#tuning

Turbocharger and boost engineering maths as an API, computed locally and deterministically — the pressure-ratio, charge-air and airflow numbers a tuner, engine builder or motorsport engineer sizes forced induction with. The pressure-ratio endpoint gives the compressor pressure ratio = absolute manifold pressure ÷ ambient = (atmospheric + boost) ÷ atmospheric, so 10 psi at sea level is a 1.68 ratio — the x-axis of every compressor map, which climbs at altitude where ambient pressure is lower. The charge-air endpoint shows why an intercooler matters: compressing air heats it (T₂ = T₁ × (1 + (PR^0.2857 − 1)/efficiency)), and hot air is less dense, so the real gain is the charge density ratio = pressure ratio × (T₁/T_charge), not the pressure ratio alone — 10 psi at 70 % compressor efficiency makes ~93 °C and a 1.37 density ratio with no intercooler, rising toward 1.6 once an intercooler claws back the heat, and the estimated power gain tracks the density. The airflow endpoint gives the engine mass airflow ≈ displacement × (rpm/2) × volumetric efficiency × charge density, in lb/min — the y-axis of the compressor map you plot against the pressure ratio to land in the efficient island and avoid surge or choke. Everything is computed locally and deterministically, so it is instant and private. Ideal for engine-tuning and turbo-sizing tools, dyno and data-logging apps, and motorsport calculators. Pure local computation — no key, no third-party service, instant. Sizing estimates — verify on a dyno. 3 compute endpoints. For engine displacement and compression use an engine API; for shop compressed air a compressor API.

api.oanor.com/turbo-api

Air-fuel ratio and lambda maths for engine tuning as an API, computed locally and deterministically — the lambda, AFR and mixture numbers a tuner, ECU developer or motorsport engineer dials fuelling in with. The lambda endpoint turns a measured air-fuel ratio into lambda (the AFR divided by the fuel's stoichiometric AFR — 14.7 for gasoline) and the equivalence ratio φ = 1/lambda, classifying the mix as rich, stoichiometric or lean: a gasoline AFR of 13.0 is lambda 0.88, an 11.6 % rich mixture, the sort used at wide-open throttle for power and a cooler, safer burn. The afr endpoint runs it the other way — pick a target lambda and it gives the AFR the wideband should read — and because the AFR number is fuel-specific (E85's stoichiometric AFR is about 9.8, not 14.7) it always works from the right fuel, which is why pros tune in lambda when switching fuels. The mixture endpoint links the air the engine breathes to the fuel the injectors must add: give an air mass and a target lambda and it returns the fuel mass (or vice-versa), the heart of how an ECU sizes fuelling from measured airflow. Built-in stoichiometric ratios for gasoline, E10, E85, ethanol, methanol, diesel, LPG, propane, methane/CNG and hydrogen, or pass your own. Everything is computed locally and deterministically, so it is instant and private. Ideal for engine-tuning and dyno tools, ECU and standalone-management apps, motorsport and data-logging utilities. Pure local computation — no key, no third-party service, instant. 3 compute endpoints. For engine displacement and power use an engine API; for chemical reaction stoichiometry a stoichiometry API.

api.oanor.com/airfuel-api

Vehicle-suspension maths as an API, computed locally and deterministically — the spring and frequency numbers a racer, tuner or chassis engineer sets a car up with. The wheel-rate endpoint converts a spring rate to the rate the wheel actually feels: wheel rate = spring rate × motion ratio², where the motion ratio is the spring's travel per unit of wheel travel — a 200 lb/in spring at a 0.7 motion ratio gives a 98 lb/in wheel rate, because the spring's leverage softens it. The frequency endpoint gives the ride (natural) frequency at a corner, f = (1/2π)·√(wheel rate × g ÷ corner sprung weight), the number that really sets the ride: luxury cars run about 0.5–1.2 Hz, sporty street 1.2–1.7, race cars 2 Hz and up. The spring-rate endpoint inverts it — the spring rate needed to hit a target frequency for a corner weight and motion ratio — so you can pick the frequency for the car's job and get the spring straight out. Everything is computed locally and deterministically, so it is instant and private. Ideal for motorsport and tuning apps, chassis-setup and corner-balancing tools, suspension-design calculators, and engineering study aids. Pure local computation — no key, no third-party service, instant. Live, nothing stored. 3 compute endpoints. Estimates — real ride also depends on damping and tyres.

api.oanor.com/suspension-api

PID-controller-tuning maths as an API, computed locally and deterministically. The ziegler-nichols endpoint computes controller gains with the closed-loop (ultimate-gain) method: from the ultimate gain Ku at which the loop sustains oscillation and its period Tu it returns the proportional, integral and derivative gains for a P, PI, PD or PID controller using the classic table (PID: Kp = 0.6·Ku, Ti = 0.5·Tu, Td = 0.125·Tu), in both the standard (Ti, Td) and parallel (Ki, Kd) parameters. The reaction-curve endpoint computes gains with the open-loop method from a step-response process model — the process gain K, the dead time L and the time constant T — using the Ziegler-Nichols reaction-curve table (PID: Kp = 1.2·T/(K·L), Ti = 2L, Td = 0.5L). The convert endpoint translates between the parallel form (Kp, Ki, Kd) and the standard form (Kp, Ti, Td) using Ki = Kp/Ti and Kd = Kp·Td. Everything is computed locally and deterministically, so it is instant and private. Ideal for industrial-automation, robotics, process-control, motor-control and IoT app developers, controller-tuning and loop-design tools, and control-systems education. Pure local computation — no key, no third-party service, instant. Live, nothing stored. 3 endpoints. This is PID controller tuning; for op-amp circuits use an op-amp API and for resonance and reactance a resonance API.

api.oanor.com/pid-api