Sea-Doo 300 hp vs. 325 hp – Differences, ECU & Tuning Options
In the Sea-Doo lineup, two performance levels are particularly common: 300 hp and 325 hp. Both variants use the same supercharged Rotax 1630 ACE engine – yet the differences are significant, especially when it comes to the ECU, tuning, and products from M-JET FLASHER.
Same Engine – Different Technology
| Sea-Doo 300 hp | Sea-Doo 325 hp | |
|---|---|---|
| Engine | Rotax 1630 ACE | Rotax 1630 ACE |
| Displacement | 1630 ccm | 1630 ccm |
| Charging | Supercharger | Supercharger |
| ECU | Bosch ME17.8.5 | Bosch MG1CA920 |
| GPS/Vmax Limiter | No | Yes (factory) |
| Tuning without Unlock | Yes | No |
| ECU Unlock needed for Tuning | No | Yes |
| Models | RXP-X 300, RXT-X 300, GTX 300 (up to 2023) | RXP-X 325, RXT-X 325, GTX Limited 325 (from 2024) |
The 300 Series: Bosch ME17.8.5 – Ready for Tuning
The 300 hp models run on the Bosch ME17.8.5 ECU – maximum flexibility without prerequisites:
- M-JET FLASHER for RXP-X / RXT-X 300 – tune directly, no unlock
- M-JET FLASHER for GTX 300 – ready for immediate use
- M-JET FLASHER for GTX 230/300 (2018–2024) – fully supported
- M-JET DIAGNOSTIC – fault codes, live data including boost pressure, service functions
- No factory GPS speed limiter
The 325 Series: Bosch MG1CA920 – More Power, New Possibilities
The 325 hp models feature the more modern Bosch MG1CA920 ECU. The following functions work immediately – without an unlock:
- M-JET DIAGNOSTIC – diagnostics, fault codes, live data – Plug & Play
- M-JET Vmax Remover – remove GPS/Vmax limiter on RXP-X 325, RXT-X 325, and GTX Limited 325 – no performance change, activate via app
For true performance tuning on the 325 series: first perform the one-time ECU Unlock for Sea-Doo 325 – then all tuning stages with the M-JET FLASHER.
All Sea-Doo Models and Their Tuning Options
| Model | ECU | Tuning |
|---|---|---|
| Sea-Doo Spark & Spark Trixx (2014–2026) | ME17.8.5 | M-JET FLASHER – direct |
| Sea-Doo GTI (2014–2021) | ME17.8.5 | M-JET FLASHER – direct |
| Sea-Doo GTX 130 / 170 | ME17.8.5 | M-JET FLASHER – direct |
| Sea-Doo Wake 170 | ME17.8.5 | M-JET FLASHER – direct |
| Sea-Doo Wake Pro 230 | ME17.8.5 | M-JET FLASHER – direct |
| Sea-Doo GTX 230 / 300 (2018–2024) | ME17.8.5 | M-JET FLASHER – direct |
| Sea-Doo RXP-X / RXT-X 300 (2016–2023) | ME17.8.5 | M-JET FLASHER – direct |
| Sea-Doo GTX 300 (2016–2023) | ME17.8.5 | M-JET FLASHER – direct |
| Sea-Doo RXP-X / RXT-X / GTX Limited 325 | MG1CA920 | ECU-Unlock → M-JET FLASHER |
Which Path Is Right for You?
300 series, easy tuning? Go directly to the M-JET FLASHER – no prerequisites needed.
325 series, just remove Vmax limiter? M-JET Vmax Remover – Plug & Play, no unlock, reversible.
325 series, true performance tuning? First perform ECU Unlock – then all stages with the M-JET FLASHER.
Keeping an eye on engine health? M-JET DIAGNOSTIC – works on 300 and 325 series without unlock.
Extras for All Sea-Doo Models
M-JET Temperature Module – oil or water temperature directly on the display, from MY 2018, Plug & Play
M-JET Auto-Sport Module – automatically in Sport mode after every start
M-JET CTEK Charging Adapter – maintenance charging of the battery via the original tow pylon port
