Welcome to the Motorift Engine Simulation
This is the simple version, try the full app here
It uses engine airflow (cid and rpm), an engine tune (air:fuel, bsfc, and boost or vacuum) and weather to estimate horsepower from the amount of air moving through the engine.
The parts calculations are estimates and "minimum" sizes. This is just a collection of calculators. The best way to use it is to find your stock calulations (bsfc, boost) and then add modifications or weather changes
Weight and drivetrain loss are used in the 1/4 mile estimate
Engine Size and Speed
These are minimum size to support the horsepower and of course these are estimates and nothing is written in stone what will or will not work
Header primary size is for peak torque at the RPM you selected
Download the app or use the browser app (login to motorift.com) for a more advanced version of the engine simulation.