Project 7.3L Powerstroke My2K: Part 9

Buying Used and Getting Back to Basics

It’s been a year since this truck was purchased to help generate, what we hope, is good technical content around the 7.3L Power Stroke. We’d hoped to be able to share more in-depth information on the strengths and weaknesses of this platform, and what can be upgraded for better reliability. What parts are worth upgrading and why? Mostly, we just wanted to show the guys out there still driving a twenty-year-old truck, that while it’s old and outdated compared to the new trucks, they can still be plenty capable when it comes time to work.

KC Turbos Stage One

With the most basic upgrades already taken care of, and a lot of the common failure points resolved, it’s time to jump into some of the more in-depth installs, like replacing the worn out and undersized stock turbo and replacing the leaking exhaust up-pipes. We’ve done articles on 7.3L turbo upgrades before, and one of our favorites to date was a KC300X that was installed on a 1996 Power Stroke project a few years back. Leaning on that knowledge, we reached out to KC Turbos for their opinion on the best option for our mild daily driver/tow rig build. With plans of Stage 1 or 1.5 injector down the road, we needed the air to support 400hp but didn’t want to give up low-end spooling, so we ordered the Stage One drop-in turbocharger from them, along with their high flow outlet and non-EBPV turbo pedestal kit.

In factory form, the stock turbocharger on the 1999.5-2003 7.3L trucks, wasn’t a bad little setup. But with added fuel from tuning or larger injectors could quickly show its pitfalls. With more than factory power levels, the stock turbo is prone to compressor surge while towing and can run out of air quickly, leading to hot EGTs, and smoky driving conditions under load.

In speaking with KC Turbos owner, Charlie Fish, he suggested their latest rendition Stage One stock replacement KC300x turbocharger because of its use of their Gen 2 63m compressor wheel, and Borg Warner SX-E based 68mm turbine wheel, they had specifically designed and produced for the 7.3L applications. Since the Super Duty trucks came factory equipped with a wastegate exhaust housing, the tighter .84 housing offers the best of both worlds for both drivability and high RPM EGT/boost control. For our build, their 63mm compressor wheel would move enough air to support a Stage One injector while running great on stockers, should we never get around to upgrading them. The Gen 2 63mm wheel offers great spool-up and a broad power curve thanks to its seven-by-seven extended tip blade design and profile. Paired with their uniquely styled compressor cover, the larger map groove offers excellent surge control while towing.

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The original 7.3L Ford Powerstroke Turbo Charger — This appears to be the original turbocharger on the truck and at 170,000 miles, we think it’s paid its dues. While there are some less expensive options on the market to upgrade the factory unit to eliminate surges and improve airflow, a complete replacement unit seemed to make the most sense for this truck.

Since our factory pedestal has been leaking oil from the warmup valve rod, this was the perfect time to

eliminate that problematic system from the truck together. This offers two benefits. First, we’ll

eliminate that pesky oil leak. Second, we can remove the restrictive warm-up butterfly valve from the

exhaust outlet and free up the exhaust to help bring exhaust temperatures down some more. The high-flow outlet removes any restrictions on the exhaust side of things, offering the absolute best in EGT control.

Riff Raff Up-Pipes

While speaking of exhaust, the factory Ford exhaust up-pipe design leaves a lot to be desired. Our factory up-pipes have been leaking for some time, and now is the perfect time to replace them. The stock units use a simple crush donut to seal the pipes to the turbine collector, but after thousands of heat cycles, these crush donuts just simply don’t hold up. Riff Raff Diesel is another great shop that focuses primarily on the Power Stroke platforms and has really put a lot of effort into making products that not just resolve factory issues but improve performance or efficiency while they’re at it. Their bellowed up-pipe kits for the 7.3L were designed to replace the donut gasket with a better-performing design that fits as OEM pieces would. They are built right here in the USA using aircraft grade 321 Stainless Steel, ensuring they’ll never rust or crack. By incorporating a bellow into the pipe, you’ll still get the flex and expansion needed in the up-pipe with continuous heat cycles, while keeping a leak-free seal.

Stock 7.3L Ford Powerstroke Turbo — The 1999+ trucks made it much easier to swap turbochargers than the previous 1994-1997 trucks, as Ford moved over to v-band style exhaust inlet and outlet. The change in firewall and cowl design also makes it much easier to access everything with your hand tools, including the pedestal bolts.

Intake Y-Bridge intercooler pipes — With the intercooler pipes removed, we needed to remove the ‘spider’, which is the x-shaped unit sitting in the valley of the engine. With the spider out of the way, you have easy access to removing the turbocharger and up-pipes.

With the v-band clamps all removed and the joints broken loose, the last step to removing the turbo is removing the two pedestal bolts. The turbo can then be lifted off its perch and finagled up and out of the engine bay exposing the exhaust up-pipes back against the firewall and the factory leaking pedestal.

Results

After the installation was complete and we were able to use KC Turbos’ nifty boost leak detector to ensure the system was sealed up tight we made our first drive around town and were blown away at the responsiveness of this 63/68 turbocharger. You’d never know this turbo was larger than stock, aside from the slightly different tone it produces. While it’s quite a bit larger than the stock turbo, with the exhaust leaks sealed up and the .84 a/r exhaust housing, the turbo makes boost effortlessly. Whether we’re leaving a stop light or rolling into the throttle when cruising, boost comes up easily and really limits the smoke output of the exhaust. The power band feels wider, and our boost pressures have come up to the peak in the 24-25psi range. We’ve seen over a 200-degree drop in our EGTs at the wide-open throttle and towing trailers have become effortless.

7.3L Ford Powerstroke Turbo Exhaust Y-Bridge — With the turbocharger out, it was also the perfect time to address the failure-prone exhaust up-pipes. These pipes direct exhaust from the exhaust manifolds to the turbine inlet of the turbocharger. The factory design uses a crush-style donut, that after time, thousands of heat cycles will lose their ability to seal. This leads to poor turbocharger performance, excessive EGTs, and a sooty mess under the hood.

The factory turbocharger is equipped with a warm-up valve on the exhaust side, which will close on cold start-ups to allow the engine to reach operating temperatures sooner. The downside here is the actuator used to open/close that butterfly often deteriorates in the pedestal and will create a substantial oil leak. Which you can obviously see is the case here.

Factory EBPV Turbo Pedestal — To eliminate the chances of this happening in the future, we’ve opted to remove the warm-up valve altogether. For this change, the turbo must be equipped with the higher flower non-EBPV outlet and you’ll need a non-ebpv pedestal, which we sourced from KC Turbos when we ordered our new 63mm unit.

When the pipe will come out of the upper collector without removing the bolts and breaking the seal on the crush donut, you know it’s time to replace the up-pipes.

In upcoming issues, we are going to address a few more things on the charge air system, like an intercooler upgrade, intake plenum repair, and diving into a couple of other exhaust-related repairs. We also need to spend some time on the interior with some replacement leather seat covers and address a mild coolant leak we’ve developed recently.