Where'd I hear all that? Umm...*scratches head*...here and there
The induction and exhaust stuff is all basic engineering principles (see below!); as for insurance, "performance" exhausts make your car noisier and thus more attractive to thieves, and are an indication of "boy racer"-type drivers which insurance companies see as a higher risk. Hence if you tell them you have these mods, they increase your premium; if you don't and you have to claim, they'll refuse to pay out :O
Induction kits are less restrictive to airflow than a standard airbox and filter, so the engine doesn't waste as much power (and therefore petrol) in sucking air into the cylinders. In normal driving, a car with an induction kit needs a slightly smaller throttle opening than one without, thus consuming less fuel. Under full throttle, an induction kit allows more airflow into the cylinders, hence more fuel is injected and more energy is released.
A well-designed free-flowing exhaust should also improve your MPG under normal driving as it reduces the back-pressure in the exhaust system, and consequently less energy is wasted in pushing waste gas out of the cylinder.
Of course, if you fit these tuning bits then thrash it everywhere, of course you'll not gain any MPG! But if you're driving normally your car will run a little more economically
There ya go Evil buddy...if nothing else it's conclusive proof that I spent far too much time awake in Physics lessons [8D]
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Fart In A Tin
<font color="orange">1994 Punto 55SX, metallic red, small, Italian and beautiful! </font id="orange">
