Technical Tools
Helpful calculators and tools for your Mustang projects.
T5 Speedometer Gear Calculator
Determine the correct speedometer gear for your T5 swap based on axle ratio and tire size.
Gear Ratio Calculator
Speed at any RPM in every gear for T5, T56 and custom transmissions, plus a drive simulator that revs through the gears.
Carburetor CFM Calculator
The carburetor CFM any engine needs, with the nearest common four-barrel sizes and every Autolite 1100, 2100 and 4100 on one rating basis.
Tire Size Calculator
Compare two tire sizes: diameter, sidewall, revolutions per mile, speedometer error and ride height, with a to-scale drawing of both tires.
Mustang VIN Decoder
Model year, assembly plant, body style and engine from a 1964½–1973 Mustang VIN, with every year’s codes.
Mustang Door Tag Decoder
Body, paint, trim, build date, sales district, axle and transmission codes from a 1964½–1973 Mustang door tag (data plate).