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I swapped my 2006 1.4 Corolla for a new 1.33 Auris (with six speed gearbox and stop/start technology) just over two years ago. Differences include the Auris having a bigger and more roomy body, approx 1 second slower to 60, 6 mph off the top speed, but more economical and less car tax. The bhp of the 1.33 engine is the similar to the previous 1.4 (101 as opposed to 100bhp), and the difference in engine size is 69cc. The smallest engines on offer in some rivals start around 85bhp (Focus, Golf, Astra).
The Auris is more economical both around town and on a run than the Corolla - eg up to 42mpg for the Corolla and up to 49mpg for the Auris (two people on board, rear seats folded and loaded to the window line with luggage, including motorway work). The 1.33 is a very light, sweet-revving engine and does need a few more revs than the Corolla for brisk progress - although never appearing obtrusive. Motorways - inclines sometimes need a change down from sixth to fifth, otherwise fine (but this is more to do witrh the gearing than the engine).
It is the same engine as in the 1.33 IQ, Yaris and Urban Cruiser.
We also have a 2007 Mazda 2 1.4 - based on the Fiesta/Fusion and built by Ford in Spain. That provides quite perky performance and handling, whilst being quite commodius for the size of car - almost as practical as the Jazz.
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Yup, nice big V8s would be nice-but realistically, it isn't going to happen.
Doesnt mean we need to be putting food blender motors into big chunky cars though does it? Ive always thought a small engine in a big car is a stupid idea but its hardly a new idea. The Cortina had a 1.3litre variant which now in 2012 has only just made it out of the Ford of Dagenham car park.
People buy these big cars because they have families and they buy them with small engines in the belief they'll get fuel economy and usually pay a mammoth premium for its small engine status and they're such a picture of depression when i see them driving along getting only 5mpg more than i do in my large 3.0litre luxury beast and they probably paid more for their car as well.
Remember the discussion in the Mini thread about how my mpg is not a million miles from the poorly performing Mini? I still think a large part of that is because my car can do 70mph essentially on tickover and the engine rarely has to work hard.
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Having spent 40 years buying mid-range Ford and Vauxhall models it was always true that real-world fuel consumption was little different between the smallest and largest engine - it takes a fixed amount of energy to propel a given car body at a given speed, so no surprise - in fact the difference in fuel consumption was no doubt due entirely to the fact that the performance of the larger engine was hard to resist sometimes.
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Oh, I dont know, pumping losses with Extra cylinders, extra weight , not to mention the performance, etc etc.
But yes indeed an undersized overworked engine was/is not efficient.
But then I would never have bought one, ri.e. a car with an undersized engine.
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unthrottled, isn't the main advantage of a chain that its highly unlikely to break and you don't have to change the blooming thing at intervals, generally less than manufacturers recommend?
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If chains are starved of oil, they will suffer. They tend not to break-but they do stretch which can be just as damaging if piston-valve clearance is marginal. A lot of chains start getting rattly by 120,000 miles.
I think Ford are on 100,000 mile intervals for some of their belt engines. So if you're likely to have to change both a belt or a chain once over the lifetime of the car, then the belt wins hands down because it is cheaper and easier to do. The days of 40,000 mile belt changes are long gone.
Chains are great when they are very short ie on pushrod engines-but apart from Chevrolet's small block, you don't see many of them any more.
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If you want a small petrol engine that you have to work hard, buy a Mazda RX-8 :-D
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Bobbin, you'll more oil in a RX8 than petrol!
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I know. I wouldn't buy one in a million years! Shame as they're nice to look at and the experimental nature of the rotary engine appeals to me. w***els!
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If you want a small engine that you have to work hard, buy a Mazda RX8.
Interesting. There's no agreement on how to define the displacement of a w***el. The problem is that the output shaft spins at three times the angular speed of the rotors. However, each cycle is completed in one revolution of the rotor compared with two revolutions of the crank for a four stroke piston engine. I still prefer to think of the w***el as a large displacement engine spinning slowly, rather than a small engine spinning quickly.
