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Long term Hellcat: Smiles per gallon and improved grip

by Patrick Rall on

In the latest installation of my long term review of the 2017 Dodge Challenger SRT Hellcat, Im going to talk about how much I love the car, but this car doesn’t just make me smile. My supercharged Challenger is constantly bringing happiness to other people around the car, from people on the sidewalk to people in traffic to random people who stop me during the course of my daily routine to talk about my Go Mango muscle car.

Smiles Per Gallon

As you might imagine, driving the 2017 Dodge Challenger SRT Hellcat every day never gets old. On nice days, being able to exercise all 707 horses with the stab of my right foot is an endless stream of fun. The combination of the supercharger whine and the exhaust note is sweeter than any sound coming from the Harman Kardon sound system, and you don’t always have to be going fast to love driving the Hellcat. Just cruising around town at the speed limit, the feel of piloting this hulking monster with the steady grumble from the rear is incredible. While the cars have changed a great deal since the 1970 Hemi Cuda was available in dealerships, the Hellcat Challenger offers the same primal feeling of mechanical power that you got with the original muscle cars – it just does it with a whole lot more power and a loaded cockpit.

The Hellcat Challenger is a blast to drive hard, but calm, everyday driving is almost as much fun. Driving to the grocery store or the post office means experiencing the feel of that Hemi rumbling through the chassis while the exhaust purrs loudly, so the 707-horsepower Dodge essentially makes everything more fun.

I got caught in traffic last week on a hot, rainy day and I quickly found that sitting in traffic in a Hellcat Challenger. With the windows up, the AC blasting, the cooled seats working their magic and the premium sound system booming, there is nothing more that I could ask for in a daily driver and while I hate traffic, there is no question that I am happier in my Hellcat in traffic than I am in something other than a Hellcat.

When cruising around town, a quick hit of the throttle effortlessly roasts the stock Pirelli tires and when driving around town with the supercharged Challenger, “light’em up” is a regular request from folks on the sidewalk. In fact, in my time driving the Hellcat Challenger, I have found that you get lots of comments from people everywhere you go. Here are just a few examples.

I picked up my kid from his high school last week and there was a large group of elementary school kids leaving the pool area and headed back to their school across the parking lot. As I sat there, waiting for my kid to come out of the school, literally dozens of elementary school kids offered their positive support for the car. Some yelled “nice car” and others spurred me to rev the engine – and I obliged. I could hear some of the kids talking – and we are talking about fairly young kids – yet I could hear that a few of them knew that it was a Hellcat car.

Two weeks back, I was sitting at a stop light when a guy pulled up next to me in an off-brand, V8-powered muscle car. I was ready to put bus lengths on him when he shouted out that he loved my car and he didn’t want to race, because he knew that I would smoke him. However, he still wanted to hear the big cat leave the line hard and once again, I obliged.

Next, on multiple occasions over the past month, I have come out of a store to see someone standing at my Dodge. In some cases, they tell me that they love the car and head on their way while others want to talk about the Hellcat Challenger. In seeing how much people are interested in the car, I am always happy to pop the hood and show off my supercharged Hemi, letting people snap pictures while we talk.

Finally, a local eatery that my wife and I frequent has parking right in front and huge garage doors that roll into the ceiling, effectively making the front an open-air restaurant. I like to go there, park in the front and sit towards the front. This allows me to keep an eye on my car, but I also see the reaction of the many people who walk and drive by the Hellcat. Even when there are other hot, new cars parked along the street, I never see people stop to check them out – yet it never fails that a half dozen or so people will stop to take pictures every time we eat there.

As much as my Hellcat Challenger makes me smile, I love the attention that it gets and I love the smiles that I am able to put on the faces of random people with a quick rev of the supercharged Hemi or a little spinning of the rear tires. It only gets about 25 miles per gallon on the highway, but it gets at least 200 smiles per gallon everywhere I go.

Improved Grip and Peace of Mind

This month, I also added another modification that adds a little performance and a little peace of mind. In the Hellcat community, it is not uncommon to read about owners breaking driveshafts and rear differentials, even in stock form. One of the few “problems” with the car in stock form is that on a hard launch, there can be a fair deal of dry-hopping with the rear tires. This happens because the rear differential is mounted to the floor with rubber mounts that help keep some of the vibration out of the chassis. When you launch the Hellcat too hard with the stock tires, those stock differential mounts flex, the differential wiggles around and you get wheel hop.

In the worst case situations, too much wheel hop will cause those rubber mounts to break and when that happens, all hell breaks loose under the car. In many cases, a failing differential can also damage the driveshaft and other components under the vehicle, but there is a component that can help prevent the rear differential from breaking while also reducing wheel hop. A simple differential brace bolts to the rear differential and the chassis of the car, adding extra reinforcement to the factory differential mounts while also helping to stabilize the rear differential.

