racing transmission
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racing transmission
<TABLE id=Table19 cellSpacing=0 cellPadding=2 width="100%"><TBODY><TR><TD vAlign=top>It's often said that the moment of inertia of the transmission is very important to a light, racing car. So important that shaving a pound off the transmission rotating part is going to do more good than shaving a pound off the vehicle body. Can someone explain? Is it really significant?
Another thing I've noticed is that a lot of racing cars and motorcycles have gear ratios that are very closely spaced. For example, a lot of those Japanese road bikes may have a 5 speed transmission with a overall ratio span less than 3 or 2.5. (if you divide the tallest gear by the shortest, they are usually less than 3). Why is this?
Does anyone know the gear span (and ratios if possible) of a typical F1 car or Rally car?
Thanks
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Another thing I've noticed is that a lot of racing cars and motorcycles have gear ratios that are very closely spaced. For example, a lot of those Japanese road bikes may have a 5 speed transmission with a overall ratio span less than 3 or 2.5. (if you divide the tallest gear by the shortest, they are usually less than 3). Why is this?
Does anyone know the gear span (and ratios if possible) of a typical F1 car or Rally car?
Thanks
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From: Northern MD
When you're racing, every little bit helps. A.J. Foyt used to qualify at Indy without third gear, just to get an edge. Gear spacing is dependent upon the torque or horsepower curve of the engine. For an engine that has a very narrow torque or hp peak, you want the gearing to take the engine slightly beyond that peak, but not drop too far below it when shifting to the next gear. It's all about keeping the engine speed where you need it most.
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Oh Oh, another mathematically complicated subject,
Plainly put, Inertia is the tendency for an object to remain at rest if it is not moving or to continue moving at the same velocity if it is moving. It takes power to get your truck moving, but once up to speed it will coast a long ways in neutral before stopping. This is inertia. If there were not friction (Air, bearings, etc) your truck would continue to coast at the same speed indefinitely. The higher the mass (weight) of the object the higher the force required to move it or change the velocity. Think of moment of inertia as the rotational equivalent. However, once the object is rotating you have the actual mass to resisting change (like the truck moving in a straight line) and the rotational force. The rotational force causes the calculated mass to increase as the square of the distance from the axis. A light object rotating in a large diameter circle can have the same apparent mass as a heavier object rotating in a much smaller circle. Think of gyroscopes or putting a lighter flywheel in your car.
Plainly put, Inertia is the tendency for an object to remain at rest if it is not moving or to continue moving at the same velocity if it is moving. It takes power to get your truck moving, but once up to speed it will coast a long ways in neutral before stopping. This is inertia. If there were not friction (Air, bearings, etc) your truck would continue to coast at the same speed indefinitely. The higher the mass (weight) of the object the higher the force required to move it or change the velocity. Think of moment of inertia as the rotational equivalent. However, once the object is rotating you have the actual mass to resisting change (like the truck moving in a straight line) and the rotational force. The rotational force causes the calculated mass to increase as the square of the distance from the axis. A light object rotating in a large diameter circle can have the same apparent mass as a heavier object rotating in a much smaller circle. Think of gyroscopes or putting a lighter flywheel in your car.
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Thanks.
Can anyone tell me the typical gear width (in the transmission) for a car with a torque of 200 ft lb? I'm trying to do a calculation on rotational inertias. Also it'll be nice if you can give me an "average" of the all the gear diameter. just a rough ball park
Thanks
Can anyone tell me the typical gear width (in the transmission) for a car with a torque of 200 ft lb? I'm trying to do a calculation on rotational inertias. Also it'll be nice if you can give me an "average" of the all the gear diameter. just a rough ball park
Thanks
