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This question is very multi faceted because fuel economy is such a complex topic. When a car is starting first the computer check the coolant temperature sensor to see how hot the engine is. In the memory of the computer there is a look up table that dictates how much fuel it should add for a specific temperature. This table is very conservative and the ...


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No, the engine speed at which maximum fuel efficiency is obtained is different. In fact, the faster you go in any given gear the worse the resultant fuel economy will be because it takes increasingly more power to overcome the vehicle's drag forces. It worsens because the power required to overcome drag forces on a vehicle at a constant speed is ...


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The short answer is no. The engine is most efficient at the RPM when maximum torque is achieved. It's easiest to explain with a picture. Power is a function of torque and RPM. Maximum torque is achieved because the engine is able to move the maximum amount of air and fuel in and out of the engine. The power continues to climb even when the torque starts ...


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This is the calculation you're looking for. IMAP = RPM * MAP / IAT MAF = (IMAP/120)(VE/100)(ED)*(MM)/(R) Where manifold absolute pressure (MAP) is in kPa, intake air temp (IAT) is in degrees Kelvin, R is 8.314 J/°K/mole and the average molecular mass of air (MM) is 28.97 g/mole. Note that, in the above formula, the volumetric efficiency of the (4-cycle!) ...


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Modern cabriolets have similar consumption numbers with the roof up or down. But that being said, a cabriolet version of a vehicle model would normally weigh more because of all the extra reinforcement needed to stiffen the body in the absence of a stiff roof. This means that e.g. the VW Golf V 2.0 would weigh let's say 1400kg and the VW Golf V 2.0 Cabrio ...


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Typically if you're doing any kind of speed, roof up with be more aerodynamically economical although I personally didn't notice much difference on either of mine. That said, I didn't pay much attention to fuel consumption in either of those cars.


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First you need to look at all parts and how they work. MAF- uses two different sensors to regulate how much fuel goes into the motor based on the TEMPERATURE and AMOUNT of air going to the motor. MAP- only measures pressure not the temperature. This is pulled from the IAT which measures intake air temperature. That being said how a MAP based system ...



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