A simulated engine on a dyno, run by a standalone ECU you tune yourself. Change the fuel map, the timing or the boost and watch what happens to the power curve, the mixture and the knock sensor.

It behaves like the real thing. The engine model runs every combustion event. Lean it out and it misfires. Add too much timing and it knocks, then cracks a piston. Fit bigger injectors without telling the ECU and it floods.

THE ECU
- Fuel VE, lambda targets, ignition, boost target and wastegate duty, idle, warmup, cranking, accel enrichment and dead times
- Closed loop, knock control, rev and boost limiters, auto learn and "Fix from pull"
- Select cells, drag curves, type values, interpolate and smooth, in a grid or in 3D
- Lay the data log over any table and see which cells ran lean or knocked

THE ENGINES
- Ten engines: fours, a flat four, straight sixes, V6s and V8s
- Naturally aspirated, turbo, twin turbo, supercharged and nitrous
- Nearly 100 parts: injectors, pumps, lines, regulators, turbos, housings, wastegates, blowers, cams, pistons, rods, head gaskets and fuels, E85 included

THE DYNO
- Hold any rpm at any throttle, or do a full wide open throttle pull
- Power, torque, mixture, boost and timing on every run
- A full data log you can zoom into
- Engine health: knock, over-revving, boost and heat all wear parts out, and some failures are sudden

CAREER MODE
Start with a rented unit, a small dyno, a stock project car and $1,500. Customers bring in cars with vacuum leaks, tired fuel pumps, stuck wastegates, burnt valves and lying sensors, or ask for a power target on a budget. Find the fault, fix it, tune it and hand it back for a test drive that grades your work.
- Ten kinds of job, from base tunes to E85 conversions, race class builds and blown engine rescues
- Eight regulars who bring the same car back chapter after chapter, with your parts and tune still on it
- Diagnostic tools, a bigger dyno, more bays, weather, deadlines and rent
- Dyno Day every Saturday against rival shops, and 23 achievements

LEARN
A guided tutorial takes a broken project car from flooding on the stand to a full tune. Twelve more lessons cover VE tuning, MBT, knock, boost control, injector swaps, fuel system limits, E85, nitrous, big cam idle and cold starts.

FREE AND PRO
The Turbo Four and the guided tutorial are free, with every part and every table. Tuning Simulator Pro is a one-time purchase that unlocks all ten engines, custom builds, every lesson and Career mode. No subscription, no ads, no account.