Tech Talk: Chevrolet Corvette C8 xMOD Series Exhaust System

DESIGN CONSIDERATIONS

When it came time to develop one of our premium xMOD performance exhaust systems for the new 2020-2022 Chevrolet Corvette C8, there were numerous key factors to take into consideration. MagnaFlow has experience developing exhaust systems for prior iterations of the Corvette, but this time things would be a bit different. For one thing, the new Corvette features a mid-engine layout, which is quite a rare thing in a vehicle with a starting price well below $100,000.

3D Scanning

The first thing we decided to do was have the entire C8 3D scanned in order to get a feel for exactly what we were dealing with. One fact that immediately became apparent is the fit and finish quality on the new Corvette C8. Everything we scanned seemed to be built to very high tolerances and precise fitment requirements. By 3D scanning the entire vehicle we were able to make sure that the system fits precisely, without need for alteration or adjustments.

System Layout

The stainless-steel system consists of 3” diameter tubing leading to a crossover Tru-X pipe and then on to electronically actuated dual mode exhaust valves. From here exhaust flows into either muffler or xTreme Delete straight pipe modules before heading for the quad-split exit 4.5” tips finished in either polished stainless steel or black chrome. The systems are each produced using CNC precision robotic manufacturing and are covered by a limited lifetime production warranty and one-year finish warranty. Each aspect of the system has been designed with performance, aesthetics and heat management in mind.

WHY XMOD?

Modularity

One major factor that MagnaFlow’s xMOD series has going for it is the unmatched modularity it offers. Choose from among our available xMOD modules and swap between them to match your mood.

Planning on spending a day at the track? Go with the xTreme Delete straight pipe modules to hear that pushrod 6.2L V8 in all its unrestrained glory. Check local noise restrictions beforehand to ensure compliance.

Need a more comfortable exhaust soundtrack to cruise the streets to? Check out our xMOD C8 muffler modules for a tamer (although still plenty loud) experience.

One of the coolest features of this new xMOD system for the C8 is that we’ve been able to integrate our exhaust system with the dual-mode exhaust included in the Corvette’s optional Z51 Performance Package. This enables drivers to have the flexibility to toggle between two exhaust modes. One mode of these actuated valves is designed for quiet operation and perfect for when some degree of subtlety is desired, such as when leaving the driveway on a sleepy morning. The other option is perfect for when you want your presence to be known, such as when rolling on the throttle or enjoying a track day. It’s worth noting that MagnaFlow’s xMOD system for the Corvette C8 is designed to work on both models with and without the dual mode exhaust option.

No Drone Technology

Like other MagnaFlow exhaust products, this xMOD system for the C8 utilizes the latest NDT (No Drone Technology) developments to allow you to enjoy all the supercar-beating performance of the ‘Vette without having to deal with the obnoxious droning noises that can accompany other aftermarket exhausts.

In the case of this exhaust system NDT chambers have been integrated into each of the two straight-through unpacked mufflers. NDT is also incorporated into the design of the xTreme Delete straight pipe modules, meaning that drone shouldn’t be an issue no matter which modules you choose to go with on any given day.

RETAINING THE FACTORY ACTIVE EXHAUST

One of the awesome options available for the C8 and included in the Z51 Performance Package is GM’s dual mode performance exhaust. As mentioned above, this option gives owners the ability to cycle through several driving modes and settings in order to fine tune the performance exhaust to their liking and their situation.

Having had some experience working with active exhaust systems, the engineers at MagnaFlow worked hard to make sure that our xMOD system for the Corvette C8 retains this factory-installed feature. It took a lot of fine tuning and testing to get it functioning correctly, but this new MagnaFlow xMOD system now works seamlessly with the factory dual mode exhaust interface that’s connected directly to the car’s ECU (Engine Control Unit).

With a fully functional dual mode performance exhaust, you can now be as loud or as quiet as you want to be, whenever you want. At MagnaFlow our goal is to create the best exhaust system we can, with better performance and sound than a vehicle’s stock system. For the new Corvette that meant getting the factory active exhaust to work flawlessly with our xMOD system. Valve delete options are available for those C8 buyers that decide to not go with the factory dual mode exhaust, although all indications are that most purchasers chose the dual mode option.

