On this episode of Engine Masters, David Freiburger and company set out to determine if a 3-inch exhaust system will net a loss when compared to a 2.5-inch exhaust on a Chevrolet L98 V8 engine out of a third-gen Camaro, which makes about 350 horsepower. In addition, the fellas also find out if paying more for an expensive, quality muffler is worth the extra bucks.
In regards to piping diameter, the gang found that there is no power lost due to a “drop in back pressure”, meaning that the engine produced more or less the same amount of power with either exhaust system. IT wasn’t just peak power either, the power curves between the setups were nearly identical. For exact figures, see the specs below.
Note, a Magnaflow muffler was used for this series of testing:
- 2.5-inch exhaust: 399.6 lb-ft @ 3,400 rpm / 344.8 hp @ 5,100 rpm
- 3-inche exhaust: 399.9 lb-ft @ 3,800 rpm / 344.2 hp @ 5,000 rpm
After gathering the preliminary results, Freiburger decided to find out if muffler choice is an influential factor when it comes to making as much power as possible. To do this, the crew clamped a set of Thrush mufflers into the same exhaust system, replacing the Magnaflow mufflers. As it turns out, the quiter Thrush muffler is indeed more restrictive, sapping more than 10HP from the small block V8. You can see the power ratings below for each muffler setup below: Note, this testing was done on the 3-inch exhaust system.
- Magnaflow mufflers: 399.9 lb-ft @ 3,800 rpm / 344.2 hp @ 5,000 rpm
- Thrush mufflers: 397.2 lb-ft @ 3,800 rpm/ 331.1 hp @4,900 rpm
So, there you have it. As Freiburger points out, those who are on a budget should probably opt for the cheaper 2.5-inch piping, and spend a bit more on a better of mufflers – if you’re looking to make the most power, that is.
Are these findings in alignment with your own experiences? Speak to us in the comment section below.