Kristian Grimsland
Associate Editor, Muscle Mustangs & Fast Fords
December 17, 2013
Photos By: Marc Christ

If you've been following us on Facebook, Twitter, and Instagram, you'll know our '85 Coyote coupe project has finally made it onto solid ground. If you haven't, well, all we can say is you're missing out.

It now has new paint, Weld RT-S wheels, massive Wilwood brakes, a new interior, and an incredible Kenny Brown suspension. Little by little, we've been installing all the necessary systems.

In this issue, we turn our attention to installing BBK Performance long-tube headers for Coyote swapped Fox-bodies and SN-95 Mustangs (PN 16340, $749). We also received an X-style mid-pipe featuring high-flow catalytic converters (PN 1786, $479). But the highlight of this exhaust system is BBK's all-new Varitune mufflers.

"For years, Mustang enthusiasts have made trade-offs when it comes to picking a performance muffler or axle-back exhaust," explained Brian Murphy, owner of BBK Performance. "Utilizing our 25 years of experience as one of the best known and largest performance brands for aftermarket Mustang exhaust and induction upgrades, our research and design team set out to build a performance muffler that would give enthusiasts the best of both worlds.

"With the Varitune muffler, a 3-inch internal power valve allows enthusiasts to adjust the sound and performance levels with the simple twist of a wrench. This new technology allows you to literally go from a mellow-but-throaty, three-chamber design, to a more radical and even higher-flowing, straight-through design in just minutes."

BBK Varitune mufflers are available in either aluminized or stainless steel, and sell for $109 to $129 each depending on size. A full line of after-cat Varitune systems will hit the market shelves in late 2013.

We haven't fired the ol' coupe up yet, but there's no doubt it's going to sound wicked. We'll be sure to update you with how well these new mufflers adjust, and how quiet and loud they can get.

We decided upon BBK Performance’s full exhaust system designed for Fox-body and SN-95 Mustangs that feature a 5.0L Coyote engine.
Due to the width of the 5.0L, we needed to lower the K-member in order to fit the long-tube headers. When dropping the K-member, make sure to properly support the engine. We used a polejack positioned on the edge of the oil pan.
1. Performance Automatic supplied us with a Mini/High Torque starter (PN 1910, $149). Before installing the headers, we made sure to fit and install the starter.
2. BBK’s Coyote swap headers (PN 16340, $749) are mandrel-bent and feature 13/4-inch tubing with 3-inch collectors. Headers are available in chrome or silver ceramic coat.
3. Here you can see the headers going in. Removal of the steering shaft is necessary for the driver side.
4. All necessary hardware is included with the headers. Tighten the eight nuts per header to properly secure the headers in place, using a wrench or socket.
5. Install the two studs per header onto its appropriate collector flange.
6. BBK also supplied us with a 3-inch, X-style mid-pipe featuring high-flow catalytic converters (PN 1786, $479).
7. Due to the extensive customization of our build, certain parts needed to be modified in order to fit. We needed to shave part of the crossmember in order to properly fit the X-style mid-pipe.
8. Associate Editor Marc Christ and your author fitted the X-style mid-pipe.
9a. BBK Performance has recently released its all-new Varitune mufflers for late-model Mustangs.
9b. Its new mufflers are fully adjustable thanks to a unique power valve, allowing users to adjust sound levels.
9c. Adjust inward for a quieter sound, and outward for a louder one.
10. Here, Christ fits and installs the new mufflers. BBK includes an assortment of clamps and hangers to properly mount the mufflers.
11. Christ also helped install the over-axle pipes and tailpipes. Using the L-brackets, we secured the tailpipes to the rubber exhaust hangers behind the rear bumper.
12. A pair of oxygen sensors was included in our Ford Racing Performance Parts control pack kit.