On The Dyno

i II of the BBK parts made more power, especially the long-tube headers, and as we all know, the stock 5.0 makes a ton of power with no mods whatsoever. To be more specific, the stone-stock 5.0 put out 362 rwhp. That's nominally 150 hp more than the Coyote's pushrod namesake, and more than 100 additional horsepower compared to the previous Three-Valve 4.6 engine.

But before we get any further into the hard K -HB numbers from the BBK test, let's recall that E; :jgc as with most chassis dyno testing where the R ,'AB| engine management computer is still in com- ¡|* TjjMÉ píete control, important variables such as igni- F^ ** tion timing are changing, mainly in response 9| ínRi to rising engine temperatures. Thus, these are |S WjS£-relatively casual dyno tests, so look for the P'i^ff general trends and try not to get hung up on a M| B couple of horsepower here and there. E

Furthermore, you must not compare our B jP* short-tube header figures directly to the long- BÚHE tube results because the two were tested differently (see the sidebar Fourth vs. Fifth Gear). The short-tube results were taken from tests run in Fourth gear and thus are lower than the long-tube tests that were run in Fifth gear.

With that said, bolting on the BBK short-tubes showed they gave a substantial gain in torque below the torque peak, but at the midrange they lay down flat, before picking up 2 hp again around the horsepower peak. The dip is likely the engine management curtailing torque, but the short-tubes did worse than the long-tubes in the midrange, so there is something in the tube length as well.

A bigger, more established change came by adding BBK's X-shape crossover pipe to the end of the short-

tube headers. This gave a gentle but definite lift up across the tach, but especially north of 3,500 rpm. The power peak reached 368 hp and 351 Ib-ft of torque and in general the combination of short tubes, X-pipe seem to be worth 5 hp and 3 Ib-ft over just the short-tubes in our test.

The final test in conjunction with the short-tube headers was BBK's prototype cold-air intake. This was definitely a happy rpm addition, building power starting at 3,500 rpm, but with authority from 5,000 rpm to the power peak, where it added a solid 7 hp to the party. And, as you'd expect, it gave a big throaty roar in the process.

All told, the combination of short-tube headers, catalytic X-shape crossover, and cold-air inlet was worth just shy of 12 hp and about 8 Ib-ft of torque at the peak compared to the stock baseline. Remember, too, that this is measured with the transmission in Fourth gear; the same tests in Fifth gear would add a horsepower or two, and an easy 10 Ib-ft of torque.

Short-tub«

Difference

Short-tub«

Difference

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