Stage 1, 2, and 3 modifications are often used by tuning businesses. Part manufacturers do not have a clear distinction or definition between stage 1 modifications, stage 2 mods, and stage 3 mods.
However, we have created this article to explain what mods and upgrades typically falls under these various stages of tuning.
Sometimes you may hear or read stage 1+ or stage 2+, these are usually describing modifications in between stages, such as BOVs or additional upgrades. For example, in our tuning guides you may see some mentions of these stage 1+, stage 2+, etc.
A stage 1 mod may normally be installed without the need for any additional components. Further than maybe some mounting bolts or clips, a genuine stage 1 modification item does not need any other engine changes to perform correctly.
Other modifications will assist in realising the mod's full potential, but they are not necessary. In terms of total advantages, they are toward the lower end of the tuning spectrum. They are less expensive and often simple to carry out.
Stage 1 modifications are typically straightforward to install, and should work on a normal engine. A simple remap is an example of stage 1 upgrade. Other examples of a stage 1 is a drop in panel filter or a cone filter.
Stage 1+ is also sometimes used. These typically entail modifications between stage 1 and 2, or additional upgrades to a stage 1 remap, such as a performance cold air feed, etc.
Stage 2 modifications are typically more expensive and in-depth than stage 1 mods, yet they only provide usually 20-50% of the power increase as a stage 1 remap would (in the case of forced induction vehicles).
However, if you want them to perform consistently or at all, they will almost always need extra labour or components. Some of the preceding examples might be considered stage 2 modifications if they are more sophisticated or provide greater power boosts.
Modifications that are common in stage 2 include the following.
A performance exhaust
De-cat or a sports catalytic converter
Full induction kit
Stage 2+ modifications usually are additional supportive mods, such as blow off valves, wastegate actuators, bigger boost piping, larger throttle bodies, camshaft upgrades, etc.
Usually a stage 2 or stage 2+ mod is improving the power without adding or changing forced induction.
Stage 3 modifications typically involved changing the forced induction, such as increasing the size of the turbocharger or adding one. It could also mean engine modifications, though these may even fall under a stage 4/5 by some tuning companies.
Most people agree the progression of mods and upgrades shown in this article is about right.