Can exhaust cutouts enhance horsepower?

The Ram 392 Quick Silver features a 470-horsepower, 392 HEMI V-8 engine from the SRT lineup. Enhanced with a cold-air intake kit and headers that incorporate an electronic exhaust cutout, it ensures optimal power and track-ready acoustics. (Courtesy of Chrysler Group LLC)

In the early days of engines, fuel and air were combined in the cylinders, igniting with a

spark. However, residual gases remained, necessitating an exhaust system to expel them. The quicker the exhaust is expelled, the faster the combustion cycle repeats, resulting in increased horsepower. Thus, expelling exhaust swiftly is crucial.

This would be achievable if the complex pathways and mufflers beneath the vehicle could be removed. However, regulations mandate their presence to maintain quiet streets and clean, breathable air.

What if we pledge to bypass the exhaust system solely for safe track racing? In such cases, a Y-shaped exhaust cutout can be installed. Positioned between the engine and muffler, the short pipe, known as "the slant," faces downward and rearward. When additional horsepower is needed, a flange or block plate in the cutout can be manually or electronically adjusted to let exhaust gases bypass the system swiftly. On public roads, the cutout can be closed, directing exhaust through the full system, including the catalyst and muffler.

Indeed, expelling exhaust more rapidly increases horsepower. However, bypassing the muffler results in a louder vehicle, potentially attracting the attention of law enforcement for noise violations.