If you're looking to squeeze more life out of your supercharger, a 2. 85 pulley hellcat setup is generally the particular first thing people talk about when they will want real, seat-of-the-pants power. It's that weirdly specific size that seems to sit right in the "sweet spot" for the majority of proprietors. It isn't therefore aggressive that you're constantly considering coming your engine upon a Tuesday morning drive to work, but it's certainly enough to make your neck strike the headrest a lot harder than the stock configuration actually could.
Let's be honest: the particular Hellcat is a beast right away from the showroom flooring. But as anybody who has ever owned a forced-induction car knows, the "stock" feeling dons off pretty fast. You receive used in order to the 707 horsepower (or 717, or even 797 depending on your year), and all of a sudden, you're scrolling through forums at two a. m. searching for more increase. That's where the 2. 85 pulley comes into play.
Precisely why the two. 85 dimension matters
When people discuss pulley swaps, they're really talking about physics. By shrinking the dimensions of the upper pulley on the supercharger, you're which makes it spin quicker relative to the engine's RPMs. Faster re-writing means more atmosphere, more air indicates more boost, plus more boost—if you have the fuel to back it up—means more energy.
The share Hellcat pulley is definitely about 3. thirty-five inches. Moving straight down to a 2. eighty-five pulley hellcat setup usually bumps your boost from the stock 11-ish psi as much as around 14 or 15 psi. This doesn't sound such as a huge jump upon paper, however in the world of Mopar, 3 or 4 pounds of boost is a game-changer. It's the difference between "wow, this car is usually fast" and "I need to create sure my insurance policy is paid up before I hit this on-ramp. "
You can't just "slap this on"
I realize a lot associated with guys purchase the pulley because it's relatively cheap—maybe a few 100 bucks—and think they're ready to proceed. Hang on a 2nd. If you simply put a 2. 85 pulley on the Hellcat without doing anything else, you're likely to have a very bad period. The car's pc won't know what regarding all that extra air, plus you'll likely operate lean, which is a quick track to needing a new motor.
To perform this right, you need a few things. First, you need the tune. Since 2015, these PCMs (Powertrain Control Modules) possess been locked down tighter than a drum. You'll need to get your PCM unlocked or even buy a revised one so the tuner can actually talk to the car.
After that there's the gasoline. Your stock injectors are great for stock power, but they start in order to sweat when you're pushing 15 psi. A lot of people jumping to a 2. 85 pulley hellcat build will get a set of 1050x or 1300x injectors. If you're planning on running E85—which you absolutely ought to if it's obtainable near you—those larger injectors are mandatory.
The feared "crank pin" discussion
If a person spend a few minutes in any Hellcat group, you'll hear someone mention pinning the particular crank. On a stock car, the harmonic balancer (the big pulley on the bottom) is just held upon by friction along with a bolt. It doesn't have a "keyway" or perhaps a slot to keep it from spinning on the crankshaft.
Whenever you include a smaller sized upper pulley such as the 2. eighty-five, you're putting much more tension and opposition on that belt system. There's a very real risk that the crank pulley will start to spin freely on the crank. If that happens, you're looking from an enormous repair expenses. It's a bit of a work to pin it—you need to get in generally there with a punch kit—but it's cheap insurance. Don't neglect this part. If you're doing a two. 85 pulley hellcat change, pin the turn. Period.
Dealing with the heat
More boost means more heat. It's just the way it is. The particular 2. 4L or 2. 7L IHI blowers on these types of cars are pretty efficient, but they do have their limits. When you begin spinning that motorized inflator faster with a two. 85 pulley, the air entering your engine gets warmer.
If the air gets too hot, the car's computer will draw timing to safeguard the engine, which means you shed the power a person just covered. This particular is why a person see Hellcat guys obsessing over "coolant chillers" or "spacer plates" and "thermal blankets. " With regard to a street vehicle that you just want to rip occasionally, you might be fine with the stock cooling, but if you're doing back-to-back drags or hitting the particular drag strip, you'll notice the car slowing down since the heat builds up.
Just how it feels at the rear of the wheel
This is the part everyone cares about. How does it actually feel?
A 2. 85 pulley hellcat feels such as the car finally woke up. The rpm hits much lower in the REVOLTION PER MINUTE range. Instead of waiting for the energy to build, it's just there the second you breathe on the particular throttle. The blower whine also gets a bit even louder, which is a nice little reward. You'll find yourself burning up through rear tires significantly faster, so I hope you have a budget for a few decent drag radials.
Upon the highway, the passing power is just stupid. You can be doing 60 mph, drop a few gears, and you're at triple digits before you can finish saying "Mopar or no car. " It transforms the Hellcat from the fast heavy vehicle into a vehicle that defies its own weight.
Reliability and every day driving
The particular question I get asked most is definitely, "Will this damage my car? "
Honestly, if you have got a good tuner and you don't go cheap upon the parts, the two. 85 pulley hellcat set up is incredibly dependable. There are guys with 50, 000+ miles on this exact setup who haven't had the single issue. These types of engines are overbuilt. The bottom end is stout, as well as the transmission (the ZF8) is one of the best in the business.
The primary "risk" isn't the engine blowing up—it's the belt slipping or snapping. You'll want to get a heavy-duty belt, like a Gates Green belt, to take care of the extra grasp needed for that smaller sized pulley. You might also want in order to consider an changeable idler pulley in order to make sure the particular belt has as much "wrap" around that 2. 85 pulley as possible. In the event that the belt slides, you lose increase, and it can make a mess associated with your engine bay.
Is it the correct choice for you?
You will find smaller sized pulleys on the market. A person could go along with a 2. 72 or maybe crazier. But when you go smaller sized than 2. eighty-five, the demands on your fuel program and your air conditioning skyrocket. You begin needing dual gasoline pumps and race gas or purely E85.
The 2. 85 pulley hellcat is the fact that perfect center ground. It's for the guy that wants to operate 10s at the particular track and then drive the kids to school with the particular A/C on. It's manageable. It's the "Stage 1" associated with the Hellcat world that actually provides a punch you are able to feel every individual day.
Just remember: it's a slippery incline. Once you sense what 15 pound-force per square inch seems like, you're probably going to begin looking at long-tube headers, then an consumption, then maybe a bigger blower completely. But as much as starting points go, you actually can't beat this particular setup. It gives the car the particular personality it should have had from the particular factory—unapologetic, loud, and incredibly fast.