The current-day BOSS 302 Mustang is one of the hottest Mustangs Ford Motor Company has ever produced – it performs outstandingly on the street and at the track. Recently the engineers at Ford Racing Parts thought they could improve on the mousetrap, so they set out to do exactly that in a number of steps that are easily achievable and provide a substantial power improvement.

The BOSS relies on a tunnel-ram style composite intake manifold; sourcing the Cobra Jet intake manifold [PN M-9424-M50CJ] from the company’s limited-edition race cars provides one heck of an improvement. The CJ design actually began from the roots of the BOSS manifold, then the Ford Racing Parts engineers increased the cross-section of the runners and increased the plenum volume to permit even more airflow into the 5.0L Coyote engine’s four-valve cylinder heads.

In a nod to the increased airflow, they then selected the Cobra Jet’s dual 65mm throttle body [PN M-9926-CJ65], which delivers substantially more air than the single 80mm piece found as original equipment on the BOSS and helps to fill the CJ intake manifold. The last item in this first step of the equation was to finish off the improved inlet tract with one of their cold air kits [PN M-9603-M50CJ] and develop an engine calibration to work with the improved airflow. The end result on the dyno was 29 additional horsepower and 10 foot-pounds of torque.

They weren’t finished, though – Step 2 dug a bit deeper into the engine, replacing the camshafts on both intake and exhaust valves with the M-6550-M50BINT and M-6550-M50BEXH pieces right from the Ford Racing Parts catalog. The intake camshaft has 13mm of lift and 263 degrees of duration, 1mm and 3 degrees more than the factory BOSS Camshafts. The exhaust cams carry 13mm lift and 290 degrees of duration, which is a substantial upfit from the factory 12mm/263 degree duration BOSS exhaust camshaft. Another calibration was developed to take advantage of the airflow improvements and maintain the Variable Camshaft Timing designs’ benefits, and the dyno was rolled to a 49 hp increase, with 15 ft-lbs of torque over the stock BOSS 302 designs.

The last step in the equation was a set of 1 7/8-inch tuned long-tube headers [PN MST-CY78NC], which replace the factory “shorty” design and provide even more benefits. As the old saying goes, more air in, more air out – and more power on the dyno. The headers fed into a set of unrestricted straight pipes and finished off the modifications by adding 19 more horsepower and 8 foot-pounds of torque, for an overall gain with the proper engine calibrations of 68 hp and 23 ft-lbs of torque, without ever unbolting a cylinder head or adding nitrous or boost.

Our friends at Ford Racing say that the changes keep the Ultimate BOSS civilized and drivable – so if you’re looking for improvements, maybe it’s time to look in this direction. Check out the Ford Racing Parts website for more information on the individual parts and pieces used to build the Ultimate BOSS.