Installation Instructions:
We are proud to offer a game-changing product for the S55 community! With this innovative solution we are able to push +38% more fuel flow out of the OEM HPFPs! We start with Genuine BMW vacuum pump cores and install our Dorch Engineering Cams within the OEM assembly using our proprietary manufacturing tooling and validation equipment. What you end up with is a ton more fuel flow in a very simple and clean package, all while utilizing the OEM HPFPs. Since the S55 engine uses some of the smallest fuel pump cams in the Bosch lineup, we are able to achieve this additional flow without sacrificing any of the longevity or reliability of the OEM pumps. There’s no cutting, no bending, no crimping, etc. This kit drops right in like factory and it does not require any special tuning to get up and running. All of the safety and sophistication of the stock DME remain in place.
S55 HPFP Flow Capacities
The table below serves as a reference for maximum fuel flow in cubic centimeters per camshaft revolution for various S55 fuel pump options.
| Pump Model | Fuel Flow (cc/rev) |
|---|---|
| HDP5 (Stock S55) | 1.527 |
| HDP5 w/ Dorch Lift Kit | 2.100 |
| Dorch Stage 1 HPFP w/ Lift Kit | 2.857 |
Software changes are NOT required to run this upgrade. However, we do have preset optimized maps available via Bootmod3 and MHD. Simply check the box for our “Lift Kit” upgrade when flashing.
NOTE: The S55 fuel system is very much limited by the injectors. In order to see the true benefits of this kit, it is highly recommended to upgrade to the larger EU5 Injectors.
Kit Contents:
- Dorch Vacuum Pump Assembly
- Vacuum Pump Sealing Cap
- Vacuum Pump Gasket
Kit Fitment:
F80 M3 – All Variants
F82 M4 – All Variants
F87 M2 – Competition, CS ONLY