Engine Placement of Small Hatchbacks

[bharathbigb]

Hello everyone,It has been a long time since I started a thread.Hope everyone are doing great here.

I have this doubt regarding small cars.Like,Very budget cars with small engines.There are small problems with the small car design

The Boot Space is very little and we can't really place more than full suitcase.

But I think there can be a solution for this,But also think why car manufacturers couldn't do it

Why won't the Engine sit completely in the Back and use the Front as the Boot ?

Since the front doesn't have any Engine there,There will be oodles of space in the front right ? Isn't this possible ? What are the drawbacks of this approach ? The ones I am aware is the Engine Noise protruding into the Cabin drastically reducing the NVH and will be quite irritating when cruising in the highway and you can hear the Engine screaming and another problem I am aware is that the Car might understeer a bit,Another thing I am aware is safety concerns if anybody rams in the back,The car is prone to catch fire or even explode,Another safety concern is that the front crumple zone strength is also reduced as the Engine could also act as a component absorbing the impact right ?

Thanks :)

 

[bhvm]

there are some rear engined hatchbacks. Nano being one of them. the idea of engine buzzing under rear bench is not liked by many people hence most car designers place engines in front only.

 

[balenoed]

All naturally aspirated engine requires sufficient amount of air flow to get a rich air-fuel mixture to run engine smoothly. Engines placed at the front get air very easily because of velocity which is not possible if the engine is placed at the back. For small engine like nano these theory might work. But bigger engine can not be placed at the back. If they want then they need to add costly equipment for forced air circulation and because of that the NVH level will high.

 

[bharathbigb]

All naturally aspirated engine requires sufficient amount of air flow to get a rich air-fuel mixture to run engine smoothly. Engines placed at the front get air very easily because of velocity which is not possible if the engine is placed at the back. For small engine like nano these theory might work. But bigger engine can not be placed at the back. If they want then they need to add costly equipment for forced air circulation and because of that the NVH level will high.

That's what I said,Budget Cars with very small 800cc-1 litre Engines.Couldn't they be designed to fit in the back ?

 

[balenoed]

NO. the amount of air required to do ignition won't be possible if it is placed at the back.
Also if it is placed at the back with forced air circulation the NVH level and cost will go high. I won't believe anyone will but an alto @ 5 lacs. Right? So in business point of view placing a engine at the back does not make sense.

One more thing is the vehicle CG. If it is placed at the back , to get the CG right manufacturer need to arrange other counterweight at the front. Else vehicle won't be stabilized. Also the wiring harness will be very much complicated owning the fact that the routing should be done all the way from back to front in dashboard. So in case of small issues you need removal of many part, service point of view its not that great. The only reason the engine was placed at the back of nano is the space management as they want to use the underseat storage. But the same thing may not hold good for 800 cc engine.

 

[bhvm]

the air issue Can be solved with a roof scoop/ side scoop and turbocharging.
serious issues are weight distribution, CG, Servicablity & nvh. of course price matters.

as you'll add engine in rear, you'll gain space in front but loose the boot in back.

overall, it's physics & there's no free lunch.

 

[balenoed]

the air issue Can be solved with a roof scoop/ side scoop and turbocharging.
serious issues are weight distribution, CG, Servicablity & nvh. of course price matters.

as you'll add engine in rear, you'll gain space in front but loose the boot in back.

overall, it's physics & there's no free lunch.

That's exactly the point. As you see the price of turbocharged petrol is very high. So even we can overcome all issues by placing the engine at back but no body will buy that car as the cost will be very high.