Air Fuel Ratio Calculator
Calculate air-to-fuel ratio by dividing the measured mass of air by the measured mass of fuel. Enter both measurements in the same mass unit.
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Calculators
Calculators
Planning tools related to motorsport & garage life, with visible assumptions and clearly explained results.
Alternator Output Size Calculator
Estimate the minimum alternator output in amperes needed to supply a vehicle's simultaneous electrical loads, with an adjustable reserve for charging and added demand. This worksheet uses the loads you enter and does not verify an alternator's real-world performance or vehicle compatibility.
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Automotive Voltage Drop Calculator
Estimate the voltage drop across a vehicle circuit from conductor resistance, circuit length, and current. This simplified calculation assumes the entered resistance applies per unit length and that the circuit length includes the complete current path.
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Board Feet Calculator
Calculate the nominal board-foot volume of lumber from its thickness, width, and length, then multiply by the number of matching pieces. Measurements are entered in inches and feet.
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Brake Horsepower Calculator
Estimate engine brake horsepower from measured wheel horsepower and an assumed drivetrain-loss percentage. This simplified model does not replace an engine dynamometer measurement.
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Camshaft Overlap Calculator
Estimate valve overlap in crankshaft degrees from intake duration, exhaust duration, and installed lobe separation angle. This calculation assumes valve events are measured at the same checking height and the cam is installed with its lobe centers symmetric around top dead center.
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Car Fuel Cost Calculator
Estimate the fuel cost of a drive from distance, fuel economy, and fuel price. The estimate assumes the vehicle maintains the entered average fuel economy throughout the trip.
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Car Loan Monthly Payment Calculator
Estimate a fixed monthly principal-and-interest payment from the loan principal, annual interest rate, and term in months. This arithmetic estimate excludes fees, taxes, and other loan costs.
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Car Maintenance Cost Calculator
Estimate a vehicle's annual routine maintenance budget from planned service visits, parts, labor, and an optional contingency allowance. This worksheet uses your own expected prices and does not predict repairs or guarantee future costs.
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Car Restoration Cost Calculator
Estimate a planning total for a car restoration by adding labor, parts, bodywork, and paint costs. Enter your own quotes and expected hours. This worksheet does not predict hidden damage, taxes, or shop-specific charges.
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Compression Height Calculator
Calculate piston compression height from engine deck height, crank stroke, connecting rod length, and desired deck clearance. This geometric estimate assumes the piston is at top dead center and uses consistent units.
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Concrete Volume Calculator
Estimate the volume of concrete needed for a rectangular slab from its length, width, and thickness. The result is the geometric volume before any allowance for waste, uneven ground, or over-excavation.
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Deck Board Quantity Calculator
Estimate the number of deck boards needed by dividing the deck area by the coverage area of one board. Enter both areas in square metres. The result may be fractional, so round up when ordering whole boards and account separately for cuts and waste.
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Differential Ratio Calculator
Calculate the overall drive ratio from ring and pinion tooth counts, then estimate engine RPM at a given vehicle speed using tire diameter and transmission gear ratio. This is a gearing calculation and does not assess whether a setup is safe or suitable for a particular vehicle.
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Drywall Sheet Calculator
Estimate the number of drywall sheets needed from wall and ceiling area, sheet size, and a waste allowance. This area-based estimate excludes openings and does not determine fastening, fire-rating, or structural requirements.
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Engine Bore and Stroke Calculator
Calculate an engine's swept displacement from cylinder bore, stroke, and cylinder count. Enter bore and stroke in the same units to get displacement in cubic inches or cubic centimeters, depending on the unit you enter.
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Engine Compression Ratio Calculator
Calculate an engine's geometric compression ratio per cylinder from swept volume and clearance volume, entered in the same volume unit.
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Engine Displacement Calculator
Estimate total engine displacement from cylinder bore, stroke, and cylinder count. The result is the swept volume of all cylinders, expressed in cubic centimeters.
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Engine RPM Calculator
Estimate engine speed from road speed, tire diameter, transmission gear ratio, and axle ratio. Assumes speed in miles per hour, tire diameter in inches, and no tire slip; the estimate uses 336 as the standard unit-conversion constant.
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Engine Volumetric Efficiency Calculator
Estimate a four-stroke engine's volumetric efficiency from its displacement, engine speed, and measured airflow. Enter displacement in cubic inches, speed in revolutions per minute, and airflow in cubic feet per minute (CFM).
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Fuel Economy Calculator
Estimate a vehicle's fuel economy from the distance traveled and fuel used. Enter the trip distance in miles and fuel consumed in US gallons to calculate miles per gallon (MPG).
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Fuel Pump Flow Calculator
Estimate the minimum fuel pump flow required for an engine using horsepower, brake-specific fuel consumption, and a safety margin. The estimate assumes the selected fuel type's BSFC value and a consistent flow unit.
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Garage Engine Stand Load Calculator
Estimate the fraction of the combined rated capacity of your engine stands represented by an engine's weight. This simple load check assumes the stands share the load evenly and does not replace the stand manufacturer's instructions or a stability assessment.
