Free calculators for planning fuel, engine and drivetrain upgrades. Each calculator shows its formula and lists its sources, and every input is editable.
Fuel system
Fuel pump and injector calculatorInjector size to horsepower on six fuels, checked against a database of pumps from 13 brands.
AN fuel line size calculatorFeed, return and pre-pump line sizes by horsepower and fuel, with a fuel velocity check.
Engine
Turbo boost and airflow calculatorAirflow, boost and compressor pressure ratio for a horsepower target, or power from a known boost.
Compression ratio calculatorStatic compression from bore, stroke, chamber, head gasket and piston, plus gasket-thickness what-ifs.
Accessory pulley speed calculatorAlternator, water pump, A/C and power steering RPM for any crank pulley, with rated-limit checks.