Thanks to a previously installed JLT cold-air system, Kurt Schutt's '11 Mustang GT stomped down an impressive 395 horses at the feet during the baseline-dyno portion of our exercise. That's par for the course among Coyote 'Stangs that have this mod.
With the 400-horse plateau in sight and MBRP's long-tube headers and complete exhaust system installed on the GT, the car was once again loaded on the Dynojet chassis dyno at GTR High Performance, so we could determine how much power and torque a freer exhaust will manifest.
As you see in the data from the "after" run, horsepower and torque show nice increases, as power is solidly into the 400s and the long-tubes yielded enough additional grunt to definitely get your attention. (Before you California readers get excited, none of the pieces we installed are CARB-approved/California-legal.)
A wide-open exhaust passage, using MBRP's non-catalytic H-pipe (PN S7236409; $418.95) and Race Series cat back set (PN S7226409; $901.95) should offer an estimated 20 more horsepower and 25-plus lb-ft of torque beyond the numbers we achieved with Kurt's naturally aspirated, CAI-only 'Stang.