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Stage 3 ECU

This is an advanced, yes still easy to use, ECU for modular engines. This ECU has numerous features, including variable idle and rpm limit sensitivity, AFR Correction for supercharged engines, and a precise Variable Speed Stoichiometry system, dubbed "VSS", that changes engine stoichiometry based on engine speed.

Quick run-down of the ECU properties:

"RPS Limit": the maximum RPS the ECU will alow the engine to operate at. Please note modular engins will not run higher than 60 RPS.

"RPS Limit Roughness": How sensitive the RPS Limiter is, values too high will cause the engine to 'bounce' off the limiter, and values too low will cause a loss of torque at high engine speeds. (I suggest 1 for engines with flywheels and 0.1 for engines without, however more powerful engines may need lower values)

"Idle RPS": The speed the engine will idle at. Please note that engines will stall stall around 2.1 RPS.

"Idle Roughness": Similar to "RPS Limit Roughness", this controls how sensitive the idle system is. Values too high may cause rough idle, and values too low make the engine easier to stall. This value also can be lower with more powerful engines.

"AFR Adjustment": Controls the function that converts target AFR to the value needed to make the engine run at that value. 6.875 should be used for naturally-aspirated engines and should not be any lower, but the value may be raised in the case of supercharged engines. This value is clamped between 6.875 and 100. (while this system is complicated, it keeps the AFR value from oscillating, making the engine run better when properly tuned)

"Non-VSS Stoich": The target Stoichiometric the engine will run at when VSS is disengaged. (i recommend 0.2 as it's the most efficient)

"VSS Stoich": The target Stoichiometric the engine will run at when VSS is engaged. (I recommend 0.4 as it is the most powerful)

"VSS Engagent RPM": The RPM at which VSS switches from the "Non-VSS" value to the "VSS" value. (I recommend 2900 as this is where torque normally starts to drop off, engaging at this speed can keep torque from dropping)


Now that I've properly complicated your brain, I hope you enjoy! I have some recommended values down below.

"RPS Limit Roughness": ~0.1 for engines with no flywheel, ~1 for engines with flywheels

"Idle RPS": ~5-10, set at the higher end of the spectrum if you're worried about stalling

"Idle Roughness": ~1 for engines with no flywheel, ~5 for engines with flywheels

"AFR Adjustment": 6.875 for engines with no supercharger, ~10 for engines boosted to 50 pressure

"Non-VSS Stoich": 0.2

"VSS Stoich": 0.4

"VSS Engagement RPM": 2900