The internet uses Stage 1 to mean anything from a canned handheld flash to a built long-block, which makes the term almost useless when you are trying to budget. Here is what each stage means when we quote it at Apex, so you can compare our numbers against anyone else's on the same terms.
Stage 1 is software only, on an otherwise stock car. Factory turbo, factory intake and exhaust, factory clutch or torque converter. We custom-flash on the dyno rather than loading an off-the-shelf map, because the same engine code in Charlotte humidity behaves differently than it does in Denver. On most modern turbo platforms Stage 1 is worth 15 to 25 percent over stock and requires 93 octane. Expect it to be a same-day job.
Stage 2 is software plus the bolt-ons the software assumes: a downpipe or catted midpipe, a sealed intake, and usually an upgraded intercooler. The tune is written for that specific hardware. This is where you start needing to think about the clutch on a manual car and the transmission tune on an automatic, because factory torque limiters exist for a reason. Budget for two shop days and a return dyno session.
Stage 3 means the turbocharger itself changes, and everything downstream of that decision changes with it: fueling, often injectors and a fuel pump, usually the clutch or converter, frequently the axles, and always a new tune developed from scratch. This is a multi-week project, not a weekend, and the honest way to quote it is by target power rather than by stage number.
The budgeting advice we give everyone: decide the number you actually want before you buy the first part. Getting to a given power figure in one planned step is materially cheaper than arriving at it through three separate purchases, because at each stage you throw away parts that were correct for the stage below. Bring us the goal and the deadline and we will build the parts list backwards from it.
