground.
The truck is now making nearly double the power with improved drivability, better towing capability, and increased fuel economy—and this with nearly 150,000 miles on the odometer. We’ve seen 6.7L Power Stroke trucks show 340 horsepower and 650 lb-ft on the dyno, which means that Uriah now has a truck that makes more power than a brand-new Ford, and he hasn’t spent anywhere near the new truck’s $50,000 price tag. Our mission for this project has most definitely been
Competent DIYers can handle a job like this, but it’s important to exercise caution when working in and around the engine of your truck, especially when dealing with hot components like the turbo and exhaust system. If you plan to tackle this upgrade yourself, be sure to practice safe shop techniques to prevent damage to the truck and injury to yourself. And be sure to give yourself plenty of time to complete the job—you don’t want to be rushed into making a mistake that could potentially hurt you or harm the truck.
Swamp’s Diesel Performance