Classic Lines, Modern Appeal: A 350-HP OBS Ford

As proof that Blue Oval loyalists are still willing to spend money on first-generation Power Strokes, look no further than Blake Younce’s immaculate ’97 F-350. The Florida native has invested thousands in his old Ford over the past several years. Along the way, he’s improved the truck’s performance without sacrificing reliability, and added modern bling without abandoning the truck’s original, rugged look.

The forged-rod 7.3L Power Stroke in Blake Younce’s ’97 F-350 has accumulated 265,000 trouble-free miles in its 21-year tenure. To date, the only work performed under the valve covers has been to add a set of 150cc stock-nozzle Baby Swamp injectors from Swamp’s Diesel Performance. Beyond that, an Irate Diesel Performance T4 turbo mounting system, 6.0L intercooler installation, and Adrenaline high-pressure oil pump were added courtesy of White’s Diesel Performance in Nokomis, Florida.
At the heart of the Irate Diesel Performance T4 turbo system sits this S364.5 SX-E turbocharger from BorgWarner. Thanks to a forged-milled-wheel 64.47mm compressor wheel, 73mm turbine wheel in a 0.91 A/R housing, and a 360-degree thrust bearing available as standard equipment, this charger lights quick, flows nearly 400 cfm more than the stock turbo, and is considerably more reliable than the factory Garrett unit. Younce tells us the little S300 produces 35 psi of boost at full tilt.
To get the most out of his injector combination, Younce did away with the factory 15-degree high pressure oil pump in favor of an Adrenaline from DieselSite. While this high-volume pump is known to add 30 to 50 hp to 7.3Ls (depending on injector size), Younce says the biggest improvement he noticed came in the form of increased low-rpm drivability, particularly while towing.
An electric fuel system from Irate Diesel Performance—complete with a Walbro lift pump, readily available Baldwin spin-on filters, and regulated return—bolts to the frame rail and ensures 65 psi worth of diesel is always on tap for the injectors to use. The e-fuel system cleaned up the lifter valley by scrapping the factory fuel bowl assembly and also came with an adjustable fuel pressure regulator from Aeromotive.

But while Younce had owned the truck since 2002, it wasn’t until buying his son, Brock, a ’96 F-250 a few years ago that he began to take an interest in diesel performance. “He’s definitely the one to blame for me spending all this money,” Younce tells us. “He has gotten to know a lot of people who eat, breathe, and sleep diesel trucks, and it’s rubbed off on me.”


While the truck still makes use of the factory pickup in the rear fuel tank, a sump kit from Full Force Diesel was installed in the front unit. Both factory tanks combine with an in-bed auxiliary tank to offer 91 gallons of overall capacity.
Tying all modifications together in the form of custom PCM tuning was left in the highly-capable hands of Gearhead Automotive Performance. Younce navigates half a dozen custom-tailored tunes via a TS Performance six-position chip.
Once exhaust leaves an Irate 3-inch downpipe, it routes through a 5-inch diameter Diamond Eye turn down system with a 10-inch polished tip. Both the factory 10.25 Sterling and Dana 60 axles still house the original 4.10 gears, but each differential was treated to a little dress up thanks to an aluminum diff cover.
Settling down harsh upshifts and stopping rear axle wrap is a set of traction bars Younce pieced together himself. The frame brackets, axle brackets, and heim joints came from SoFlo Diesel, while Younce sourced the 2.5-inch-diameter DOM steel tubing locally. Both the frame brackets and tubes were paint matched to the rest of the truck.
While a Skyjacker leveling kit was bolted to the truck during our photo shoot (and for much of the truck’s life), Younce has since installed ’99 Super Duty leaf springs up front. In an effort to improve ride quality, a Precision Metal Fab reverse shackle kit went on at the same time.

After some research, Younce quickly learned the best way to add any substantial amount of horsepower to his 7.3L would be through the use of larger injectors. Acting on his findings, the factory 90cc injectors were ditched in favor of a set of Baby Swamp units from Swamp’s Diesel Performance. Installing the 150cc injectors marked the first (and only) time the valve covers have ever been off the heads. To retain stock-like reliability yet ensure plenty of high-pressure oil volume makes it to the injectors, an Adrenaline high-pressure oil pump from DieselSite sits in place of the factory 15-degree unit. Custom PCM tuning from Gearhead Automotive Performance—available via a six-position TS Performance chip— unlocks the full potential of the injectors and Adrenaline.