DAYS OF DYNO AND TRACK TESTING

The extensive testing MagnaFlow engineers undertook to put the new xMOD system for the C8 through its paces was about more than just getting the dual mode exhaust system to work without a hitch. Such testing also served to determine how much of a performance improvement was gained by using our new system, as well as any issues that still needed to be worked out.

Performance Gains

The results of testing were promising. Engineers noticed max power gains of up to 18 hp and 17 lb. ft. of torque, as well as peak power gains of up to 12 hp and 13 lb. ft. of torque. That’s a significant improvement compared to the 5 hp and 5 lb. ft. of torque gained by running the factory dual mode exhaust. Our fans expect nothing less from an expertly designed xMOD performance exhaust system from MagnaFlow.

Feeling the Heat

One issue that came up during test was the considerable amount of heat produced by the naturally aspirated 6.2L LT2 V8. Such power in the Corvette’s tightly packaged engine bay created some challenges. This was exacerbated by the fact that the same air used to cool the engine compartment also needed to cool the brakes and other vehicle components while keeping the exhaust system at a reasonable temperature. Unlike vehicles with a  front engine layout where lengths of exhaust tubing located on the car’s exterior could help dissipate heat, the new mid-engine setup on the ‘Vette meant that all the heat sent from the engine through exhaust system would need to be managed within the small amount of distance between the engine and the exhaust tips. Another important reason for testing was making sure that none of the modifications made interfered with the existing high-end performance capabilities of the vehicle.

Testing revealed that the factory heatshields used for the stock system would be insufficient for our higher performing xMOD replacement exhaust. As mentioned before, this was in large part due to the already warmed, relatively slow-moving air that the system is forced by the car’s design to use to keep cool. In place of the insufficient factory heatshielding setup, we used custom-made, CNC-produced aluminum shielding in order to draw heat away from the exhaust system more quickly. We also worked directly with a company that specializes in heatshield technology in order to create three different heat wrap-style shields to protect vital system components: one wrap for the Tru-X pipe and two for the valve motor actuators. A set of these heat wraps is included with every C8 xMOD exhaust kit.

Multi-Metal Manufacturing

A lot of care and consideration went into choosing the materials for this exhaust kit. While the entire system is made of stainless steel, not all stainless steel is created equal. 304 stainless steel was used the most, due to the short overall length of this exhaust system and the fact that much of it would always be visible. This is because 304 stainless steel blues easily, which enhances the appearance of the system while mitigating surface oxidation. For this system the main piping, hanger brackets and exhaust tips are all made of 304 stainless steel. The muffler bodies use 436 stainless steel for its superior durability and resistance to blemishing, which is an important consideration for components as large and important as the system’s mufflers. 410 stainless steel is used for the brackets.

By utilizing a multi-metal design MagnaFlow is able to create a system where each material plays to its own strengths, instead of using a single grade of stainless steel as poor catch-all solution like you might find on other aftermarket performance exhaust systems. For example, a system made entirely out of 304 stainless would look as good as our system, but it wouldn’t be nearly as durable and would run into potential fitment issues due to the specific expansion properties of that grade of material.

THE PERFECT EXHAUST SYSTEM FOR YOUR NEW C8

If it wasn’t already apparent, the amount of intricate engineering, detailed planning and data gathering that went into the creation of this xMOD Corvette C8 performance exhaust system makes it the ultimate aftermarket exhaust upgrade for your new ‘Vette. At MagnaFlow we’ve taken the time to develop a system that both improves aesthetics and performs in such a way as to take full advantage of the engineering that GM put into creating its dual mode exhaust system. Whereas alternative systems on the market claim to “work with” the C8’s dual mode exhaust, they mostly do this by tricking the car’s ECU into thinking it’s operating valves when it actually isn’t. That compromise isn’t acceptable to MagnaFlow, so we made sure that our Corvette exhaust system would take full advantage of the existing dual mode setup. Our philosophy is that an exhaust system upgrade should be just that, an upgrade. No “upgrade” should take away existing performance features.

Now available for purchase! Interested in learning more about the MagnaFlow xMOD performance exhaust system for the 2020-2022 Chevrolet Corvette C8? Visit MagnaFlow.com for more details.

Have questions about our products? Give us a call at 1-800-990-0905, and we’d be happy to help.

EXPLORE xMOD SERIES FOR CORVETTE C8