A great many owners of Hellcat-powered vehicles from Dodge and Jeep have learned that swapping to a smaller pulley adds gobs of power (with the necessary supporting modifications). The problem with the pulley swap options on the market over the past few years is that they lack the internal decoupling and isolating assembly found in the stock Hellcat supercharger pulley, but that has just changed.

Litens High Performance – a division of the same Canadian firm that produces the stock supercharger pulley for the Hellcat Challenger, the Hellcat Charger, the Trackhawk, the Hellcat Redeye and the Demon – recently introduced the first decoupling pulley for the IHI superchargers on the modern Mopar monsters and it has a fitting name.

The HellRaiser.

The HellRaiser pulley is produced by Litens High Performance and distributed by Tendeco to performance shops around North America. This pulley measures 2.72-inches and features the same basic structural design and the same internal decoupling design as the stock pulleys, but those stock pulleys are 3.43-inches (87mm). Where the stock pulley on the Hellcat cars and the Trackhawk deliver around 11 pounds of boost, the HellRaiser increases the boost pressure to 16psi.

For those who aren’t sure, an increase of boost pressure of 5psi is significant. Enough so that with a “conservative” engine tune, the HellRaiser pulley on a Hellcat engine yields around 780 horsepower at the wheels on 93-octane pump gas. When you step up to race gas and an appropriate tune, the wheel horsepower climbs to 900.

Figure that my 2017 Hellcat Challenger made 644 rear wheel horsepower, so based on the numbers above, the HellRaiser pulley with a pump gas tune would add around 135 horsepower at the rear wheels while a race gas tune (100+ octane) adds around 250 wheel horsepower.

Those numbers may vary based on location, air conditions and the actual dyno, but they were achieved with nothing more than the HellRaiser pulley, a set of fuel injectors from the 2018 SRT Demon and a conservative engine tune.

Development Details

For those wondering, the HellRaiser pulley from Litens High Performance was developed with some very well-known members of the Mopar Performance community. Rob Laing of Litens High Performance, a drag racer himself, Litens’ design team, John Lussier of Tendeco presented Hellcat and Demon owner Paul Georges with the idea. Testing was done throughout the summer by High Horse Performance, AJ Berge from HemiTuner Performance and CJR Performance to confirm the performance and function. The final result was a cooperation by everyone involved to bring this product to market but more importantly, they made sure that the pulley worked as planned.

Working with racers in the US and Canada, the HellRaiser pulley has already been heavily tested on the track and the dyno, and the results are nothing short of impressive. Hellcat Challengers and Chargers with minimal other modifications beyond wheels and tires have used the HellRaiser to get into the 9-second range while still being able to comfortably drive the car on the street.

In addition to adding big power, the HellRaiser pulley is much easier on the supercharger than the other popular pulley upgrades on the market due to the OE DNA in the decoupling assembly. Many Hellcat owners have found that swapping to a non-decoupling pulley can cause belt slip or the lower pulley to spin on the crankshaft, forcing those folks to pin the crankshaft. While pinning the crankshaft is always a good idea when building up your Hellcat Hemi, the decoupler in the HellRaiser removes the added stress to the lower pulley. Along the same lines, the decoupling setup provides less stress to the supercharger to keep big power as the main attraction.

Buying a HellRaiser

The HellRaiser has just hit the market as the only decoupling/isolating Hellcat pulley on the market and right now, there are only a few distributors, but they are some of the best-known names in the modern Mopar world. You or your tuning shop can buy the HellRaiser Pulley Kit (including HellRaiser Pulley, high performance Bando belt, dust cap and installation tool) from High Horse Performance or Hemituner Performance in the USA while Canadian buyers can order the Kit from CJR Performance, with an MSRP of $666.00 US or $849.00 Canadian

Again, actual power gains will vary, but for Hellcat owners who want the function and security of the stock decoupling pulley, HellRaiser is the answer.