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Core short-block math used when planning, blueprinting or assembling an engine: displacement, compression, rotating-assembly…
Valvetrain and airflow math for head porting, cam selection and degreeing. These tools turn flow-bench numbers and cam cards into…
Conversions and corrections used every time an engine is measured or a power claim is compared: torque-to-power, drivetrain loss…
Track math for the quarter and eighth mile: ET and MPH prediction, horsepower back-calculated from timeslips, weather corrections…
Sizing and tuning math for the induction and fuel system: carburetor and injector sizing, lambda targets, boost pressure ratios…
Everything that connects engine rpm to road speed: axle ratios, tire diameters, speedometer error, cruise rpm after a gear or…
Chassis setup and load math: spring and wheel rates, motion ratios, corner weights, weight transfer, wheel fitment, and the…
Stopping, cornering and airflow math: brake balance and hydraulics, stopping distance, rotor heat load, grip-limited cornering…
Consumer-side running-cost math: real-world MPG, trip fuel cost, EV efficiency, charging time and cost, depreciation and total…
Most used in automotive, diesel & motorsports
- Engine Displacement CalculatorSwept-volume definition (SAE J1349 engine displacement)Engine displacement is the total volume every piston sweeps in one full revolution of the crank, and it follows directly from…
- Engine Compression Ratio CalculatorSAE static compression ratio definitionStatic compression ratio is the single number that decides which fuel your engine can live on, and it is set entirely by…
- Volumetric Efficiency CalculatorIdeal-gas volumetric efficiency (Heywood)Volumetric efficiency tells you how completely each cylinder fills compared with its own swept volume. Enter your displacement…
- Horsepower from Torque CalculatorMechanical power definition, 1 hp = 33,000 ft·lbf/minPower is torque multiplied by rotational speed, and the constant 5,252 is the only thing standing between the two. Enter torque…
- Power to Weight Ratio CalculatorRace-weight convention (weight as raced, driver included)Power to weight ratio is the single number that predicts how hard a vehicle accelerates, and it is the number racing classes…
- Quarter Mile ET & MPH CalculatorFox and Huntington ET correlationsEnter race weight with the driver in the seat and flywheel horsepower, and this calculator predicts the elapsed time and trap…
- Trap Speed Horsepower CalculatorTrap-speed cube law (empirical constant)Terminal speed at the end of a drag strip is set almost entirely by power and weight, which makes it the cheapest honest…
- Carburetor CFM CalculatorFour-barrel CFM rated at 1.5 inHg, two-barrel at 3.0 inHgA carburettor has to flow the air the engine can actually swallow at peak power — no more, or velocity and signal…
- Fuel Injector Size CalculatorBrake specific fuel consumption methodInjector sizing is a fuel-mass problem, not a horsepower problem: the engine needs a certain mass of fuel per hour to make the…
- Turbo Pressure Ratio CalculatorU.S. Standard Atmosphere 1976 for ambient pressurePressure ratio is the vertical axis of every compressor map, and it is not the same thing as boost. It is absolute pressure at…
- Boost Horsepower Gain CalculatorIdeal-gas charge density method, k = 1.4Boost makes power by raising the density of the air in the cylinder, and density depends on pressure and temperature &mdash…
- Axle Gear Ratio & Final Drive CalculatorRing-and-pinion ratio identityEnter the tooth counts stamped on your ring gear and pinion and this calculator returns the axle ratio, the overall drive ratio…