With all the different MegaSquirt options out there, choosing the right system can be a bit intimidating. The first decision you’ll need to make is the overall approach. Do you want to keep expenses as low as possible by soldering your own kit together? Or would you rather spend a bit more to save a bit of time? Here’s a comparison of the different approaches you can take.
| MS1 V2.2 | MS1 V3.0 / V3.57 | MS2 V3.0 / V3.57 | MS3-Pro | MicroSquirt | MicroSquirt Module | DIYPNP | MSPNP | |
| Kit prices* | $140 | $187 | $247 | N/A | N/A | N/A | $460 | N/A |
| Assembled prices* | $240 | $335 | $405 | $1,099-$1,349 | $315 | $250 | N/A | $799-$1599 |
| Summary | Basic do it yourself system, intended mainly for fuel-only installs but can be modified for limited ignition controls | Basic do it yourself system, adds more ignition control options than V2.2 | More sophisticated do it yourself system with faster processor | Flagship stand alone; Full featured; fastest processor; Generous I/O | Small preassmebled unit with batch fire fueling and multiple spark outputs | Ready made circuit board for installing in custom circuit boards or slipping into OEM ECU case | MicroSquirt Module based plug in system | Complete plug in system – current ones are MS2 & MS3-Pro based |
| Connector type | D-Sub | D-Sub | D-Sub | AMPSeal | AMPSeal | Header pins | OEM | OEM |
| Hardware | MS1 V2.2 | MS1 V3.0 / V3.57 | MS2 V3.0 / V3.57 | MS3-Pro | MicroSquirt | MicroSquirt Module | DIYPNP | MSPNP |
| Injector channels | 2, batch fire | 2, batch fire | 2, batch fire | For complete feature set, please visit MS3Pro.com | 2, batch fire | 2, batch fire (can be expanded to 4 with modifications) | 2, batch fire (can be expanded to 4 with modifications) | 2, batch fire |
| Max low impedance injectors ** | 4 (16 with optional flyback board) | 16 | 16 | 2 | 2 | 2 | Not recommended | |
| Max high impedance injectors | 12 | 16 | 16 | 8 | 8 | 8 | Depends on factory wiring | |
| Standard ignition outputs | None | None | 1 logic level | 2 logic level | 2 logic level | 4 high current or logic level | As many as needed for factory wiring | |
| Optional ignition outputs | Up to 6 | Up to 6 | Up to 6 | Up to 4 | Up to 4 | |||
| Idle control | On/off | On/off, PWM (V3.57) | On/off, PWM (V3.57), Stepper | On/off, PWM | On/off, PWM | On/off, PWM | PWM | |
| MAP sensor | 2.5 bar internal, upgradeable to 4 bar | 2.5 bar internal, upgradeable to 4 bar | 2.5 bar internal, upgradeable to 4 bar | External | External | 2.5 bar internal, upgradeable to 4 bar | Internal, depends on model | |
| Ignition input types | Hall, optical, points | VR (magnetic pickup), Hall, optical, points | VR (magnetic pickup), Hall, optical, points | VR (magnetic pickup), Hall, optical, points | VR (magnetic pickup), Hall, optical, points | VR (magnetic pickup), Hall, optical, points | Designed to work with stock sensors | |
| Second VR input channel | No | No | No | Yes | Yes | Yes | Depends on application | |
| O2 sensor input | Single narrow band or wideband with external controller | Single narrow band or wideband with external controller | Single narrow band or wideband with external controller | 2X narrow band or wideband with external controller | 2X narrow band or wideband with external controller | 2X narrow band or wideband with external controller | Single narrow band or wideband with external controller | |
| Other sensors | CLT, IAT, TPS, battery voltage | CLT, IAT, TPS, battery voltage | CLT, IAT, TPS, battery voltage | CLT, IAT, TPS, battery voltage, flex fuel, extra analog input | CLT, IAT, TPS, battery voltage, flex fuel, extra analog input | CLT, IAT, TPS, battery voltage, flex fuel, extra analog input | CLT, IAT, TPS if applicable, battery voltage | |
