Review: Flowmaster Force II Cat Back Exhaust

Written by

CarParts.com Research Team

Automotive and Tech Writers

Updated on January 3rd, 2021

Reading Time: 6 minutes

Product: Flowmaster Force II Cat Back Exhaust
Vehicle: 2013 Dodge Charge RT – 5.7L HEMI V8
Owner/Reviewer: Stan Maloof

I had previously increased the air flow into the 5.7L HEMI with an intake system. Now it was time to provide a complimenting exit for that increase in air flow coming in and maximize the potential of the HEMI V8.

When looking for aftermarket parts for any of my cars, my first stop is always CarParts.com. Their user-friendly website allows me to search for parts specifically designed for my car. My intention was to buy an exhaust kit that I could install myself with my limited experience. What I learned though, was it’s often times better to allow those with the right tools and training to handle certain installs.

After entering my vehicle data into the CarParts.com website, I was presented with a choice of five exhaust kits designed specifically for my Charger. I chose a Flowmaster system for a couple of reasons. First, I hear a Flowmaster system on my neighbor’s car every day, and it sounds great. Also, the kit was priced considerably lower than the competitors’ kits. I chose the Force II system from Flowmaster rather than the American Thunder because I was looking for a subtle low tone that wasn’t too intrusive but would enhance the great HEMI sound. The Force II system claimed to fit the bill.

My Flowmaster kit arrived a short time after placing the order. The roughly 15″ X 16″ X 53″ box was neatly packed and included detailed instructions and great illustrations. After a quick read, I learned that a few welds were recommended in order to properly secure the system to the frame. I am not a welder, nor do I have a lift, so I decided to find a local shop that could perform the install for me.

I spoke with Kevin, owner of Kenny’s Muffler in Cypress, CA. He let me know his shop has installed several of these systems and mine could be done same day if needed and the total time involved would be approximately one hour at a cost of $150.00.

I arrived at Kenny’s Muffler a short time later and my car was immediately taken into one of their bays, no wait. The crew went to work right away and with obvious skill and confidence in the task at hand. I was instantly glad that I had chosen to seek professional help with this install. Having plenty of help is vital to ensuring a successful install. There are many points both during removal of the factory system and install of the Flowmaster kit that required helping hands to support parts until they were either freed from their housing or supported by their clamps. The crew at Kenny’s worked like a well trained team and their attention to detail was comforting to me as a customer.

Once the car was in the bay, the first step was to remove the two support brackets that secured the exhaust system’s H pipes to the frame. Next was the removal of all supporting clamps. These tasks were easily accomplished with a standard socket set accompanied by a handy extension tool.

During removal of the factory system, the team at Kenny’s Muffler noticed that only one of the factory outlets of the muffler was secured to the tail pipe assembly with a clamp. The passenger side (right pipe) however, ran straight through to the muffler. This required a cut through the pipe in order to remove it. Yet another reason I was glad chose to have the system professionally installed, rather than doing it myself.

Once the pipe was cut and clamps were removed, the entire factory system was easily removed and my Charger was ready for the Flowmaster kit.

The first step was to align the new Scavenger H-pipe with the factory header pipes and slide it into place. Once again, this step required a helper and tall jack stands to support the pipe as it was secured into place. Proper alignment is critical to an overall good fit and finish.

With the Scavenger pipe now in place, it was time to place clamps onto each of the muffler‘s outlets and slide each tail pipe into place. This was done using the factory mounted hangers and the fit was perfect. The instructions provided by Flowmaster required that all clamps remained tight enough to hold the pipes into position, but loose enough to allow for adjustment. This was good advice, as small adjustments at the header pipe and Scavenger pipe junction were required in order to allow for proper fit at the tail pipe connection to the muffler outlets.

After all of the pipes and clamps were fit into place, all clamps were securely tightened into place. As an added measure of security and commitment to quality, the kind folks at Kenny Muffler provided a 1” tack weld at each clamp in order to ensure system integrity and reduce chance for leaks.

Once the welds were applied and a quick test for leaks was performed, the install was complete.

While the install was taking place, I had a chance to ask Kevin about his thoughts on the Flowmaster kit I had purchased. He let me know that he installs several different kits each day and the Flowmaster is by far the most consistent and reliable when fitting the system into the factory spacing and mounts on vehicles. Kevin stated: “Not all kits fit the way they are supposed to. We often have to fabricate parts to make them work. That is rarely the case with Flowmaster”. He also pointed out that this kit is lighter in weight than the factory exhaust and the Flowmaster pipes have a larger diameter (2.5″ vs. the stock 2.25″). The lighter weight and the opportunity for more air to flow through the larger system both add up to increased performance from the HEMI.

As mentioned earlier in this post, my goal was to achieve a subtle low “rumble” from the HEMI. Something that would make it clear that there’s a HEMI V8 hiding under the hood, not too aggressive because it’s a daily driver for me and my family. The end result here was perfect. The low-end growl from the HEMI demands attention upon start-up and roars to life when the throttled up. I am very pleased with Flowmaster’s product and would highly recommend it for anyone looking to enhance the sound and performance from their engine.

Thanks again to Kevin and his crew at Kenny’s Muffler for a great install.

Any information provided on this Website is for informational purposes only and is not intended to replace consultation with a professional mechanic. The accuracy and timeliness of the information may change from the time of publication.