If you're wondering will a hellcat supercharger fit on a 5.7 hemi, you're definitely not alone in that rabbit hole. It's one of the most common questions in the Mopar community, mostly because used Hellcat blowers are surprisingly affordable on the second-hand market. You see a 6.2L IHI supercharger for sale on Facebook Marketplace for a fraction of the cost of a brand-new Whipple or ProCharger, and suddenly, those dreams of 600+ horsepower start feeling a lot more realistic.
But as with anything involving high-performance car mods, the answer is a bit of a "yes, but." Yes, you can absolutely bolt that big hunk of aluminum onto your 5.7 Eagle or Pre-Eagle engine, but it isn't a weekend project where you just turn a few bolts and call it a day. It takes a specific set of parts, a decent amount of patience, and a very clear understanding of what your engine can actually handle before it decides to exit the chat in a cloud of smoke.
The physical challenge of the swap
Let's get the obvious part out of the way first: the 5.7 Hemi and the 6.2 Hellcat engine share some DNA, but they aren't identical twins. The intake ports on a 5.7 don't line up perfectly with the discharge ports on a Hellcat supercharger. If you try to just set the blower on top of the block, you'll see right away that things aren't going to seal up.
To fix this, you're going to need adapter plates. There are a few companies out there making these specifically for this swap. These plates bridge the gap between the 5.7 cylinder heads and the Hellcat blower housing. Without them, you've got zero chance. You also have to consider the height. The Hellcat blower is tall. If you're putting this in a Challenger or a Charger, you might need to look at hood clearance or aftermarket motor mounts to drop the engine a hair. If it's going into a Ram 1500, you usually have a bit more room to breathe, but it's still something to measure twice before you commit.
Why the ring gap matters more than you think
This is the part that catches most people off guard. If you're asking will a hellcat supercharger fit on a 5.7 hemi, you probably care more about the "can I do it" than the "should I do it," but we need to talk about your piston rings.
The 5.7 Hemi is a great engine, but it wasn't designed for double-digit boost. Specifically, the top piston ring gap is very tight from the factory. When you cram a bunch of boost into the cylinders, things get hot. When things get hot, metal expands. If that ring expands so much that the ends touch, it's going to pop the top of your piston right off. That's what Mopar guys call "the ring land failure."
To do this swap safely, a lot of guys will actually pull the pistons out and "gap" the rings for boost. If you don't want to tear the engine down that far, you have to be extremely careful with your tune and your boost levels. Most people suggest staying under 6 or 7 pounds of boost on a stock bottom end 5.7 if you want it to live for more than a few highway pulls.
The shopping list of support parts
You can't just buy the blower and call it a day. The supercharger is just the air pump; you still need a way to feed it fuel and keep it cool. Here is the stuff that usually adds up and makes the "cheap" Hellcat blower swap more expensive than people realize:
- Fuel Injectors: Your stock 5.7 injectors will be maxed out before you even leave the driveway. You'll need at least Hellcat injectors or something around 650cc to keep up with the new airflow.
- Fuel Pump: Depending on your power goals, the stock pump might struggle. A Boost-A-Pump or a drop-in 342 or 450 LPH pump is usually on the menu.
- Intercooler System: The Hellcat blower has internal intercoolers (bricks). You need a way to circulate coolant through them. This means an electric water pump, a reservoir, and a heat exchanger (basically a small radiator) that sits behind your grille.
- FEAD (Front End Accessory Drive): This is a big one. You need a way to spin the blower. You'll need a custom pulley setup or an adapter kit that lets the 5.7 belt system drive the Hellcat snout. Some guys swap over to a dedicated 10-pin or 8-pin setup to avoid belt slip.
Tuning and electronics
Once everything is bolted down, you've got to tell the computer what's going on. Your stock MAP (Manifold Absolute Pressure) sensor can't read boost; it only knows vacuum. You'll need to swap in a 2-bar or 3-bar MAP sensor so the ECU understands that there is positive pressure in the manifold.
Then there's the actual tune. Don't even think about trying to drive the car on the stock 5.7 map. You'll lean out and melt a piston before you hit the end of the block. You'll need a custom tune from someone who knows Hemis inside and out. Since 2015+ Mopars have locked PCMs, you'll also need to make sure yours is unlocked so your tuner can actually get in there and change the parameters.
Is it actually worth the hassle?
When you add up the cost of the used blower, the adapter plates, the cooling system, the fuel upgrades, and the tune, you're usually looking at a few thousand dollars. At that point, some people start wondering if a dedicated aftermarket kit like an Edelbrock E-Force or a Magnuson would have been easier.
Those kits are designed specifically for the 5.7, so they come with every single nut, bolt, and hose you need. They also usually fit under the stock hood without any drama. However, there is something undeniably cool about popping the hood and seeing that "Hellcat" logo staring back at people. It has a factory-plus look that aftermarket kits sometimes lack.
If you're a DIYer who loves hunting for deals and doing your own fabrication, then yes, the Hellcat swap is a blast. If you're paying a shop to do all the work, the labor costs might make a standard aftermarket kit a smarter financial move.
Final thoughts on the swap
So, will a hellcat supercharger fit on a 5.7 hemi? It sure will, and it makes for one hell of a sleeper. There's nothing quite like the whine of an IHI blower coming from a car that "shouldn't" have one. Just keep in mind that you're building a custom setup. It's going to require some tweaking, some troubleshooting, and a very light foot until you get that tune dialed in.
If you decide to go for it, just remember: keep the boost low, keep the fuel high, and make sure your cooling system is up to the task. If you do those three things, your 5.7 will handle the Hellcat heart transplant just fine, and you'll have a smile on your face every time you hit the gas and hear that blower scream. It's a lot of work, but for the Mopar enthusiast who wants something a little different, it's one of the coolest projects you can take on in your garage.