Dodge pulled out all the stops when they unleashed the 707-horsepower Challenger Hellcat onto the streets of America. It’s the undisputed king of muscle cars. But that lead is soon about to evaporate when Dodge’s new Demon takes the stage. Hellcat owners have watched from their comfortable perch as lesser cars and their owners have struggled to match the onslaught on the Hellcat’s boost—but the tables have turned. Hellcat owners will soon be grabbing for the parts catalog to fortify their kitties. Just know that Hooker is way ahead of you and has your back! Fortunately, the Hellcat powerplant lends itself to an unfettered freeflowing exhaust. The engineers at Hooker’s BlackHeart exhaust division wanted to know: how much more could they extract from the Hellcat’s already potent combination if they also took a no-holds-barred approach to the exhaust system? We’ll cut to the chase: They got an extra 55 hp peak to peak, and more than 50 lb-ft of torque through the entire powerband—and that’s at the rear wheels, kiddos!
It all started when we went to Hooker’s BlackHeart exhaust facility in Bowling Green, Kentucky to witness installation of their 1 7/8-inch long-tube headers and 3-inch header-back exhaust on a 2016 Hellcat. The BlackHeart headers feature hand-welded construction and formed, merge collectors with a scavenger spike that either connect to the OEM exhaust via special link pipes (sold separately), or in the case of our test, to Hooker’s BlackHeart header-back exhaust. Both the exhaust and headers are fashioned from lightweight 18-gauge 304 stainless steel tubing and set the industry standard for fit, finish, and in our estimation, sound quality too. (Make sure you check out our video!)
During the installation, it was clear that the Hooker BlackHeart development engineers did their homework. The headers fit perfectly, and the complete exhaust system tucked up nicely against the Hellcat’s belly without any fuss. Now check out the step-by-step action to see how you can close up the Demon horsepower gap on your new Hellcat.
Compare the Hooker BlackHeart 1 7/8 x 3-inch long-tube headers and link pipes to the stock Hellcat manifolds (top). Besides offering better breathing and exhaust scavenging, the BlackHeart system is nearly twenty pounds lighter than the factory SRT components.
The OE Hellcat exhaust (top) looks puny compared to Hooker’s BlackHeart header-back exhaust. It’s a wonder it supports 707 hp at all! The obvious difference is the change from an X-pipe in the OEM system to an H-pipe in the Hooker system. (The H-pipe offers a more muscular sound over an X-pipe.)
Hooker Development Engineer Doug Marino began the installation process by removing the factory catalysts.
To increase working room, Hooker R&D Technician Allen Pendley removed the steering shaft.
Here, Marino removed the starter motor to afford additional clearance.
Next, with a jack stand supporting the Hellcat’s engine, Pendley removed the engine mounts.
To reach all the OEM manifold fasteners, a long extension and 10mm swivel socket was essential. Marino and Pendley also used a ratchet strap to pull the engine to each side to ease access as well.
Pendley then removed the OEM manifolds from the bottom.
The Hooker BlackHeart 304 stainless steel long-tube headers feature tuned 1 7/8-inch primaries, 3-inch merge collectors, thick flanges, high-quality welds, and hand-blended ports. Three-inch link pipes are available that either connect to the OEM exhaust, or to Hooker’s 3-inch exhaust systems.
The craftsmanship on the BlackHeart headers is first-rate—just what the Hellcat’s supercharged Hemi needs to breathe better.
Pendley began installation by slipping the BlackHeart headers into position on each side.
Using a long extension and a 10mm swivel socket, Pendley tightened all the flange fasteners.
With the headers in place, Marino installed the link pipes that connect the Hookers to the OEM exhaust system.
The link pipes connect to the headers with a coupling clamp. This clamping system made for an easy, leak-free installation.
After double-checking the component alignment, Marino finished the header installation by tightening the clamps.
The Hooker BlackHeart long-tube headers tucked up closely to the chassis and fit like a glove.
We could’ve stopped there, but because we were looking for maximum power gains, we opted to install Hooker’s BlackHeart race-only header-back exhaust system. We started by disconnecting the active exhaust valve actuators and exhaust clamps.
The Hooker system retains the OEM exhaust tips, so Marino removed them and set them aside.
With everything disconnected, we removed the OEM exhaust system as one piece.
The Hooker BlackHeart exhaust system features minimal bends and 3-inch, 18-guage 304 stainless steel tubing for maximum flow, durability, and light weight.
Even though the Hooker system doesn’t use exhaust valves, the OEM actuators are attached to mounts on the tailpipes to keep the Hellcat’s PCM happy.
Marino swapped over the appropriate header link pipes for the 3-inch Hooker exhaust using the supplied coupling clamps.
Marino continued by connecting the BlackHeart H-pipe to the link pipes using the supplied clamps.
Next, the Marino slipped the mufflers over the ends of the H-pipe.
With the mufflers in place, Marino installed the tailpipes into the mufflers.
Marino installed the resonators over the tailpipes.
For a sleeper look, the Hooker BlackHeart system uses the (already handsome!) OEM exhaust tips.
With all the tubing in place, Marino aligned the system and tightened the clamps.
The complete Hooker BlackHeart exhaust system is a work of art under the Hellcat’s well-engineered underside.
The Hooker BlackHeart long-tube headers require a PCM tune for maximum performance, but the factory PCMs on 2015-’16 Chrysler products cannot be tuned. Fortunately, DiabloSport offers a solution that includes an “unlocked” PCM. Marino swapped the factory PCM with the DiabloSport PCM.
With the DiabloSport PCM installed, Marino then installed a tune compatible with the Hooker BlackHeart long-tube headers using the supplied inTune i2 Performance Programmer.
The Hooker BlackHeart headers and header-back exhaust transformed the Hellcat’s persona from “raspy alley cat” to “growling panther.”
With wrenching done, Marino strapped the Hellcat to Hooker’s in-house DynoJet dynamometer. There, the Hooker BlackHeart headers, exhaust, and DiabloSport tune picked up 55 horsepower peak-to-peak, and a very fat torque gain across the rpm range!
ORIGINALLY PUBLISHED ON JANUARY 30, 2017 BY WES DUENKEL