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Hi, I'm new here but I was just wondering what the difference of power loss of a corvette over any other car? I know you kinda lose 10% to 15% of your Hp as it travels to the rear end but with Corvette, I wouldn't think would lose that much Hp since the transmission and rear-end are one unit so the power loss wouldn't be as significant as in your standard front-engine car am I right?
 

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am I right?
No.

Frictional losses are not a function of layout, they are a function of how the parts are designed. For example, the viscosity of the lube in the final drive probably has more effect on lost HP than the drivetrain layout. Modern cars are designed to minimize internal friction and power loss primarily to improve performance on the CAFE mileage test. This is why even manual transmissions today use ATF instead of 90 weight gear oil. The "compact" FWD layout was done more for packaging than efficiency. By making the drivetrain more compact, the whole car gets smaller and lighter for the same internal passenger volume. Body structure weighs less, so suspension can be lighter, brakes can be lighter, and thus a smaller, more efficient engine can provide equivalent performance. Sir Alec Issigonis demonstrated this with the original Mini.
 

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No.

Frictional losses are not a function of layout, they are a function of how the parts are designed. For example, the viscosity of the lube in the final drive probably has more effect on lost HP than the drivetrain layout. Modern cars are designed to minimize internal friction and power loss primarily to improve performance on the CAFE mileage test. This is why even manual transmissions today use ATF instead of 90 weight gear oil. The "compact" FWD layout was done more for packaging than efficiency. By making the drivetrain more compact, the whole car gets smaller and lighter for the same internal passenger volume. Body structure weighs less, so suspension can be lighter, brakes can be lighter, and thus a smaller, more efficient engine can provide equivalent performance. Sir Alec Issigonis demonstrated this with the original Mini.
Hot rodders fixed that by stuffing big engines in those small cars ! !LOL
 

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Moving the transmission to the rear end has less to do with power conservation than with vehicle front to rear weight distribution. The fundamental loses of the transmission and rear axle remain and are related to the number of gears tuning at any given moment, bearing type, quantity and quality, for an automatic the coasting friction of clutches and or bands not in use, and certainly the oil.

The trade is elimination of the driveshaft losses in the U-joints of a conventional live rear axle which vary with angle changes and alignments of the major assemblies at the ends of the shaft for U-joints in the independent axle shafts. These tend to have more U-joints than a live axle arraignment and they work at sharper angles which increase losses at the trade of better f/r weight distribution and better suspension control of the tire.

Here the trade is better handling for probably more drive line losses. But that is very design related. The early Corvette independent rear was very squirmy in a structural sense and not very efficient at controlling the tire nor the driveshaft. Through years of refinement the current design is much improved in dynamic control which usually also exhibit efficiency improvements in the preservation of power as well as handling.

The biggest installed power eater is usually the exhaust system. This is always a tough nut to crack as exhaust systems tend to be designed around what space is left after everything else is installed, this has been a long standing problem of the Corvette.

Bogie
 
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