Long On Power

After the short-tube testing, we stood down for a couple of days waiting for the first set of long-tube headers to emerge from BBK's prototype shop. But then the testing shifted into Fifth gear, with a new baseline set with the car returned to totally stock condition. This time the baseline figures came in almost square, the horsepower at 360 and the torque at 361 Ib-ft.

Because the long-tube headers can't be run with the stock H-pipe, the long-tube test setup was simple—the long-tubes and their matching X-shape crossover pipe. So Mike Briggs, BBK's lead prototype tech and media liaison specialist got to pull the stock headers off for the umpteenth time and the long-tubes went on.

When the tires stopped singing on the rollers, the power had jumped which naturally fell at rpm points not shown in our charts—were 391 hp and 367 Ib-ft of torque. Anyway you look at it, the BBK long-tubes gained at least 25—almost 30—horsepower. That's a solid gain you can feel from behind the wheel.

Furthermore, the torque muscled up far more than the measly 2 Ib-ft the peak would indicate. Looking at the full arc of the torque curve, it's clear the long-tubes add generous torque down low—about 34 extra Ib-ft at 3,000 rpm—but then the torque curve plunges back to the baseline values from 4,100 to 5,500 rpm. At 5,500 rpm, the torque shoots right back to where it would have been had it not taken its midrange dip.

Two things are notable about this torque dip. First, its unfortunate, intentional-by-Ford placement falls right across the Coyote's torque plateau, robbing it of a higher peak value. Secondly, the midrange dip is likely a result of Ford's engine management software getting its tentacles around the ignition timing or electronic throttle in order to calm the party. One wonders what ecstasies await with electronic tuning.

Finally, because the prototype cold-air intake was busy posing as a pattern for its production tooling, we were unable to test it with the long-tube headers.

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