How to Make My Freightliner Go Faster

by Richard Rowe
Thomas Northcut/Photodisc/Getty Images

Named for a class of transoceanic cargo vessels, Freightliner went into business in 1942 with the express purpose of creating a go-anywhere, land-driven equivalent. Now owned by Daimler, Freightliner trucks remain just as versatile as ever but rely on a variety of different engines. Following Daimler's acquisition of Detroit Diesel in 2006, Freightliner switched almost exclusively to engines from that manufacturer. Increasing the top speed of a Freightliner is fairly simple since the powerful Detroit is more than capable of propelling the truck far past its computer-governed speed.

Step 1

Acquire a power-tuner or take your truck to a dealership with the equipment necessary to re-tune the engine. Introduced in 1987, the 12.7-liter Detroit Series 60 and its 14-liter replacement remain a standard to this day. In stock form, these engines produce between 250 and 575 horsepower but can produce as much as 850 with a few minor computer tweaks.

Step 2

Re-tune the computer to increase turbocharger boost and increase fuel injection timing. This is fairly simple on Series 60 engines that use computer-controlled common rail injection or Amplified Common Rail Injection but may require physically altering the injector pump or injector sizes on mechanically-controlled engines. However, all modern Detroits use computer controls, so re-tuning up to 800 horsepower is generally only a matter of selecting a power setting using the computer tuner.

Step 3

Disable the electronic governor. Increasing engine power will only increase your pulling power; without removing the speed governor, you're not going top see any increase in speed. Trucks are drag-limited, meaning that aerodynamics play the largest role in top speed. The average truck only needs about 350 horsepower to go 90 mph. After removing the governor, a 500 horsepower truck will do about 100 mph; 650 hp gets you about 110 mph and 850 hp gives you around 120. Hypothetically, you'd need around 4,000 horsepower to hit 200 mph.

Install a massive nitrous fogger system. Installing a nitrous system on a Series 60 is just like doing it on any other engine. You'll need to drill and tap the intake runners to accept the spray nozzles, and then connect them to a nitrous bottle and a fuel source. For the diesel engine, you might consider using propane injection to supplement the nitrous instead of diesel since it will help control combustion chamber temperatures. A stock Series 60 block is capable of withstanding over 3,000 horsepower's worth of boost or nitrous, so inject as much as you need to meet your speed requirements.

More Articles