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it takes a fixed amount of energy to propel a given car body at a given speed
No-it takes a fixed amount of power to propel a given car at a given speed. Unfortunately, engine efficiency always falls as the load is reduced, so a big engine at low load will give poorer economy than a small engine at high load.
In the past, small engines could only make power by revving hard-and they usually hard short gearing.Revving is what kills economy
With a turbo, you can gear a small engine similarly to a larger naturally aspirated engine.
the fact that the performance of the larger engine was hard to resist sometimes.
Absolutely.
Edited by unthrottled on 03/01/2012 at 17:31
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unthrottled, I believe Alfa cam belts should be at 36,000 miles while VAG diesel is 50/60,000 miles. That's a few times in the life of the car. We changed our A6 diesels at 50 with waterpump. The last one went up to over 280,000 before we let it go.
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I believe Alfa cam belts should be at 36,000 miles
Well, it is an Alfa!
The PD engines started with very conservative intervals due to the high stresses caused by the unit injectors, but the intervals gradually increased.
The CR rail engines that are belt driven should have long intervals ~100k.
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Unthrottled - I always thought the general feeling was that chains were a safer option than belts, however I am no mechanic so maybe not.
I'm starting to think that other than regular servicing and treating a car with respect what you need more than anything else is blind luck to have a cheap reliable car
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Chris-the general 'feeling' is that a chain is safer than a belt because a chain sounds stouter than a rubber belt. But, nowadays, I don't think it's true.
Blind luck plays a big part. If you've got a car that works, and you can't afford big repair bills-better to leave autotrader on the shelf!
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Back to the small engine in large car query, I wonder how the 1.6 TDci diesels cope/work in cars such as the Mondeo and Citroen C5?
Part of me thinks that they must have to be worked very hard, therefore limiting performance, especially when needing to escape or avoid "situations", and therefore, economy must struggle, compared to a more relaxed 2 litre?
Then another part of me thinks back to the days when you had petrol 1.6 engines in Cortinas/Sierras/Cavaliers etc which seemed to make good progress., although back then, fuel economy and VED prices were not such issues as nowadays.
The modern cars above benefit from low VED but I wonder whether you finish up spending perhaps more on fuel compared to a 2 litre.
Too many thoughts?!
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Downsizing a diesel doesn't yield the same benefits as downsizing a petrol.
A 1.6 diesel is quite a small engine for a Mondeo which is much heavier than an old cavalier or Sierra.
Part of me thinks that they must have to be worked very hard, therefore limiting performance, especially when needing to escape or avoid "situations", and therefore, economy must struggle, compared to a more relaxed 2 litre?
Hmm? 35 horsepower should be good for cruising at 70mph. A 1.6 TDCi can produce that at 1500 RPM. Not revving very hard at all. Use a different gear to accelerate as you do for cruising. Simples.
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Wife had a 1.6 TDCi C-Max, 108 BHP. Plenty of power for normal use and excellent economy but overtaking needed either a very clear view or balls the size of a cart horse, no spare power at all for emergency use even if you were in the correct gear. The 2 litre Mondeo and BMW Turbo Diesels have loads of power and you never feel shortchanged or exposed when overtaking. Know which I prefer.
Having said that wife now has a Ceed with 1.6 CRDi and 115 BHP, feels about as quick as Mondeo, loads better than C-Max.
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The Kia Rio never feels short on power.
107BHP in a 1200kg package works out at 90BHP per ton.
however the BHP is not so important on a diesel, its the torque that is more important.
and 176ft/lb is plenty for overtaking when needed.
The only problem with smaller diesel engines is that it HAS to be driven on boost.
Off boost there is nothing there.
Fortunatley todays small diesels with turbos have a low rev point where the turbo comes in fully.
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BHP is not so important on a diesel, its the torque that is more important.
Hate to be a pedant, but that's not true-power is the only thing that matters, since the gearbox can multiply torque to any required value- but you can't multiply power.
