oem intercoolers

[powerandtorque]

Im not sure its worth giving a car extra power if your not going to use it lol

It's all relative isn't it? I suspect that you'll find that the time that you actually spend at full revs/load is surprisingly brief and most driving will be at light load.

Providing that you maintain/service the car appropriately and drive with a degree of mechanical sympathy then I'm not convinced that a Stage 2 tune will cause any excessive wear and tear nor cause a healthy example to become unreliable.

What it will do however is highlight parts that are getting worn / tired and simply can't cope when asked to deliver so much above and beyond what the engine was designed/rated for - the youngest 306 HDi is now nearly 12 years old remember and most have well over 100k miles, often with patchy service history and penny pinching (if not neglectful) former owners.

The standard clutch is the well documented one, but you can potentially expect issues with the low pressure lift pump, the high pressure injector pump, and the turbo if they're tired. The engine itself seems to be pretty hardy at Stage 2 levels by all accounts, other than occasional valvetrain problems if exhaust pressure gets too high from pushing it too hard on the standard (restrictive) turbo.

Obviously a shoddy job fitting the intercooler will give issues with boost hoses popping off or leaking, but that can hardly be blamed on the car.