A set of chrome 20×12-inch Moto Metal MO962 wheels add some 21st century bling to the old Ford, while four 35×12.50×20 Toyo Open Country A/T Xtremes handle traction. To make the rear track width identical to the front, Younce runs a set of 2.5-inch spacers out back.
To keep EGT and intake temps down, an intercooler from a 6.0L Power Stroke lurks behind the front grille. The cutting and fabrication work required to make the intercooler fit was handled by White’s Diesel Performance. As we went to press—and because he had plans to up size injectors and run more boost—Younce had just ditched the 6.0L unit (equipped with plastic end tanks) in favor of an aluminum intercooler out of a 7.3L Super Duty application.

Supporting the Baby Swamp injectors is an OBS fuel system from Irate Diesel Performance. The electric fuel supply system scrapped the factory mechanical lift pump and fuel bowl assembly in the valley in favor of a proven Walbro unit (and its corresponding Baldwin filters), which is mounted along the frame rail. Irate’s system also provided for the retention of the factory selector valve (so both fuel tanks could still be utilized) and included a regulated return, complete with an adjustable Aeromotive regulator that keeps fuel supply set at a steady 65 psi.


Younce knew the factory turbocharger would be a weak link, so it too would go by the wayside. Opting to run a T4 turbo mounting system from Irate Diesel Performance made it possible to utilize one of the industry’s latest gems: the S364.5 SX-E from BorgWarner. Offering a substantial increase in airflow over stock, the 64.5mm unit spools quickly, builds 35 psi of boost, and features a 360-degree thrust bearing for maximum durability. The S300 routes air through a 6.0L intercooler and a set of Irate’s 3-inch diameter intake plenums before entering the engine.


While the E4OD found under Younce’s F-350 isn’t the factory version, it was rebuilt using a TransGo shift kit and select other internal upgrades a short time ago. To date, the refreshed automatic has yet to skip a beat behind the now-potent 7.3L Power Stroke, which sends more than 400 hp and 800 lb-ft of torque its way.


Ushering the OBS into the new age, Younce bolted a set of 20×12 Moto Metal wheels to the axles and cleared the headlights, tails, and cab lights—but he didn’t go overboard. After all, the truck still sports the factory bumpers, mirrors, interior, and a set of era-appropriate hoop steps. To make the truck pop again, Younce recently had it repainted the same Indigo Blue it left the assembly line with.

In his first-ever attempt at drag racing, Younce piloted his F-350 to a low-15-second quarter-mile—not bad for a truck that would’ve run 19s in stock trim. Thanks to everything he’s added to the old Ford, he can keep up with the newer trucks on the road, get from point A to B in ultra-reliable fashion, and turn a lot of heads while doing it.
Roughly three years ago, Younce addressed the truck’s fading factory paint. The job was undertaken by his neighbor, Jon Bibler, who restores cars for a living—and the results are second to none. Once the truck was painted, Younce put the leftover material to good use in the form of coating all intercooler pipes the same shade of Indigo Blue.


With one quick look at the truck, you can tell Younce plans to hold onto it for a while. Old body style Ford owners don’t invest in a completely different turbocharger system, an electric fuel system, or go through the trouble of adding an intercooler, and especially a fresh paint job unless they care deeply about the vehicle. “This will probably be the only diesel truck I’ll ever have,” Younce confirms. “I like old-school stuff and you just don’t see a lot of these trucks in good shape anymore.” With double the factory horsepower, a blend of square-body ruggedness coupled with modern curb appeal, and rock-solid reliability, it’s hard to argue with his decision to keep it for the long haul. DW

You May Also Like


From Work Truck to 942 Rear Wheel Horsepower Beast A lot of people buy diesel trucks knowing that they’re going to load them up with […]

The Purple People Eater

A ’95 F-250 Packing a Solid Axle,  Built 7.3L, and 600-Plus HP It was a truck Steven Giordano had seen listed on his local Craigslist […]

KEG’S HAULER: A Truck Concept Takes Shape

Robbie Bryant is the owner of Keg Media, a group that specializes in assisting clients that do business in the automotive aftermarket. They do this […]

Randall’s Performance: Modified 2015 Silverado

Brian Randall — owner of Randall’s Performance in Gladstone, Illinois — wanted to put together a demo truck for his shop to show off the […]