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      09-14-2017, 03:40 AM   #36
chris719
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Drives: '08 M Roadster
Join Date: Oct 2007
Location: NJ

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Quote:
Originally Posted by Tracus View Post
Speed is the engine's spin rate (RPM)
Torque is how much twisting force the engine generates at its shaft for a particular speed of rotation (Torque = Force x Perpendicular distance -> Nm)
Higher torque means better acceleration. The more available torque at lower speed, the better. If you want an engine to spin faster, you have to give it more torque. HP is a product of the torque.

Since you are mentioning a passenger car (not even a sports car - no trunk, no radio, no excessive weight, etc.) I believe that this car is stunning. A passenger car has 4-5 seats, a trunk, etc.
A gas vehicle needs to stay all the time at high Revolution to achieve a certain torque, while the diesel has the torque available instantly and effortless. At around 5000 RPM, torque and HP are equal. At any RPM below 5000, the value of torque is greater than the value of HP; Above 5000 RPM, the value of HP is higher.

Gas car stays sharp and nimble as long as you are on top of the game. It requires permanent attention and peak time with proper gear choice. -> more gas, less fuel economy.
Diesel has a linear torque curve, it's power line is pretty much stable and available anytime you need it -> better fuel economy.

You get more energy from 1 liter of diesel and diesel gets a hell of a lot better mileage than gas cars.
Just add more weight and the gas car will loose the game, while diesel will run pretty much the same. If you need acceleration, the torque is the one that will give it to you.

Sorry, Power DOES NOT reflect the capability for acceleration much better.
Power is related to the top (higher) speed while the torque is related to the Acceleration. The more Torque your engine generates, the more quickly your car accelerates.

we can't ignore the advantages of a diesel. If you drive a lot, diesel should be the first choice. Is relaxed, powerful and extremely efficient engine, that will also have a better longevity than gas engines.

PS
M3 and G30 are two different animals.
You should understand the concepts before you comment. A water wheel can generate tons of torque but its not very helpful due to it's angular velocity being so low. The torque that moves your car is the torque at the wheels anyway, not the crankshaft. There are many explanations and tutorials available online that have correct information. Hint: gearing

Last edited by chris719; 09-14-2017 at 03:46 AM..
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