The S55 in the F80 M3, F82/F83 M4 and F87 M2 Competition and CS responds well to modifications, but it has a few known weak points once boost goes up. This guide explains the order we'd usually do things in, and why.
1. Charge pipes: do these first
The factory charge pipes carry boosted air from the twin turbos to the top-mounted intercooler. They're plastic, and they're a well-known failure point on tuned S55s. When one splits, the car loses boost immediately and usually goes into limp mode.
Aluminium charge pipes remove that weak point. They're a relatively cheap part, so we treat them as insurance before any tune. We stock two versions:
- Project Gamma aluminium charge pipes
- Project Gamma charge pipes with J-pipe, which also replaces the factory J-pipe section
2. Tune
A tune is where most of the S55's extra power comes from. A stage 1 tune on otherwise stock hardware is the usual starting point. Hardware like downpipes then lets you move to a stage 2 map. The same hardware can suit different maps, so tell us what you want from the car and we'll recommend the right combination. See our technical guides for more on how tune stages work.
3. Downpipes and intakes
Downpipes replace the restrictive factory sections straight after the turbos. They're the biggest single hardware gain on the S55 and they change the sound noticeably. Most people fit them with a tune in one visit.
- Project Gamma S55 downpipes
- S55 downpipe and tuning package, which bundles the hardware with the software
- Project Gamma S55 intakes with filters
4. Cooling
The S55 cools its charge air with a water-to-air intercooler. On a hot day or a second track session, that water heats up and the car pulls timing, so you lose power exactly when you want it. This is called heat soak.
A chiller system uses the car's air conditioning to chill the intercooler water, keeping intake temperatures down lap after lap. It comes in versions for R-134a and R-1234yf air conditioning, so we check which gas your car uses before ordering.
5. Handling
Once the power's sorted, adjustable drop links are a simple way to remove preload from the sway bars after lowering or corner weighting:
- Suspension Secrets front drop links for F80/F82 and rear drop links
- Front drop links for the F87 M2 and rear drop links
Suggested order
| Step | Parts | Why |
|---|---|---|
| 1 | Aluminium charge pipes | Removes the most common failure before adding boost |
| 2 | Stage 1 tune | Most of the gain for the money |
| 3 | Downpipes, intakes, stage 2 tune | Biggest hardware step; fit with the tune |
| 4 | Chiller system | Consistent power on hot days and track |
| 5 | Drop links, alignment | Sort the chassis to match the power |
Not sure where your car is up to? Send us your model, year, VIN and current mods and we'll suggest the next step. Everything above can be supplied only, or fitted at our Stepney workshop.