The confusion would go away if they simply published a Power vs RPM chart.
The driver doesn't need to know how much torque he has available, he needs to know how much power he has available at a given RPM.
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At work our pool cars are 90hp 1.6TDCI Focus Estates. Not only are they miserable for overtaking, or going up hills, but overtaking is as someone said, a mission of faith. Some fag-packet maths using the log books in the cars, they're only getting between 39-44mpg over approx 20k.
I was recently subjected to a new model Astra 1.4 SRI. That was an exercise in futility. Driving in the car on my own, I attempted to pass a truck on a crawler lane while crossing the Pennines. Flat out in 3rd at 50mph, the Astra was physically unable to pass the truck and I had to brake and duck in behind the truck again to let the furious drivers behind me pass. Even an old granny in a Micra went speeding past me. The Astra got 29mpg average according to the computer across the 200 mile round trip.
My own car is an old 1.8 petrol Mk3 Mondeo. It's far better to drive, with consistant power, and can even overtake up hills. It gets 32mpg around town and over 40mpg on long motorway runs. But the road tax is £200+ a year as the government think it's a polluting car. I think the 1.4 Astra pollutes more as it uses more fuel, yet it only gets a £30 tax bill yearly.
Makes no sense to me.
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The Astra 1.4 Turbo makes more power than the 1.8 Mondeo engine and at lower engine speeds. OTOH, a small naturally aspirated engine in a heavy car will always be hard work.
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The Astra 1.4 Turbo makes more power than the 1.8 Mondeo engine and at lower engine speeds. OTOH, a small naturally aspirated engine in a heavy car will always be hard work.
This didn't have a turbo, though. Big heavy Mk6 Astra with a Corsa engine, good choice.
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To be totally pedantic engines do not produce power, they produce torque which is easily measured. Problem was and still is no one understands torque thus a formula was derived that converts torque to horsepower since although horsepower cannot be measured everyone understands it, they can visualise 120 horses, who can visualise 180 lbs/ft of torque. The formula is BHP = (Torque(in lbs/ft) x engine speed)/5252 eg an engine that produces 180 lbs/ft of torque at 2000 revs is producing 68.5 bhp at 2000 revs. By simply reversing the formula an engine that produces 115 BHP at 4000 rpm produces 172 lbs/ft of torqe at 4000 rpm. Applies to petrol and diesel engines.
These fancy Rolling Roads that do power plots do not measure BHP, they simply cannot, they measure torque and the electronics convert it to power because that is what people want to see and can understand.
I would rather have an engine that produces a good spread of torque than one with peaky power any day, that's why modern diesels are such a pleasure to drive and why modern small high revving 16 valve petrols are a pain on a day to day basis. Modern low pressure turbo petrols like the VW TSI, Ford ECOBoost and Peugeot THP are absolute crackers since although they don't have massive bhp they have an even better spead of torque than a diesel.
Used to race many years ago, quite sucessfully. There was a saying amongst the sensible in the paddock, power sells engines, torque wins races. Still applies today.
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Used to race many years ago, quite sucessfully. There was a saying amongst the sensible in the paddock, power sells engines, torque wins races. Still applies today.
A glossy car magazine cliche, utterly without merit. What moves your car is tractive effort. The tractive effort is dependant on power. Engine output torque is totally irrelevant.
The driveshaft cannot tell the difference between an engine producing 100lbf.ft of torque at 5000RPM and an engine producing 500lbf.ft@ 1000RPM. The tractive effort is the same.
An engine with a broad torque curve is easier to drive because it makes more power across the curve.
Edited by unthrottled on 05/01/2012 at 11:59
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A glossy car magazine cliche, utterly without merit. What moves your car is tractive effort. The tractive effort is dependant on power. Engine output torque is totally irrelevant.
The driveshaft cannot tell the difference between an engine producing 100lbf.ft of torque at 5000RPM and an engine producing 500lbf.ft@ 1000RPM. The tractive effort is the same.
