We talk about this subject quite often and continue to learn more about the value of fuel and exhaust flow while testing trucks on our new Taylor Dyno. For instance, our ported and ceramic coated exhaust manifold flows 20% more exhaust, lowers the exhaust temperature by 125 degrees and improves the spool up time of the turbocharger.
What we have recently learned on the C-15 Caterpillar single turbo engines is coupled with our High Performance Cat Turbo the engine gains about 100 horsepower.
We are NOT adding any additional fuel just eliminating restriction and turbulence and the net gain is 3.12 horsepower per pound of turbo boost. That is an incredible gain of power just by changing two items on the engine. Keep in mind these trucks that we test already have our high flow quiet performance mufflers and most of them have the Fleet Air filters already installed. Every day we get back reports from owner-operators that install the manifold and turbocharger at the same time and they tell us they have to learn how to drive their all over again because of the power, rate of acceleration, and response and know we know why they feel such a difference, they have just gained 100 horsepower.
Many of the articles compiled here where written by Bruce Mallinson. Attribution to other contributors is given in the specific articles.