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Originally Posted by karimbo
Does anyone know when has methanol been introduced in the serie as fuel and for what reason it has replaced "normal" gasoline ?
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I'm not sure on the histroy of methanol and when they started using it, but I'm sure it was about the time that the big turbo's and massive boost were introduced to the series. Methanol has a MUCH higher detonation point then gasoline and that is why it is used. Unlike Forumula 1, Champcars have turbos and they run ridiculous levels of boost, I think they use something like 42-44psi at road courses currently. A stock street car with a turbo(like say a WRX or something) probably runs something around 6-9psi(for comparison). Their are two problems about running that much boost(which is why a street car could never run with that much). First off, fuel delivery. 42psi is a HUGE amount of pressurised air being shot into the intake stream and into the combustion chamber. Without enough fuel to compensate for the air, the engine would run lean and ping and detonate until the engine was toast. No big deal for a champcar though, as they have massive fuel injectors, that most of us could never afford in our street cars. The other problem is that pressuring air creates massive amounts of heat. As the turbine compresses the air it gets very hot before continuing on into the intercooler, which as it sounds like, cools the air. But still the air is very hot comared to a street car, and then it gets mixed with the fuel which makes is very combustible. Then as the air/fuel mixture moves into the combustion chamber its gets compressed further. With the heat involved in a Champcar, if they used regular gasoline, as the piston moved up to compress the air before the spark plug ignited it(to push the piston back down of course), it would detonate(which is very different from combustion). This makes the engine lose power and is hard on the engine internals. Methanol, as I said earlier has a much higher threshold before it detonates. It takes much higher temparatures before it detonates, so the piston can fully compress the air/methanol mixture allowing it to combust when the spark plug ignites it.