Matt Maier’s 11-second, Daily-Driven OBS Ford

While today, folks buy diesel trucks for a whole host of reasons, the diesels of old were often purchased for one purpose: to tow. Figuring out how well they responded to power-adders would come with time. That scenario couldn’t have been more true for Matt Maier and his ’97 F-250. Twelve years ago, when factory oil burners weren’t near the behemoths of today, he was so impressed with the way his friend’s bone-stock, 125,000-mile 7.3L pulled a trailer that he leapt at the chance to buy it. At the time, he couldn’t have imagined—even in his wildest dreams—that it would one day run low 11s and still be capable of towing anything he needed it to.

Even though Maier’s OBS Ford was originally intended to tote his toys to the mudhole or the trailhead, in time the truck would change his entire world. Over the course of the last decade, and after having worked for the likes of Beans Diesel Performance, Full Force Diesel, and now Irate Diesel Performance, his daily-driven tow rig gradually morphed into one of the most consistent trucks in diesel drag racing. Along the way, he’s blown head gaskets, he’s toasted transmissions, and he’s even bent connecting rods—all in an effort to test the limits of the 7.3L platform and prove that the HEUI-fired V8 can be competitive in the modern common-rail era.

Race-Prepped 7.3L

With round after round of Index racing at 650 hp, the occasional attempt to break into the 10s at 900 hp, and spraying the truck to more than 1,200 hp on the chassis dyno all under his belt, Maier certainly did his part in proving what the 7.3L’s factory forged connecting rods could handle. But to bring more peace of mind into the equation, he decided to piece together a built engine in 2016. A balanced rotating assembly consists of the OEM crank (reinforced via a main bearing girdle), Carrillo rods, de-lipped and coated factory-based Mahle pistons, and a billet flex plate from Precision Industries. The stock cylinder heads feature Irate Diesel Performance beehive valve springs, while ARP studs fasten them to the block.

After years of making big power on factory forged-rod bottom end 7.3Ls, Matt Maier finally bit the bullet and put together a built engine back in 2016. His reinforced 7.3L sports an Irate Diesel Performance girdle, ARP main studs, Carrillo forged rods and de-lipped cast-aluminum Mahle pistons. The pistons were ceramic coated up top, their skirts treated with dry film lubricant, and an oil shed coating was also applied to the bottoms, all at High Rev Technology. The factory-based cast-iron heads received a six-angle valve job, Irate Diesel Performance beehive competition valve springs and ARP head studs.
Even though Maier has tried various S400 turbochargers in the past (including an S472 SX-E and an S476), he has always come back to the tried-and-true BorgWarner S467.7. The forged milled wheel (FMW) charger spools quick despite being equipped with a 1.10 A/R turbine housing (for optimum flow up top), and it’s also been equipped with a 360-degree thrust bearing. A turbo mounting system from Irate Diesel Performance—complete with a pedestal, T4 collector and 304 stainless steel up-pipes, intercooler piping, intake Y, and cold-air intake—integrates the S467.7 into the lifter valley.

Proven Combination

Aside from the internal engine upgrades, the rest of Maier’s parts combination is essentially a carbon copy of what he’s been running for the last six years. The same BorgWarner S467.7 turbo and Irate Diesel Performance T4 mount assembly produces and routes 60 psi or more of boost into the engine. The same Full Force Diesel 350/200 hybrid injectors sit under the valve covers, fed consistent fuel supply courtesy of an Irate competition system. And the same dual high-pressure oil pump system allows the injectors to perform at their full potential. Last but not least, Maier still depends on proven tuning from Gearhead Automotive Performance to get him down the track consistently, cleanly, and reliably.

