Invidia 24+ Acura Integra Type-S DE5 R400 Cat-Back Exhaust system - HS23AISFGM3STL

Far more engineering goes into the design of an exhaust system than many realize. From a performance perspective, there is a fine balance between exhaust back pressure and exhaust gas velocity. Too large a diameter pipe, and low down power and torque is sacrificed (particularly on naturally aspirated cars), too small a diameter or added restrictions and bottlenecks in the system, and the engine is unable to push gases out of the combustion chamber efficiently, reducing power and torque. There are many other technical aspects such as 'scavenging effect' which are beyond the scope of this document.

It's not as simple as just strap on a drain pipe and gains for days. A 'quality' exhaust system maximizes performance gains by design.

but the point is

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