An engine with a broad torque curve is easier to drive because it makes more power across the curve.
...which is why, I guess the Porsche 911 turbo that I saw regularly in the mid 80s only had a 4 speed box owing to the fact that the engine could provide a much wider torque band and didn't need the 5 speed box that the cheap imitations boasted.
Edited by Hugo {P} on 06/01/2012 at 01:34
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Believe what you want, textbooks to prove it.
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No textbook will tell you that "torque wins races". Certain types of racing certainly prefer constant torque curves, or in WRC constant power curves, but most simply favour maximum power, and a narrow powerband, relying upon the driver to keep the engine in that band.
Torque on its own is nothing. Give your grandmother a crowbar and a fulcrum and she'll make more torque than a supercharged V8. But she won't get a Corvette from rest to 60 in 4 seconds...
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unthrottled
You are clearly a bar room expert with no knowledge of how engines work. Saying "torque is nothing" is the most stupid comment I have seen in ages, how is it nothing when torque is what an engine produces.
Read some books and learn about the subject before posting anymore nonsense.
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Torque is nothing - because it's usable nature is dependent on the gearing used - power is everything because it doesn't depend on the gearing.
A good performance engine has lots of power in the USABLE engine range.
If you think torque is everything we'd all be driving electrics - where the torque is infinitely high at zero revs but drops off to virtually nothing at high rpm.
Edited by RT on 06/01/2012 at 12:07
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If you think torque is everything we'd all be driving electrics - where the torque is infinitely high at zero revs but drops off to virtually nothing at high rpm.
or even steam driven vehicles!
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Will say it once more for those who cannot or will not understand. Be it an internal combustion engine or if you want to be pedantic an electric motor or a steam engine all engines produce torque which to over simplify things is their ability to turn the flywheel, thats where torque is normally measured. For the pedantic I know electric motors don't have flywheels but lets no go there. The torque they generate is converted by cunning formula to horse power, brake horse power, kilowatts, PS ( cannot spell in German, sorry) etc which is what the public understands. Sure there must be something on Wiki but cannot be bothered.
I will now get my coat and leave.
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We all know what torque is! You seem to be the only one who cannot understand how this translates into vehicular motion. Your preferred choice of units is entirely incidental.
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Pferdestarke is the word you're looking for - it has no place outside Germany as it's a German domestic Standard, ie Deutsches Institut fur Normung (DIN) which is simply the equivalent of the British Standards Institute (BSI) - none of which should be used these days as virtually all developed countries are signed up to the Système international d'unités (SI)
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The "Horsepower sells cars, torque wins races" mantra hails from the drag strip where it has long been noted that the 1/4 mile Elapsed Time is heavily dependant on the first 60 feet. Since most American muscle cars were automatic and had a very tall first gear, the 60 foot time (and hence the outcome of the race) was dependant on having enough low end torque to get a good start.
A high horsepower engine with little low end torque would cross the line with a higher trap speed but lose the race.
In circuit racing, this advantage is lost and engines are usually tuned for maximum power with scant regard for torque. You can see this in Nascar and Formula 1 engines which have very little low/midrange torque but a massive amount of power.
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The link is the best I can find and is pretty good. Read and enjoy.
www.epi-eng.com/piston_engine_technology/power_and...m
Point 3 is exactly what I have been saying but the rest of the article needs reading.
- POWER is CALCULATED from torque and RPM, by the following equation:
HP = Torque x RPM ÷ 5252
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Calculation using mathematics is the basis of virtually all science.
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The only reason you need the torque number is to get an idea of the power at a certain RPM.
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Pferdestarke is the word you're looking for - it has no place outside Germany as it's a German domestic Standard, ie Deutsches Institut fur Normung (DIN) which is simply the equivalent of the British Standards Institute (BSI) - none of which should be used these days as virtually all developed countries are signed up to the Système international d'unités (SI)
Pferdestärke literally translates to 'horse-strength' 'Pferde' is 'horse' and 'stärke' means 'strength/strong'. Horsepower.
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