Considering an ECU remap for your BMW 5 Series 523i 170hp? A Stage 1 remap can take this E39 - 1995 - 2003 petrol engine from 170 BHP to 187 BHP and from 245 Nm to 272 Nm of torque (naturally aspirated). This engine scores 4.5/10 for remap suitability. Get a free personalised quote from a trusted remap professional and find out exactly what your BMW 5 Series can achieve.
The BMW 5 serie 523i 170hp is a 2.5L naturally aspirated petrol engine producing 170 BHP and 245 Nm from the factory. With a typical Stage 1 remap, output increases to approximately 187 BHP and 272 Nm — a gain of around 17 BHP (10%) and 27 Nm (11%).
This engine has limited remap suitability, with a balanced spread of gains across both power and torque — providing a noticeable improvement across the rev range. The tuning headroom is classified as moderate, based on the percentage gain available from the factory output.
Considerations: Naturally aspirated engine: gains are usually limited; results vary widely.
All figures shown are typical estimates based on aggregated Stage 1 data for this engine variant. Actual results depend on vehicle condition, mileage, and the chosen tuning method. We recommend discussing your specific vehicle with a qualified remap professional.
| Engine | BHP | Gain | Torque | Gain | Score |
|---|---|---|---|---|---|
| 520D 136hp | 136 → 168 | +32 | 280 → 348 | +68 | Good (7.5/10) |
| 525 TDS 143hp |
| 143 → 172 |
| +29 |
| 280 → 350 |
| +70 |
| Good (7.5/10) |
| 520i 150hp | 150 → 165 | +15 | 190 → 208 | +18 | Moderate (4/10) |
| 525D 163hp | 163 → 195 | +32 | 350 → 430 | +80 | Good (7.5/10) |
| 530D 184hp | 184 → 220 | +36 | 390 → 480 | +90 | Good (7.5/10) |
| 525i 192hp | 192 → 208 | +16 | 245 → 270 | +25 | Moderate (4/10) |
| 528i 193hp | 193 → 209 | +16 | 280 → 302 | +22 | Moderate (4/10) |
| 530D 193hp | 193 → 221 | +28 | 410 → 480 | +70 | Good (6.5/10) |
| 530i 231hp | 231 → 246 | +15 | 300 → 325 | +25 | Moderate (4/10) |
| 540i 4.4 V8 286hp | 286 → 300 | +14 | 440 → 460 | +20 | Limited (3/10) |
Get a personalised remap quote for your BMW 5 Series. We'll connect you with a trusted professional in your area.
All figures shown are typical estimates based on aggregated Stage 1 data for this engine variant. Actual results depend on vehicle condition, mileage, and the chosen tuning method.
We recommend discussing your specific vehicle with a qualified remap professional before proceeding.