All of the quickest and most-powerful Hellcat cars in the world run differential braces and while I have no plans to make my car that fast, I liked the idea of less wheel hop and less chances of breaking a differential, so I turned to the same company that provides the brace for the world’s nastiest Hellcat cars. That company is Per4mance Development and while there are other options on the market, I wanted to have the same piece on my car that the builders of the 8-second Hellcats trust for their high performance beasts.

 

Per4mance Development offers two different differential braces for the Dodge Challenger (and Charger) SRT Hellcat – the original unit and the new, “reduced clearance” unit. The slimmer unit is required for some aftermarket exhaust systems, so that is the one I picked for my own car and I got it in the same bright red as my Brembo brake calipers. It cost $189 – $20 more than the standard unit, but again, this is the piece that you want to get if you might ever change the exhaust system.

Installation Frustration

Installation of the piece was fairly easy once I took my time, but when I got the Per4mance brace, I put the car up on ramps and quickly started installing it. It is really as simple as removing two bolts from the rear differential, putting the bolts through the brace, putting the bolts back into the differential, adding a rubber spacer on top of the brace and running two bolts up into the chassis to secure the unit in place. That is it. Four bolts, a rubber spacer and the metal brace itself. When I finally got it installed, it took me less than 15 minutes to install.

Unfortunately, on my first attempt, I was rushing when trying to install the chassis bolts. The 2016 Challenger has a crossmember above the differential that has two threaded holes in the perfect place to mount the brace, but in my 2017 model, the holes are not threaded. This means that I had to put a nut on top of the bolt, inside of the chassis through a small hole next to where the bolt goes. I clumsily knocked the nut past the bolt and it rolled all of the way through that part of the chassis, down to where the control arm connects. There are gaps in the chassis that allowed me to see the nut, but the gaps are all far too small to pull the nut out. The only opening big enough to rescue the nut was the opening up by the brace –several feet from where the nut had come to rest. Of course, the nuts in the kit are specially crimped, so you can’t run out and buy the same thing, so I had to get that nut out of there.

I saved the nut by putting a small zip tie through an opening in the chassis and through the nut. I then took a long piece of stiff bailing twice with a different nut tied to the end and pushed that through the hole by the brace, fishing that twine through the chassis and down to where the nut had fallen. Once there, I was able to wrap the zip tie in the nut around the twine and I pulled it back up out.

Just as I got it out, it started to pour down rain and it was getting dark, so I removed the brace, tightened everything down and packed up for the day. I spent several hours under the car, swearing and throwing tools as I worked on a method to fish that nut back up out until I came up with my twice-and-zip tie method.

However, the next day, I planned ahead. Rather than just dropping the nut through the hole in the chassis and hoping to get the bolt through it, I used electrical tape across the top of a box wrench to hold the nut in place, directly over the bolt hole. Doing it this way, I had the brace installed in less than 15 minutes, so the moral of the story here is that if you have a 2017 Hellcat car, don’t drop your differential brace nut into the chassis, as it turns a 15 minute job into a several-hour-long battle under the car.

A Great Upgrade

I got the Per4mance Development differential brace mostly to help to prevent breaking the rear differential with the hopes that it would reduce wheel hop, but frankly, I am shocked at how much of a difference it makes. Wheel hop in almost every condition is reduced to almost nothing. In some rare cases, it will hop a bit, but I would say that it is cut back by 95% and when it does hop – it is far less violent than it was without the brace.

What I didn’t expect is that the car is much straighter and more sure-footed when the car loses traction. For example, when I would pull onto the street in front of my house and hammer the throttle without the brace, it would spin the tires and the back end would dance around with the flex of the rubber differential mounts. With the added support of the Per4mance brace that movement is prevented and as a result, the back end feels far more planted and the car stays much straighter as I work to get traction.

When I ordered my differential brace, a friend with a built Hellcat called it one of the best modifications any Hellcat owner can make and after putting 500 miles on the car with the brace, I agree wholeheartedly.  It doesn’t make the car any quicker or faster, but it adds peace of mind while also improving launching abilities in reducing wheel hop and rear differential movement.

Going forward, I don’t really have any plans other than enjoying my 707-horsepower Mopar machine as my daily driver – making me and people around me happy as the Hellcat spreads joy throughout the land.

Check out the other chapters of my 2017 Dodge Challenger SRT Hellcat long term review.

Long term test: 2017 Dodge Challenger SRT Hellcat
Long term Hellcat: Brutal break-in
Long term Hellcat: burnouts, lighting and other Demon gadgetry
Long term Hellcat: Ceramic coating
Long term Hellcat: Winter in Michigan
Long term Hellcat: Spring arrives with a popular mod and new plates

Patrick Rall was raised a Mopar boy, spending years racing a Dodge Mirada while working his way through college. After spending a few years post-college in the tax accounting field, Patrick made the jump to the world of journalism and his work has been published in magazines and websites around the world.

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