Police Interceptor

Published in the August 2008 Issue August 2008 Feature, Spotlight, PowerStroke

Police InterceptorNo, the owner of this truck isn't Joe Friday, but he is an armed officer of the law. Abiding by the laws which he helps to uphold in the great state of Colorado, Tom Steen spends his nights patrolling the toughest streets of Denver on the lookout for drug dealers, gang members and stone cold thugs. He may patrol the streets in your typical everyday police issue Crown Vic, but this is his preferred vehicle, a 1996 F250 7.3L Power Stroke.

When Steen first bought the truck in July, 1998, it was his perfect truck, everything he ever wanted and needed in a pickup. But just like every guy out there, the way things are began to not be enough and the craving for more latched on. First off, he added a Mito Corporation auto-dimming mirror with a built-in compass, a drop-in bed liner, some mud flaps and a complete alarm system.

Working the beat of downtown Denver day in and day out, Steen is proud to be an officer of the law. So it was just natural to wire a set of Wheelen strobes into the back-up lights and turn signals. Next was making that old diesel burner a little quieter in the cab. Second Skin sound deadener was applied to the doors, floor, firewall and rear cab wall.

This turned out to be a very time-consuming project that resulted in a lot quieter road manners while traveling the streets of Colorado.

Breath of Fresh Air

The first performance modifications to the 7.3L powered Ford started in 2003 with upgrades to the intake and exhaust systems. Steen first purchased a Tymar style intake, which has since been upgraded to a new custom AFE element from Airflow Systems.

On the exhaust side, a Banks 3-inch down pipe and a Banks tail pipe section were installed. That system has also since been changed out to a Magnaflow 4-inch kit. Steen says he didn't notice much difference from a performance standpoint, but the addition of an Aeroturbine muffler pretty much eliminated the drone from the pieced together Banks kit. With just the intake and exhaust upgrades the truck dynoed 218 rwhp-a little better than stock but still far from where he wanted it to be.

Making Cool Power

In the search for more power he purchased a Diesel Power chip for the truck and improved the power output another 36 hp. With just over 250 hp getting to the ground, the stock non-intercooled motor was starting to see its limits, temperature wise.

So Steen bought and installed a complete Banks Intercooler system. Installation took some effort with some cutting to the core support for clearance of the new intercooler pipes, but the fit and finish of the kit was excellent and looked almost factory. Hoping to improve turbo response, a smaller 1.0 exhaust housing was also bolted onto the stock turbo charger. These two modifications worked very well together, especially at the higher altitudes (6,800 feet) in Colorado. Spool-up was excellent and the new intercooler allowed him to use every ounce of the power the chip provided while towing without having to back out due to high egts.

Knowing the strain the power and heavy load would put on the differentials and transmission, some PML transmission and differential covers were swapped onto the truck for a little added fluid capacity.

Injector Swap

In 2005 Steen finally gave in and decided it was time to have the injectors re-worked; the tiny 98cc injectors needed some improvements. Swamps Diesel was called and stepped up to the plate with some of its 150cc Stage One injectors.

The new injectors really woke the truck up and made a huge difference in the power department. On the next trip to the dyno, power was up to 368 hp with 650 ft lbs of torque. The truck was much better to drive and even with the camper on the truck, he could go just about as fast as he wanted, no matter what the grade. However, it didn't take long for downsides to the big power to show up.

Transmission Upgrades

The first downside was that just a few months after the injectors were swapped out the stock E4OD tranny started to slip, especially if he had to work the truck real hard-like pulling a grade with the camper on.

When the time came to replace the transmission there was only one option in Steen's mind, a BTS Transmission. Since the stocker was still holding up he made the drive back east to Brian's Truck Shop in Lead Hill, AR, for a complete rebuild. BTS is regarded as one of the best E4OD builders in the country and he only wanted to do this one time.

The newly rebuilt transmission works a lot better than the old stock unit ever dreamed of. The tranny is still holding strong and has stood up to everything Steen has thrown at it, including a few sled-pulls and trips down the drag strip. To improve cooling, a transmission cooler from a Ford V-10 was mounted right behind the front bumper.