If you’re gonna send 75 psi of boost through your intercooler piping like Maier does, you better have some boots than can handle the pressure. Thanks to a set of Irate Diesel Performance multi-ply silicone boots and high-strength T-bolt clamps, elevated boost levels are never a problem.
At the front of the lifter valley you’ll find two high-pressure oil pumps courtesy of the time-tested BTS dual HPOP system (now owned and offered by Full Force Diesel). The purpose of the dual pumps is to feed as much oil volume as possible to a set of Full Force Diesel 350/200 hybrid injectors. With enough high-pressure oil in the mix to allow the 350cc, 200%, nozzle-equipped injectors to run at their maximum potential, Maier’s truck clears more than 650 rwhp on fuel alone.
An Irate Diesel Performance competition fuel system keeps the 350/200 injectors supplied with a steady flow of diesel thanks to a Fuelab Prodigy pump, -8 AN line to -6 AN lines feeding each cylinder head, and a regulated return with an adjustable regulator. Fuel begins its route to the Irate system via a billet-aluminum sump from Beans Diesel Performance.
To hold up to 900-rwhp passes at the track, 550 rwhp while towing and streetable daily driving tunes, Maier runs a Dorsey Diesel Stage 4 E4OD. The top-shelf transmission makes use of Raybestos GPZ clutches, all billet shafts, a billet overdrive planetary and forward drum, a hardened sun shell, modified pump, custom-built valve body, and it’s topped off with a triple-disc DPC converter with a stock stall speed. The built automatic keeps its cool courtesy of a 40-row Derale Performance remote-mount transmission cooler in the bed.

Manually Shifted, Billet E4OD

After delayed or flared shifts cost him precious time and gear change inconsistencies cost him races, Maier devised a homemade shift box that let him take matters into his own hands. Now he can lock the converter whenever he wants and command each upshift at the precise interval he needs it. The shifts themselves are kept firm and crisp thanks to a Stage 4 transmission from Dorsey Diesel, which features a valve body that’s been custom-tailored to Maier’s needs. The four-speed automatic is also furnished with billet input, intermediate and output shafts, a billet overdrive planetary and forward drum, and a billet triple-disc converter from Diesel Performance Converters.

After the stresses of utilizing big horsepower in four-wheel drive left the factory TTB Dana 50 in ruins, Maier swapped to a solid axle in its stead. The King Pin Dana 60 was sourced from a ’79 F-350 while the leaf springs were pulled off a ’95 1-ton. Other than adding a set of premium Warn locking hubs, the Dana 60 is completely untouched.
With the help of friend and longtime 7.3L guru, Steve Constable, Maier built a stout set of traction bars for his OBS. Constructed from 2×2-inch, 0.25-inch-wall square steel tube, the bars incorporate heim joints from RuffStuff Specialties and bolt-on axle mounts sourced from a set of CalTracs.
Once you notice the gooseneck ball in the bed and the Firestone air springs sitting atop each rear leaf pack, it’s apparent that Maier still uses his 7.3L to tow. In fact, it’s often hooked to his 40-foot trailer, which tips the scales at 15,000 pounds when fully loaded. At the dragstrip the air springs are used to keep the front end from unloading during boosted four-wheel-drive launches.

Fully Vetted, Old School Sleeper

Having conducted nearly a decade’s worth of his own personal R&D, Maier knows which parts allow you to get the absolute most out of a 7.3L Power Stroke—and his truck reflects that in every way. By keeping things simple and sticking to a proven parts combination, Maier’s OBS has inspired countless other 7.3L builds over the years. And who could overlook the fact that the truck’s factory Alcoas, stock-like ride height, and conventional-exit exhaust make it the ultimate sleeper?

