What is the purpose of having the engine in the back of the car, and why do only sports cars have it there?

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What is the purpose of having the engine in the back of the car, and why do only sports cars have it there?

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I don’t know why it is, but it isn’t quite true that only sports cars do. The VW beetle (the original at least) had the engine in the rear too.)

Having the engine in the rear adds more weight to the rear tires, which helps with acceleration but it makes the car more vulnerable to oversteer(to spin out).

It’s all about weight distribution.

Of the few that have it in the rear, it’s so the weight of the engine keeps the rear wheels touching the ground and giving you better grip.

Really, most sport cars have their engine in the middle of the car, between the front and rear wheels. This means that during tight turns all the wheels are on the ground, the back won’t kick out, and the front digs in where you want it.

Regular cars don’t need this because a family of four rarely does any high-speed cornering, and it takes up passenger/storage space.

Cars can be driven by their front wheels, back wheels, or both. Front wheels tend to be safer – especially for inexperienced drivers – as it allows for generally easier control. However, front wheel drive have a major downside. It has worse traction, which makes it worse in muddy or icy conditions, as well as racing. As such, many vehicles may be rear or all-wheel drives. Sporty cars especially like to be RWD.

Wherever the engine is, there’s a lot of weight. Whatever wheels have more weight have better traction. This means that an FWD car wants the engine in the front and an RWD car wants it in the back.

Additionally, an engine near the back can fly forward and crush the cabin (and the people inside) during an accident if the car is not built very sturdily.

There was an ancient sitcom where a woman was stopped and opened the hood and exclaimed, “The motor’s missing.” Her friend said, “That’s OK. There’s a spare here in the back.” I thought it was funny at the time, but it was a LONG time ago.

The early VW was quite light and the rear engine gave better traction, but the lighter front end could be problematic on an upgrade with the wind coming from the front. This happened on 101 N in Marin near Strawberry and Mill Valley.

Mr2 turbo owner here, the engine in the back helps massively with overall handling performance and grip. My car has no traction control but rarely loses grip due to the weight distribution,

The VW is by far the most well known in the US, but rear engine designs used to be pretty common for small economy cars. A rear engine layout gives you a lot of the advantages of a front wheel drive setup (a flat floor and easier assembly) without the engineering challenges of trying to transmit power to the wheels that also have to do the steering. Almost all of these cars used air cooled engines for obvious reasons.

Over time the CV joints and what not that you need to build a good front wheel drive car got a lot better whereas stricter emissions and customer expectations for long term reliability made air cooled engines less practical and so the rear engine economy car mostly died out. The one exception being the Smart car and its various knock offs.

As far as sports cars go, the only modern rear engine design I can think of is the Porsche, and I’d argue that this is mostly a historical fluke. Porsche started out building sports cars that took a lot of ideas (and even some actual parts) from the VW Beetle. Modern day Porsche enthusiasts are really invested in Porsche’s somewhat idiosyncratic design and the history behind it and largely regard the companies front engine designs as “not real Porsches”.