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Garage Roof Material Area Calculator
Estimate the roof surface area to cover by multiplying garage roof length by width and a waste factor. This simple estimate assumes a rectangular roof plan and does not account for pitch, overlaps, or product-specific coverage.
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Gear Ratio Calculator
Calculate overall drivetrain ratio by multiplying a selected transmission gear ratio by the differential ratio. Enter both ratios as unitless ratios, such as 3.73 for a 3.73:1 differential.
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Gravel Volume Calculator
Estimate the gravel volume needed for a project from its measured length, width, and depth. The result assumes a rectangular area and does not add a compaction or waste allowance.
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Engine Horsepower Calculator
Estimate engine horsepower from torque and engine speed using the standard horsepower relationship. Enter torque in pound-feet and engine speed in revolutions per minute.
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Horsepower to Kilowatts Converter
Convert a vehicle or engine's horsepower rating to kilowatts using the mechanical horsepower conversion factor.
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Injector Size Calculator
Estimate the minimum injector flow per injector from target engine horsepower, brake-specific fuel consumption, injector count, and maximum duty cycle. The estimate assumes evenly distributed fuel demand and requires engine-specific verification.
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Lease Payment Calculator
Estimate a vehicle's monthly lease payment from its negotiated price, down payment, residual value, money factor, and lease term. This estimate excludes taxes, fees, and lender-specific adjustments.
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Linear Feet Calculator
Convert a measured length in feet and inches into linear feet. Enter the measurement for one piece and the number of identical pieces to calculate their combined linear length.
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Nitrous Bottle Refill Cost Calculator
Estimate the total refill cost for one or more nitrous bottles using the number of bottles, fill mass per bottle, and price per kilogram. This simple estimate assumes every bottle receives the same fill mass and uses the same per-kilogram price.
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Oil Change Cost Calculator
Estimate the cost of engine oil and an oil filter from the quantities and prices you enter. This simple estimate excludes labor, taxes, disposal charges, and any other service items.
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Paint Coverage Calculator
Estimate the gallons of paint needed for a project using the area to paint, number of coats, stated coverage per gallon, and an extra allowance for waste.
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Mean Piston Speed Calculator
Calculate mean piston speed in feet per minute from an engine's stroke and crankshaft speed. This arithmetic estimate describes average piston travel and does not assess engine safety or performance limits.
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Power-to-Weight Ratio Calculator
Calculate a vehicle's power-to-weight ratio from its engine output and vehicle weight. Enter power in horsepower and weight in pounds to see horsepower per pound.
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Quarter Mile Time Calculator
Estimate a vehicle's quarter-mile elapsed time from its weight and engine power using a simplified power-to-weight model. The estimate assumes the entered power reaches the wheels and does not account for vehicle setup, track conditions, or driver technique.
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Race Fuel Tank Refill Cost Calculator
Estimate the cost of a race fuel tank refill by multiplying fuel volume by price per liter, then adding container costs. Enter the quantities and prices you want to include.
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Rear Axle Ratio Calculator
Estimate rear axle ratio from engine speed, tire diameter, and transmission gear ratio. The result is a theoretical ratio based on a direct relationship between these inputs and assumes no torque-converter slip or tire growth.
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Square Footage Calculator
Calculate the floor or surface area of a rectangular space from its length and width. Enter both measurements in feet to get area in square feet.
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Stair Tread Material Calculator
Calculate the total top-surface area of stair treads from their count, width, and depth. The result is a planning estimate in square metres and excludes risers, nosings, waste, and other installation materials.
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Stoich Calculator
Calculate lambda from an AFR reading and the stoichiometric AFR value you provide. This arithmetic conversion does not determine a safe engine or nitrous tune.
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Tile Calculator
Estimate the tile coverage area for a rectangular room, including an allowance for cuts and breakage.
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Tire Pressure Difference Calculator
Compare a tire's current pressure with its specified target pressure to calculate the difference in PSI. This arithmetic comparison does not determine the correct pressure for a vehicle or tire.
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Tire Size Calculator
Compare tire dimensions and estimate overall diameter, sidewall height, circumference, and revolutions per mile from the tire width, aspect ratio, and wheel diameter.
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Torque to Horsepower Calculator
Estimate engine horsepower from torque and engine speed using the standard relationship between torque, RPM, and horsepower. Enter torque in pound-feet and engine speed in revolutions per minute.
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Vehicle Depreciation Calculator
Estimate a vehicle’s value after a chosen ownership period using a straight-line depreciation assumption. Enter the purchase price, estimated resale value, and years owned to calculate the estimated value lost and annual average depreciation.
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Wallpaper Roll Calculator
Estimate the number of wallpaper rolls needed from wall dimensions, roll coverage, and an allowance for pattern matching and cutting waste. This estimate assumes rectangular walls and does not subtract doors or windows.
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Wheel Offset Calculator
Estimate how a wheel's inner and outer positions change when its width or offset differs from a reference wheel. This geometric comparison does not determine vehicle fitment or clearance.
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Wheel Spacer Stack Thickness Calculator
Calculate the combined thickness of a wheel spacer stack by multiplying the number of spacers by the thickness of each spacer. Enter measurements in millimeters. This arithmetic estimate assumes every spacer has the same thickness and does not assess fitment or vehicle safety.
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