Low High Pressure

The second downside was throwing a check engine light every time he needed to use the throttle. The stock 15-degree high-pressure oil pump just couldn't keep up with the new oil requirements of the modified injectors. After doing some research, it was decided that a factory Ford Super Duty 17-degree pump would probably be enough to solve this issue. With the higher flowing 17-degree pump Steen noticed a little better throttle response and much better top-end power. In addition, the truck wasn't throwing that annoying check engine light under load anymore.

It's Electric

Next up on the mod list was converting that mechanical fuel system over to an electric setup. The stock mechanical fuel pump was letting the pressure drop clear down to 30 psi at wide-open throttle, far from acceptable.

No one really offered a complete system for the older Power Strokes so Steen built his own. Based off the Ford Super Duty electric pump style system, he used a stock Super Duty pump and added pre- and post-Caterpillar fuel filters.

He fabricated his own mounting brackets and stainless tubing to run to the motor. The filters and pump were mounted down on the inside of the driver's frame rail, allowing easy access for filter changes. One of the side benefits to this new system was a much cleaner engine valley by eliminating the factory pump and filter bowl. With the Stage One injectors the single Super Duty pump has had no problems maintaining the requested fuel pressure.

Breath of Fresh Air (Part Two)

Looking for the next step in performance, Steen knew that the somewhat smallish stock turbo was restricting his airflow. Stepping up to a larger framed turbo, like those for a Super Duty 7.3L, should offer some great improvements, in both power and egts. So he purchased one of the new Turbonetics ball-bearing drop-in units.

Unfortunately, this truck is not a Super Duty, so it wasn't quite a drop-in project. To make the new turbo work on the older body styled 7.3L, a lot of the factory Super Duty parts can be used. The parts were acquired to make the transition, which included a bellowed up pipe kit (eliminates the troublesome donuts at the juncture of the collector and up pipes), a turbo pedestal without the exhaust backpressure actuator from Truck Source Diesel and new exhaust manifolds and hardware from International. Steen also had all the new parts ceramic coated, to improve heat retention and exhaust velocity.

For the most part, everything was pretty much bolt-on. New ends needed to be fabricated on the down pipe and the compressor outlet adapter needed some attention. But Steen says the new turbo has worked great, with quick spool-up and great road manners as well as no surge or barking during shifts.

Computer Tweaks

The most recent performance improvements came in the form of computer programming. With the help of Jody Tipton of DP Tuner, Steen was able to have the truck live tuned right there in Colorado. It's not often you get the opportunity for one of the best tuners in the country to tinker on your truck right on the streets of your hometown. He says being able to have the truck tuned to act the way he wanted it to was invaluable. Just the transmission shifting improvements alone made the live tuning session well worth it.

The new tuning also improved quarter-mile times some, with an all-time best of 14.9 at 89 mph. Not bad for a 12-year-old truck at track over a mile high-Bandimere Speedway (5,900 feet).

What's Next

At this point, Steen is pretty happy with where the truck is power-wise. But just like any other diesel guy, he knows there's always room for more. He has updated his gauges to the new Performax line from Isspro and also added an OBD II Aeroforce scan gauge.

Next on his mod list is possibly upgrading the braking system with some frozen and slotted rotors with performance friction pads up front.

Steen attributes his addiction for Power Stroke performance to his friends at the Colorado Power Stroke Club and the members of the PowerStrokeNation.com forums. If you're into the tuner and ricer market, this is one police officer you won't want to mess with. Not because he'll arrest you for street racing-but because he's got a hopped up diesel that'll show you how it's really done.

  • Like what you read?

    Want to know when we have important news, updates or interviews?

  • Join our newsletter today!

    Sign Up
You Might Also Be Interested In...

Send to your friends!



Recapping the Vegas Show

Sneak Peek

Already a subscriber? Please check your email for the latest full issue link.