The S55 in the F8x M3 and M4 cools charge air with a top mounted water to air intercooler fed by two parallel radiators, and the OE unit uses a tube and fin core with clamped plastic end tanks that can crack and leak coolant or boost. This do88 BigPack replaces the intercooler, both plastic charge pipe kits and both charge air circuit radiators in one package. The intercooler is a bar and plate unit with 3D freeform end tanks TIG welded to the core and 85 percent more core volume than stock, and do88 measured 16 to 17 percent higher air flow and intake air temperatures 9 to 14°C lower depending on configuration. On a BootMod3 Stage 1 car do88 recorded a 13 hp peak gain, up to 25 hp through the midrange and up to 52 Nm more torque. The radiators add cooling face area, core thickness and multichannel tube cores to pull the charge air circuit water temperature down.
Specifications
| Type | Water to air top mount intercooler, charge pipe and charge air radiator package (do88 BigPack) |
| Material | Bar and plate core with 3D freeform end tanks TIG welded to the core |
| Core Volume | 85% larger than the OE top mount intercooler |
| Air Flow | 16 to 17% higher than OE |
| Intake Air Temperature | 9 to 14°C lower than OE depending on configuration |
| Power Gain | 13 hp peak, up to 25 hp midrange and up to 52 Nm, measured on a BootMod3 Stage 1 car |
| Configuration | Intercooler plus both charge pipe kits plus both charge air circuit radiators |
| Included | Top mount intercooler, turbo to intercooler pipes, intercooler to throttle body J-pipe, front mounted large radiator, side mounted small radiator |
| Fitment Notes | The radiator equipped BigPack does not fit the BMW M2 Competition F87 |
| Quantity | 1 (complete kit) |
| OEM Replacement | 17517846235, 11617846245, 11617846246, 11617848447, 11618057992 |
| Part Number | BIG-250-WC-SS |
This part fits:
| Year | Make | Model | Submodel |
|---|---|---|---|
| 2015 | BMW | M3 | Base, Competition (F80) |
| 2016 | BMW | M3 | Base, Competition (F80) |
| 2017 | BMW | M3 | Base, Competition (F80) |
| 2018 | BMW | M3 | Base, Competition (F80) |
| 2015 | BMW | M4 | Base, Competition, GTS, CS (F82/F83) |
| 2016 | BMW | M4 | Base, Competition, GTS, CS (F82/F83) |
| 2017 | BMW | M4 | Base, Competition, GTS, CS (F82/F83) |
| 2018 | BMW | M4 | Base, Competition, GTS, CS (F82/F83) |
| 2019 | BMW | M4 | Base, Competition, GTS, CS (F82/F83) |
| 2020 | BMW | M4 | Base, Competition, GTS, CS (F82/F83) |
Shipping
- In-stock orders placed before 3 PM EST ship the same day — everything else ships within 24 hours.
- Standard, expedited, and overnight options at checkout.
- Oversized items ship by freight and take longer.
- Backordered items ship as soon as stock lands — contact us for lead times.
- International orders: prices do not include VAT, duties, or import fees. Your country charges these at import and they are the buyer’s responsibility.
Returns
- 30-day returns on new, uninstalled items in original packaging with all hardware.
- Standard returns: 8% restocking fee, buyer pays return shipping. Both waived if the item is defective or we made the error.
- Installed or used parts can’t be returned — confirm fitment before you install.
- Special orders and custom items are final sale.
- Email us for return authorization before shipping anything back.
Full details: Shipping Policy · Refund Policy
