Do you want to go fast? Then it’s time to get a supercharged Hellcat Challenger. Do you want your Hellcat to go faster? Then the time has come for some well-chosen aftermarket performance components and a professional tune to take advantage of the parts. Still not enough? How would you like to own and drive the fastest Hellcat on the face of the earth? If you would, then you need a GRMPYCAT.
What is a GRMPYCAT? It is truly the fastest and quickest Hellcat in the world. For the past three years, owner and driver Kevin Helmick has placed his Challenger under the knife to transform it into a race vehicle. During the 2021 Holley MoParty event, Helmick pushed the GRMPYCAT Challenger to a world record quarter-mile elapsed time of 7.019 at 199.46 mph.
Above Left: Kevin Helmick started with a 2016 stock Hellcat Challenger, but he has been a man on a mission. Above Right: The last few years have seen the Challenger break into the nine-, eight-, and finally the seven-second zone. The Challenger is now the fastest and quickest Hellcat on the planet, posting a 7.019 elapsed time at 199.46 mph.
Helmick’s story started well before the introduction of the Dodge Hellcat models. As a teenager, he enjoyed building and wrenching on cars, and his passion ran deep for the Pontiac products. However, when he graduated high school, he started a career serving his country, and his days working on cars ended.
The story could have ended there, but just a little over four years ago, Helmick purchased a Hellcat SRT Challenger for his son, Tanner. Helmick had an opportunity to drive the Hellcat Challenger, and that innocent ride brought back a flood of emotions. A decision was quickly made; Helmick needed to have a Hellcat of his own. A black 2016 Hellcat Challenger was located at Whitten Brothers Chrysler Jeep Dodge Ram in Richmond, VA.
Above Left: The Hellcat has a stroked 426 Gen 3 Hemi sporting a 98mm Jose turbo, eight Atomizer 850 lb. injectors, and three Atomizer 400 lb. injectors in the cold pipe. Above Right: Helmick has been on a mission with the GRMPYCAT, and it has led him through plenty of engine and driveline combinations until he and his crew hit upon the current setup.
At first, Helmick took the Hellcat to the track and raced with the others running Challengers and Chargers. With a goal of dropping the Challenger into the nine-second zone, Helmick, like many others, added bolt-on parts and made PCM and software upgrades. Helmick managed to collect several nine-second timeslips. By 2019, he got the urge to drop the Hellcat into the sevens.
Helmick worked with Jason Brazzel of Brazzel Performance Fabrication. The goal was to drop the Challenger’s weight while adding a roll cage and strength to the chassis. The chassis weight eventually dropped to nearly 3000lbs., which was a substantial weight reduction. In addition, the chassis was finally built to the SFI-25.2 standard. In the meantime, with the reduced weight and a new ATI Turbo Hydromatic 400 transmission, trans brake, and a Neal Chance converter, the Challenger dropped into the eight-second zone in 2020.
Above Left: The Challenger has a custom 4-link rear suspension, strange aluminum brakes on the rear, an all-carbon interior, Bogart Racing rear wheels with M/T 315 ET Street Pro Drag Radials, and a Strange Ultrafab 9 with 9.5 pro gear 4.11:1 ratio. Above Right: On the front of the GRMPYCAT are Strange spindles and carbon fiber brakes, a Red River steering rack, and Weld V-Series front wheels with M/T tires.
As the carnage of broken parts began to grow, Demon Performance engine builder Sujal Patel and TKM tuner, “the” Kevin Mullins, arrived at a perfect combination that dropped the Challenger solidly into the seven-second zone. The engine is a stroked 426 GEN3 Hemi with a 98mm Jose turbo. The crankshaft is by Winberg, and it swings Diamond pistons hung on GRP rods.
Above Left: Helmick keeps track of his accomplishments, and he lets the entire world know he has the fastest and quickest Challenger by posting it on his trailer. Above Right: A timeslip hides nothing. The Challenger ran a 1.152 second 60-foot, 162.7 mph at the eighth, and the record elapsed time and mph are displayed at the bottom of the slip.
The Thitek cylinder heads are ported and fitted with Victory titanium valves and Manton rockers arms actuated by Trend one-piece pushrods and Johnson lifters, riding on a custom ground camshaft. Fuel is plumbed into the Hemi via eight Billet Atomizer 850 lb. injectors with an additional three Atomizer 400 lb. injectors located in the turbo cold pipe. A 26 GPM Sid Waterman fuel pump and a Holley Dominator throttle body rounded out the fuel system. The engine and chassis modifications are extensive, so a list has been assembled and detailed further below.
Above: A professional rig, which includes a truck and a fully loaded trailer are necessary to keep a car nearly as quick as a Pro Stocker on the track. Helmick’s rig, just like the GRMPYCAT, is state-of-the-art.
When we asked Helmick about any suggestions he has for racers looking to improve their stock or lightly modified Hellcat, he stated, “Keep it on the strip! Set goals. Think about where you want to be and build to it. If it’s not FUN, it’s not worth doing!” While you may not build a Hellcat as radical as the GRMPYCAT, you can take Helmick’s advice and have fun with what you have; he certainly has fun with his.
Check out Helmick’s GRMPYCAT running a 7.01 in the quarter-mile.
A Seven-Second Hellcat Recipe
CUSTOM 25.2 chassis
426 stroked Gen 3 HEMI
98mm Jose turbo
Diamond pistons
Eight Atomizer 850 lb. injectors
Three Atomizer 400 lb. injectors in the cold pipe
Winberg crank
Thitek ported heads
GRP connecting rods
Custom ground cam
Victory titanium valves
Manton rocker arms
Trend one-piece pushrods
Johnson lifters
Waterman 26 GPM fuel pump
Peterson external oil pump
Milodon oil pan
Menscer 4-way adjustable shocks
Strange spindle
Strange carbon fiber brakes
Red River steering rack
ATI big shaft full T400
Moroso pan
Neal Chance converter
Trans brake
Holley Dominator
PST carbon fiber driveshaft
Dual Stroud pneumatic chutes
Stroud fire suppression system
M&M shifter
Davis technologies VPS, Profiler
Cool shirt air system/water system
MSD600
Smart wire
Custom 4-link
Strange aluminum brakes on rear end
All carbon interior
Weld V-Series front wheels with M/T tires
Bogart Racing rear wheels with M/T 315 ET Street Pro Drag Radials
Strange Ultrafab 9 with 9.5 pro gear 4.11:1 ratio