Engine size effects on petrol

[anywebsite]

This is a good site for comparing mpg and performance

 

http://www.whatmpg.co.uk/index.html

 

Diesels are generally much more efficient, and modern ones perform as well as similar sized petrol models

 

I have a focus 1.6 diesel tdci - £55 would easily get me £500 miles.

 

Here's the Astra details http://www.whatmpg.co.uk/Vauxhall%20MPG%20Information.html

 

They cost more too & don't save any fuel on short trips, so you'd need to do a lot of driving to ever see any saving. Under 40mpg is pretty poor to be fair, I get that usually driving round town in a 1.5 petrol.

 

Newer cars are generally more efficient, similar problem with the cost.

 

OP: If you're really only getting around 300 miles out of a 1.2 (I assume it's a pretty small car for that size engine) then you should look at how you're driving it, that will make a much bigger difference to fuel consumption than an extra 200cc or 400cc. They tend to use more when they're being driven hard, with a more powerful engine you wont need to work it as hard (or slow down as much), so you might even use less petrol with a bigger engined car, depending on how you're driving & the car.

Edited August 31, 2014 by anywebsite

[drummond]

I'm still on my first ever car which is a 1.2 petrol which costs me about £55 to fill which I get 300+ miles out of. I'm getting a new car ASAP but need information on the costs of fuel on bigger engines as I don't want another 1.2.

 

Been looking at 1.4 & 1.6 petrol astras and 1.7cdti, is there a big difference between 1.4 & 1.6 and how does the 1.7 diesel matchu up against them, want something more powerful than my little 1.2 obviously but don't want it to be guzzling fuel.

 

Don't take any notice of the official figures. If you find a car thats claimed to do 65mpg you'll be lucky if you see 50.

[medusa]

The answer to this is down to the sort of driving you're going to do as well as the speed you travel, the heaviness of your right foot and a whole load of other factors, just as much as the efficiency of the engine.

 

A 1.6 will struggle less at motorway speeds than a 1.2, but part of that is down to what speed you call 'motorway speed', the terrain of the motorways, whether you like overtaking or not and whether your car has 6 or 7 gears or just 5.

 

My car can get 300 miles out of a tank of diesel if I'm doing mostly short local, low speed journeys or 600 miles out of a very steady long journey with lots of cruising in 7th gear.

 

There's just no way to quantify the outcomes around all of these possibilities.

[Xt500]

Iver never owned a diesel that would do less than 500 miles to a tank.I wouldnt have a small engined car given,its hard work and they eat fuel.You get crap brakes on a small engined car too.

Every diesel will be alot more powerful than your 1.2

[buck]

My 2.4 litre Hyundai Sonata gets from 24 MPG to 35 MPG US gallons, which are smaller than the old UK gallon was, depending on what klind of driving It is very comfortable, even on a 500 mile single day trip. Cruise control helps a lot.

[Aleksandr]

Depends on the type of driving you will be doing,the bigger engines can work out more economical than the smaller engine for motorway driving.

Not quite true, but the differential in consumption lessens to such an extent at higher speeds that the bigger engines are worth the relatively little extra fuel that they take.

 

---------- Post added 31-08-2014 at 20:46 ----------

 

Don't take any notice of the official figures. If you find a car thats claimed to do 65mpg you'll be lucky if you see 50.

It depends. If you accelerate rapidly and drive in the highest gear that the engine is happy in, i.e. when it can still accelerate and isn't labouring, you should meet those figures. Engines are at their most efficient when the throttle's fully open, so don't dawdle in getting up to your target speed or you'll waste fuel.

 

Another top tip is to accelerate on your way down hill and lose speed on your way up. (You only need to bother near the crests and troughs on long hills.) A lot of people think they can get better fuel consumption by using cruise control; however, it keeps speed constant, and on hilly terrain, that uses more fuel.

 

Also, try driving when the roads are quieter.

 

I have always been able to beat the official fuel figures when I do this. Keeping speed down, and certainly below 56mph really helps. However, it takes a lot of effort, so like everyone else I rarely bother!

[Aleksandr]

Iver never owned a diesel that would do less than 500 miles to a tank.I wouldnt have a small engined car given,its hard work and they eat fuel.You get crap brakes on a small engined car too.

Every diesel will be alot more powerful than your 1.2

Every diesel will be more 'torquey', not necessarily more powerful. Mileage depends on tank capacity, so that doesn't give a good indication of fuel efficiency as some tanks are bigger than others. I disagree about the brakes - that's obviously not true if you look at the official stopping distances. Smaller cars do not eat fuel any more than larger ones, obviously. Hard work? Yes, they can be hard work sometimes, but parking can be so much easier!

[mazeppa]

At 19 years old you should be looking for something that'll pull a bird, not fuel economy.

[geared]

I drove a Mk5 1.7 CDTI Astra and it was really horrid to drive, the engine was totally gutless when the turbo wasn't on song, the interior felt cheap and nasty and the ride in general was rubbish.

The 1.4 was pretty crap as well come to think of it.

[skat man]

Can't be bothered reading it. I get the just. ... Two people running along the motorway. One with long legs one with short legs. Short leg is working two times as hard compared to the long leg Dood. Big engine on a motorway will not break a sweat. The pistons move slow and steady. Less fuel. The short leg ( small car) Pistons going up an down like a loony , More fuel. >>> if you drive to the local shops, go small, If you do motorway go big!. >> Big will use more fuel going to the shops, And small will use more fuel on motorway!.

 

---------- Post added 01-09-2014 at 02:05 ----------

 

For a good compromise get hold of a 1.7 turbo diesel.