| Fuel pump output | Standard | Standard | Standard | Standard | Standard | Standard | Standard | |
| Boost control | Optional | Optional | Optional | Can use IAC output | External hardware needed | Standard | Standard | |
| General purpose outputs | Optional – up to 4 | Optional – up to 4 | Optional – number depends on configuration | Standard – 2 | Standard – 2 | Standard – 4 | As needed | |
| Tach output | Optional | Optional | Optional | Standard | Standard | Standard | As needed | |
| Nitrous | Optional, single stage | Optional, single stage | Optional, 2 stage | NA | External hardware needed | Minor mods needed | NA | |
| Tuning input | RS232 serial | RS232 serial | RS232 serial | RS232 serial | RS232 serial | RS232 serial | RS232 serial | |
| CAN communications | No | No | Yes | Yes | Yes | Yes | No | |
| Firmware features | MS1 V2.2 | MS1 V3.0 / V3.57 | MS2 V3.0 / V3.57 | MS3-Pro | MicroSquirt | MicroSquirt Module | DIYPNP | MSPNP |
| Max fuel table size | 12 x 12 | 12 x 12 | 16 x 16 | For complete feature set, please visit MS3Pro.com | 16 x 16 | 16 x 16 | 16 x 16 | 12 x 12 |
| VE table resolution | 1% | 1% | 1% | 1% | 1% | 1% | 1% | |
| RPM resolution | 100 rpm | 100 rpm | 1 rpm | 1 rpm | 1 rpm | 1 rpm | 100 rpm | |
| Acceleration enrichment | TPS, MAPDot, RPM based | TPS, MAPDot, RPM based | TPS, MAPDot, model based | TPS, MAPDot, model based | TPS, MAPDot, model based | TPS, MAPDot, model based | TPS, MAPDot, RPM based | |
| Fuel load | Speed density, alpha-N, optional MAF input | Speed density, alpha-N, optional MAF input | Speed density, alpha-N, MAP/Baro | Speed density, alpha-N, MAF, MAP/Baro | Speed density, alpha-N, MAF, MAP/Baro | Speed density, alpha-N, MAF, MAP/Baro | Speed density, alpha-N | |
| Battery voltage correction | Yes | Yes | Yes | Yes | Yes | Yes | Yes | |
| Spark table size | 12 x 12 | 12 x 12 | 12 x 12 | 12 x 12 | 12 x 12 | 12 x 12 | 12 x 12 | |
| Max spark resolution | 0.3 degrees | 0.3 degrees | 0.1 degrees | 0.1 degrees | 0.1 degrees | 0.1 degrees | 0.1 degrees | |
| Injector timing | Not adjustable | Not adjustable | Timed within crank pulses | Timed within crank pulses | Timed within crank pulses | Timed within crank pulses | Not adjustable | |
| Basic distributor based ignition control | Yes (not recommended for magnetic pickups) | Yes | Yes | Yes | Yes | Yes | N/A | |
| EDIS | Yes | Yes | Yes | Yes | Yes | Yes | N/A | |
| Basic missing tooth wheels | Yes | Yes | Yes | Yes | Yes | Yes | N/A | |
| Rotary trailing spark | Not recommended | Yes | Yes | Not enough outputs | Yes | Yes | N/A | |
| Odd fire capabilities | Fuel only | Fuel only | Yes | Yes | Yes | Yes | N/A | |
| Exotic trigger wheels | Miata / 4G63, Neon | Miata / 4G63, Neon | Miata / 4G63, Neon, Subaru, many others | Miata / 4G63, Neon, Subaru, many others | Miata / 4G63, Neon, Subaru, many others | Miata / 4G63, Neon, Subaru, many others | Miata | |
| Barometric correction | Start-up, optional real time | Start-up, optional real time | Start-up, optional real time | Start-up, optional real time | Start-up, optional real time | Start-up, optional real time | Depends on application | |
| Rev limiter types | Timing retard, spark cut, fuel cut | Timing retard, spark cut, fuel cut | Timing retard, spark cut, fuel cut | Timing retard, spark cut, fuel cut | Timing retard, spark cut, fuel cut | Timing retard, spark cut, fuel cut | Timing retard, spark cut, fuel cut | |
| 2 step rev limiting | Optional | Optional | Optional | N/A | Optional | Optional | Standard | |
| Data logging | External | External | External | External | External | External | External | |
| * Base price includes standard bill of materials – additional components / mods can increase the price.** Injector resistors can be used to drive larger numbers of low impedance injectors. | ||||||||