Using the Hydra chip platform from Power Hungry Performance, Maier navigates a host of daily, tow and race-ready tuning files from Gearhead Automotive Performance. An all-out tune that calls for 3.2 milliseconds of pulse width makes for consistent 7.70- to 7.75-second eighth-mile ETs on fuel, while a nitrous file has yielded bottom 7s in the eighth and low-11-second quarter-miles in the past.
Even with great custom tuning, the factory electronics aboard the OBS Fords can cause various intermittent shifting issues, which translate into inconsistencies at the track. For full control over the shift points of the transmission, Maier uses a shift box he built himself. A typical pass entails a boosted launch, followed by the 1-2 shift and converter lock-up taking place approximately one second later. From there it’s a matter of commanding upshifts at the appropriate rpm.
In the cab, and amid a well-preserved factory interior, you’ll find a set of Isspro Performax gauges along the A-pillar. The analog units, which incorporate an electronic signal processor that allows them to be daisy-chained together and swapped out in seconds, include a 2,000-degree pyrometer, 100-psi boost gauge, and 100- to 280-degree trans temp gauge. A fourth gauge, used to read fuel pressure from 0 to 100 psi, is located on the lower dash. The Edge CS monitor is primarily used to display the 10 to 12 psi of boost Maier likes to see before launching the truck.
Just in case the two .125 Nitrous Express solenoids mounted behind it aren’t enough, a Super Shark solenoid with a .157 orifice can be brought into the equation—although Maier typically reserves it solely for “playing around on the dyno.” The two-track stages take the truck from 655 rwhp on fuel to just under 900 rwhp. With the third solenoid in the mix, Maier has cleared more than 1,000 rwhp on the dyno. No stranger to ghetto fogging, the truck has even made 1,226 rwhp on the rollers by spraying nitrous straight into the intake, which was a 7.3L horsepower record for a period of time.
Even in the modern, 20-plus-inch wheel craze, Maier has retained the old school look of his OBS Ford in the form of the 16×7-inch factory Alcoas. Believe it or not, the same BFGoodrich All Terrains that are used to run errands and tow his toys to the trailhead are also on the truck when he races Index classes. It’s when the 30-inch slicks get bolted on that you know Maier plans to activate the nitrous.
Although Maier has been drag racing competitively for the better part of a decade, his crowning achievements came with his back-to-back 11.90 Index class wins at the Diesel Thunder Mississippi events in 2015 and 2016. Aside from beating out a stellar field of trucks on both occasions, the second victory sticks out in his mind the most due to the fact that—in order to break in the built 7.3L he’s currently running—his OBS was used to haul his Super Duty tow rig 500 miles to the event.
[divider] Specifications [/divider]

1997 Ford F-250

Owner: Matt Maier
Hometown: Readyville, Tennessee
Odometer: 252,000 miles
Engine: 7.3L Power Stroke
Short Block: Irate Diesel Performance girdle, ARP main studs, Carrillo rods, de-lipped Mahle pistons coated by High Rev Technology, Precision Industries billet flex plate, Fluidampr harmonic balancer
Heads: Irate Diesel Performance competition valve spring kit, Smith Brothers chromoly pushrods, 6-angle valve job, ARP head studs
Fuel: Full Force Diesel 350/200 hybrid injectors, Irate Diesel Performance competition fuel supply system with Fuelab Prodigy pump and regulated return, Beans Diesel Performance fuel tank sump
Oil: Full Force Diesel dual HPOP system, Melling low-pressure oil pump
Air: Irate Diesel Performance T4 turbo mounting system, BorgWarner S467.7 with 1.10 A/R turbine housing and 360-degree thrust bearing upgrade, early ’99 aluminum Super Duty intercooler, Irate Diesel Performance 3-inch aluminum intake plenums
Exhaust: 3-inch Irate Diesel Performance downpipe, 4-inch MBRP system
Injectables: Nitrous Express-based nitrous system with two .125 solenoids for the track and additional .157 solenoid for the dyno, water injection (towing only)
Electronics: Power Hungry Performance Hydra Chip with custom tunes from Gearhead Automotive Performance, Isspro pyrometer, fuel pressure, boost, transmission temp gauges, Edge CS monitor
Transmission: Dorsey Diesel Stage 4 E4OD with DPC triple-disc stock stall converter, billet input, intermediate and output shafts, billet overdrive planet set and forward drum, hardened sun shell, Raybestos GPZ clutches, Derale Performance remote-mount 40-row transmission cooler, homemade shift box
Horsepower: 655 hp (fuel, track and dyno); 900 hp (nitrous, track); 1,226 hp (ghetto fog, dyno)
Torque: 1,280 lb-ft (fuel, dyno); 2,107 lb-ft (ghetto fog, dyno)
Tires: 305/70R16 BFGoodrich All Terrain
Wheels: 16×7-inch factory Alcoa
Axles/Suspension/Steering: Solid axle conversion with ’79 F-350 King Pin Dana 60 (front), ’95 F-350 front leaf springs, Warn premium hubs, 3.55 gears (front and rear), homemade 2×2-inch 0.25-inch wall traction bars with RuffStuff Specialties heim joints, Firestone air springs, Bilstein 4600 shocks (front and rear)

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