5.0 Mustang & Super FordsHow To Engine
Recall: A New After-Cat Exhaust For More Horsepower
Squeezing In More Horsepower Via Ford's '99 Cobra Owner Notification Program
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All we wanted was a Mustang that could whip the pants off of an F-body. What we got was a Cobra with the same advertised horsepower as the Z28 and Trans Am, but quarter-mile times fell way short of what a 320-horse musclecar should run.
In our Oct. '99 issue, we were able to wring out a 13.79 at 100 mph with a brand-new '99 Cobra, but to run that number the entire air-filter assembly was removed and the valve covers, intake, and mass air meter were treated with bags of ice. Meanwhile, bone-stock F-bodies have been known to rip off low-13s without breaking a sweat, much to the chagrin of all Mustang owners and enthusiasts.
For the same article, our Cobra test car was strapped down for a few dyno pulls to verify the amount of horsepower making it to the rear wheels. With little break-in time and only 13 miles on the odometer, a first pull of 238.9 hp and 252.3 lb-ft of torque didn't translate into visions of seeing F-bodies in the rearview mirror. In the Cobra's defense, those numbers did increase to 266.6 and 285 respectively after thorough icing of the engine and removal of the air-filter assembly.
Once more people realized the Cobra was down on power they got on the phone to Ford SVT to request an answer to their power predicament. Their requests were heard and an Owner Notification Program, or an optional recall, was ordered. The answer to the problem came in the form of a new after-cat exhaust including revised mufflers, an Extrude Honed intake, and a reprogrammed EEC-V computer.
However, what kind of increase would the new components provide? To find out, we sat in on the rejuvenation of Richard Ringled's Cobra convertible. Before the installation of the new parts, Richard's Cobra belted out peaks of 265 hp at 6,000 rpm and 266 lb-ft of torque at 4,400 rpm on Dynamo Motorsports' Dynojet. Once the new components were installed, a return to Dynamo rewarded us with an increase of 17.2 hp and 15.7 lb-ft of torque. Factoring in a 15-percent horsepower loss figure, our before numbers (265 rwhp translates into 312 hp at the flywheel) were not far off the factory's 320hp rating. With the Ford-improved 282 hp at the rear wheels, that translates into roughly 330 hp at the flywheel, more than the factory rating. However, to truly put these numbers in perspective, we've heard of bone-stock F-bodies layin' down 280-290 hp at the rear wheels with the same factory 320hp rating.
It looks like Ford's improvements level the horsepower playing field, but for Cobra owners visiting the dragstrip there's still the predicament of finding a way to get it to the ground. Oh well, one thing at a time.
Not only did the new components boost horsepower on Richard Ringled's Cobra, fuel economy also improved from an average of 22 mpg up to 24 mpg--an improvement Richard is most happy about, since his daily-driven Cobra sees a round trip of 95 miles a day.