Since 1985 the High Mobility Multipurpose Wheeled Vehicle (HMMWV or Humvee) has been the mainstay workhorse for our nation’s military. Originally powered by a General Motors 6.2L naturally aspirated diesel, subsequently upgraded to 6.5L and ultimately to a turbocharged 6.5L, the Humvee has never been considered a particularly high-performance machine.
One turbo 6.5L equipped unit that was tested on the Banks chassis dyno produced only 113 horsepower at 3200 RPM and 219 lb-ft of torque at 2600 RPM. Measured at the wheels, these are certainly not stellar numbers, but sufficient to move an average military vehicle down the road. The problem is that modern Humvees have evolved beyond their average predecessors.
While the Humvee was originally designed as a basic troop carrier and general utility vehicle, field use has uncovered the need for additional armor, gunnery and communications equipment. Today a fully equipped Humvee can easily tip the scales at double its original design weight. Suddenly 113 horsepower doesn’t go as far and as fast as one might like, especially when someone is shooting at you.
The answer to the “weighty” problem starts with the Banks Sidewinder Turbo System. This is a complete update to the induction system of the 6.5L engine, replacing the factory turbo with an internally wastegated Banks Sidewinder turbo for improved boost control, adding a Banks intercooler and ducting to reduce charge air temperature and improve intake manifold density, and a replacement intake manifold for improved air distribution and reduced restriction.
The fuel system is amped up to match the new airflow capabilities with a new 4-piston injection pump and high flow injectors. Completing the system is a free-flowing Monster Exhaust system allowing the engine to exhale as well as it inhales.
The Banks Sidewinder system proved its mettle during a test session with an up-armored Humvee that weighed in at 14,400 lbs. showing a 58% increase in horsepower (from a meager 113 at the wheels to 178). Acceleration was 46% faster in a 0-60 mph standing start sprint, slashing the ET from 43.0 to 23.1 seconds. While the cumbersome beast would only attain 75 MPH in stock form, it flew to 87 MPH with the Banks kit installed, limited by the speed rating of the tires (speeds well over 95 mph are possible, though not condoned).
Added braking power is achieved with an integrated turbine-mount exhaust brake which increases stopping distance of the Humvee from 307.6 to 243.3 feet in 60-0 mph braking tests, a reduction of over 64 feet. Perhaps most impressive is the ability of the brake to slow the Humvee to 10 MPH on a 6% grade without the assistance of any wheel braking. In stock form, without the exhaust brake, the HMMWV accelerates to over 60 MPH on the same downhill course.
While the sea level improvement is substantial, the high altitude performance gain is even more pronounced. By testing at Pikes Peak through such racing endeavors as the super-turbo Freightliner and a twin turbo opened wheeled race car at its 14,100’, Banks have developed outstanding altitude compensation into the Sidewinder package. As for fuel economy: under all operating and altitude conditions, economy was improved as well.
Sadly, this kit was not offered to the general public and remains so to this day.