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Aftermarket ECUs
Generally if you're going this route you probably don't need any guidance about how to do it. Here are a few aftermarket ECU options and some differences:
| Stock PCM | MegaSquirt | Haltech Sport | Haltech Elite 750 | Haltech Elite 2500 | Holley Terminator X | Holley HP EFI | Holley Dominator | |
|---|---|---|---|---|---|---|---|---|
| Cost of ECM | ~$100 - $300 for tuning tools | ~$600 | $1,187 | $1,200 for ecu alone | $1,950 for ecu alone | $1,200 with harness and 3.5“ lcd | $1,433 | $2,300 |
| Cost of Wiring Harnesses | Uses factory 3800 harness | extra $224 for premium harness | extra $255 for premium harness | Comes with the harness | ~$700 Can buy as a kit | >$700 Harnesses sold individually |
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| Ease of harness install for 3800 | Plug and Play | Requires custom harness | Plug and Play | Requires custom harness | Requires custom harness | Will need some modification or custom harness | Requires custom harness | Requires custom harness |
| Ease of use | Moderate | Difficult | Easy | Easy | Easy | Easy | Easy | Easy |
| Reviews | Good enough for most people | Difficult to put together, but a lot expandability. Pretty dated now | not great | State of the art. Created in Australia though support can be tricky | Terminator X is a lot like HP EFI but with a few less bells and whistles | Similar to Dominator but with less inputs/outputs | Dominator is basically the state of the art. Holley is very reputable | |
| water-proof? | yes | no | no | yes | yes | no | yes | yes |
| Wideband auto-tuning support | no | no | no? | yes | yes | yes | yes | yes |
| MAP limits for speed density tuning | 1.4 bar | 22 psi for ECM's internal MAP sensor | 5 bar | 5 bar | 7 bar | |||
| drive by wire support | Some PCMs | yes | yes | yes | yes x2 | |||
| Transmission control | yes | yes | yes | yes | only with “Terminator X Max” | no | yes | |
| anti-lag / launch control built in | no | yes | no | yes | yes | yes | yes | |
| CO2 control | no | no | no | yes | yes | yes | yes | |
| Boost by Gear | no | yes | yes | yes | yes | yes | ||
| Flex Fuel sensor support | not with a 3800 PCM | yes | yes | yes | yes | yes | yes | |
| Stages of nitrous control | 0 | 1 | 1 | 6 | 4 | 8 | ||
| fuel injection outputs | 6 | 6 | 1-6 | 1-8 | up to 8 | up to 8 | 12 “peak” + 12 “hold” = 24 injectors | |
| Ignition Outputs | OEM | 6 | 8 | 4 ground Can expand with CAN IO Module | 4 12v or ground PWM Can expand with CAN IO Module | 20 12v PWM 16 ground PWM Can expand with CAN IO Module |
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| Digital Outputs | none | 28 | 0 | |||||
| Analog inputs | none | 10 | 20 | 4 | 4 | 13 “multi-inputs” + 30 sensor inputs (0-5v) | ||
| injector stages for fueling | 0 | 4 | ||||||
| Internal Data Logging | no | yes | yes | no | yes | yes | ||
| Known Oddities | oh boy, yes | not potted can't use external battery charger with ECU connected | can't use external battery charger with ECU connected | can't use external battery charger with ECU connected |