Cartridge HX35W 3598897 4033206 Cummins 6BTAA

Will Engine modifications and big bore exhausts improve my vehicles performance?

Many modifications to the engine will increase the performance of the vehicle above the factory specifications. These modifications will introduce greater stress on the turbocharger and may cause premature failure.

One of the most common modifications made too many vehicles is the exhaust system. A larger exhaust system (Big-Bore) is one of the cheapest and easiest methods of increasing an engine's horsepower. This reduces the exhaust gas back-pressure and allows an increase of gas flow across the turbocharger. The problem is the original turbocharger was designed to work on that engine with a known gas flow and backpressure. If the gas flow is increased the wastegate valve cannot spill enough of the gas flow and the speed of the turbine rotor shaft increases, resulting in an over-speed / over-boost situation. An overspeed will result in premature turbocharger failure. This will often be seen in the form of thrust bearing failure (overloading); Compressor wheel failure (over-speeding); Shaft breakages (pulse shock waves).
Other modifications such as computer chip enhancements can cause over-fueling, which may result in fuel still burning when the exhaust valve opens. This causes excessive thermal loading on the turbocharger. After market boost controllers and actuator bleed off valves by their very nature can allow over boosting (overspeeding), which will cause premature turbocharger failure.