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I see some track race cars, especially old ones made in the 1960s-70s, are designed with the heavy components of the car sitting between the rear wheels. In fact, some of old rear-/mid-engine cars use transmissions where the differential goes between gearbox and the engine to provide even closer engine placement to the center of rear axle.

What are the advantages of this layout, when the center of gravity is placed over the center of the rear axle?

From my understanding front wheel drive provides stability, so if the engine is placed at the rear axle does it providing better grip?

I see some modern track vehicles have the engine placed even farther back. Does this mean the older configuration is not as effective as they thought back in old days?

I learned that a car with instantaneous center of rotation goes further with slip from the rear wheels. Is this reason why they placed the engine at the geometric center of car in modern track cars?

Do cars with smaller engines perform better with the engines placed over the rear axle, or is this an illusion of longer wheelbases and smaller engines in modern cars?

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    $\begingroup$ There are large sections in Wikipedia about this. en.wikipedia.org/wiki/Automobile_layout $\endgroup$
    – hazzey
    Feb 17 '17 at 15:23
  • $\begingroup$ OK. thanks but i have read this before. so i see my curiosity comes from ignorance. I thought there should be more detailed answers. such as about rotational inertia formulas or something. but i see this is not the case. still im curious about what if a cars 99% of mass placed at the rear, with much of the down force placed at the front. i thought i could assume this with the answer. but i guess ill edit my question that way. $\endgroup$
    – hfc
    Feb 17 '17 at 19:58
  • $\begingroup$ or i may delete my question $\endgroup$
    – hfc
    Feb 17 '17 at 20:00
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One possible reason for placing the engine and most of the weight at the back of the car would be to improve rear wheel tire friction. This would be useful if the car has a rear-wheel drive, since the car's ability to accelerate is limited by the amount of torque the wheels can support before slipping.

Adding weight to the back of the car would increase the normal force exerted by the rear wheels on the track. Since friction is proportional to the normal force, increasing the weight in the rear will increase the friction, thus improving the acceleration of the car.

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