Bigger engine capacity, better Fuel economy?

[ideoteque85]

Can anybody confirm that with bigger engine, say M52 2.8L engine it has a better fuel consumption compared to that of M40 1.8L on combined highway and city drive? from what I understand, bigger engines use less power to move a given weight, thus less energy burned. does that make any sense?

 

[EuJax]

Hi there.

I heard and thought the same before but experience tells me otherwise though...usually its still the bigger CC cars will consume more in general usage. Maybe someone else could share as well?



Regards

 

[fabianyee]

If you study algebra in school, you'll understand the functions. There will always be an optimum point where the engine capacity would be the most efficient when mated to the chassis.. anything smaller would be underpowered for the car's weight and anything way above would be like killing an ant with a sledgehammer. However, have to see the engine efficiency of the engines you are comparing too. and also the engine tuning. Last but not least, the driving pleasure you'll get from the engine+chassis combo...

 

[jarance]

Sometime yes, sometime no.

If in town drive, smaller engine have better consumption. But in highway, the bigger engine have better consumption.

eg. 318cc = 520 to 540 km for 60 l and 325 = 560 to 600 for 60l for highway. but then again 318 is 15yrs old and 325 is 4 years old.

Driving habit play a lot in fuel consumption.

 

[infinityKL]

have to 2 318 and 1 328 in the family...

city driving almost the same 400(+ -) km's ... for all 3 cars..

 

[B33mEr]

I agree with bro fabianyee ... it all boils down to the engine and weight of the car.

 

[ideoteque85]

thanks for the response guys but i am still wondering whether my e36 with m40 engine fuel efficiency can be improved. asked one of my friends, he said that if I use bigger engine, I can get both power and fuel efficiency. guess I have to do more research.

 

[elixir]

it depends on your driving style. eg. If you drive in a highway with hard acceleration and braking. At an everage speed of say 160km/h for a same distance, a bigger capacity engine is better in terms of fuel efficiency due to its power. If you drive at a constant speed of say 100km/h, smaller capacity engine tends to be more efficient.

 

[RRRR]

if we ignore driving style and driving condition (ie city or highway),what is the optimum engine spec for a e36 4-dr auto?

can a sifu enlighten plse?

thks

 

[Eggie86]

it depends on your driving style. eg. If you drive in a highway with hard acceleration and braking. At an everage speed of say 160km/h for a same distance, a bigger capacity engine is better in terms of fuel efficiency due to its power. If you drive at a constant speed of say 100km/h, smaller capacity engine tends to be more efficient.

Haha. Yes. Driving style does play a key role. Like me, at times like to drive pedal to metal, especially when given a decent stretch of road and light traffic, so a full tank on the E32 will probably reach1/4 in about a week. Of course, need to consider mileage la. My car already almost 200K on the odo too.

Anyhow, sorry for deviating from the thread's nature, it's bout E36s anyways.

 

[astroboy]

Fact 1:
Each car of various engine capacity has its own optimum speed, bigger CC, optimum speed is higher, vice versa. If the smaller CC car is traveling at the bigger CC car's optimum speed, then the bigger CC car will run more economically, vice versa.

Therefore, at certain speed, even the V8 M3 can be more economical than the 1.5L Toyota Prius Hybrid.

Fact 2:
Bigger CC car is heavier by common sense, so if there's a lot of stop start traffic, moving a heavier car takes more fuel. Simple physic..

Let me give u a classic example reported in their catalog (combined cycle):

~ Wira 1.5L Manual is more economical than Wira 1.3L Manual
~ Wira 1.3L Manual is more economical than Wira 1.5L Auto..

.. but again, these are controlled environment test, meaning flat road, aircond off, window closed, cool morning temperature, neutral wind direction and velocity, less than half tank of fuel, over inflate tyre a little, single occupant, at speed no more than 55kph... drive a little faster with aircond running with cabin temperature set to 23 celcius, in a hot afternoon, with a passenger, I am sure the result can be very different.

Put a 1.3L engine in a Camry and I can pretty much predict the result with confident!

 

[hotfoo36]

Yah, astroboy, fact 1 was proven in top gear as well. It's a true fact.

 

[RRRR]

if we ignore driving style and driving condition (ie city or highway),what is the optimum engine spec for a e36 4-dr auto?

can a sifu enlighten plse?

thks

any kind sifu can advise wat is optimum for a e36 4-dr auto?

 

[astroboy]

any kind sifu can advise wat is optimum for a e36 4-dr auto?

What's your average speed? City roads or highway more often? (no need to answer.. I don't want to know.. )

Optimum e36 4-dr would be the 318i Manual, better FC than Perdana. If auto, avoid the 318i Auto, super under power, 325i auto is pretty optimum by my driving standards.. :wink:

 

[ideoteque85]

Im driivng the auto. the fuel consumption worries me every week. most of the time I drive very gently. but i think the traffic jam every day contributes a huge part on it.