Verified answer

A supercharger is driven by a belt connected to the engine. As it turns, it compresses air and forces it into the engine. More air needs more fuel. The two combined make more power. Your engine can only suck in so much air, unless that air is under pressure, then it can get more. However, a supercharger being belt driven takes a lot of power to turn. The faster the engine is turning, the more power the supercharger needs to turn. On the plus side, it provides instant boost, unlike a turbo.

A turbo charger does the same thing, but it has a second wheel that exhaust gases go around (like a windmill), to spin it. This wheel is connected to the compressor wheel to force more air into the engine. This design does not use engine power to turn the compressor, it uses the hot exhaust that was on it's way out the muffler anyway. However, it takes time to spin it up to speed for it to make boost.

Some manufacturers have started using two tiny turbos because they can spin up faster than a larger one, like in the 135/335/535. Two small ones make the same boost as one bigger one, but spin up faster. There are also variable geometry turbos that can be good for low and high speed. Back in the 80's turbos took a long time to get up to speed, this was called turbo lag. The engine would have no power and then all of a sudden it would have a lot.

Turbos require complicated exhaust plumbing and superchargers require space at the front of the engine so that it can be belt driven. They both have pros and cons. I have owned both, I preferred the supercharger, but that's only because the turbo car I had was an 80's with a lot of turbo lag.

Both dramatically heat up the air which can cause problems with pre-ignition. Without cooling it back down (which takes up more space) boost is limited. The more cooling you have, the more boost you can have. This is called the inter cooler. Although technically it is an after cooler, since it is after the compressor. An inter cooler cools off air before it is compressed. Either way, most manufactures use air to cool down this air, but some use radiator fluid, and some use a separate water system which is itself cooled off by air.

Oh and technically a turbo used to be called a turbo supercharger. But since some racing applications actually use both, it got shortened to just turbocharger. Also some applications use twin turbos of different sizes, one for low speed and either both or the other for high engine speeds.

These days all diesel engines use turbos and some piston airplanes also use them. In an airplane, the turbo spins faster as the aircraft climbs, to maintain sea level altitude conditions as long as possible. The engine doesn't lose power due to the altitude up to a point.

That is a small turbo, with a tiny intercooler, only suitable for a car of up to about 1.6 or 2 litres. I would never bolt a turbo onto an engine, you have to do a lot of machining work, such as lowering the static compression ratio of the engine, and you are asking for more power, so you must expect a shorter engine life. I don't agree with turbos anyway. They all have some degree of lag, run badly 'off-boost', create a massive hot-spot in the already hot under-bonnet environment (heat is a massively bad thing to have in a car) and only give the goods at higher revs... Superchargers are a much better bet. If they fail, the engine still runs. Don't produce a hot-spot. Act like a much larger engine through the rev-range. For your car, you would need a larger Eaton supercharger, and a good sized intercooler, possibly larger injectors and fuel pressure regulator, and water-methanol injection system. Power, torque and reliability.

Here is a link for you.

The 328 has a 3.0 liter inline six engine with 230 HP. The 335 is the same engine but has a turbo charger that takes it to 300 HP.

If anyone asks, all they need to know is that the turbo adds 70HP over the non-turbo version.