Fuel Consumption Diagram

[andru123]

Is there a fuel consumtion digram for yaris engine(s)? (Or graph, or chart or table)

I noticed that it consumes differently at different speed, but I cant figure out the optimal... :(

[Chappers]

It's not really speeds, more gearing and revs..

[s0cks]

but... if you travel 100 miles at 70mph will you use less fuel then travelling 100miles at 50mph? Because at 70 you'll get there quicker then at 50. But 50 should be more optimal :) Confusing!

[Chappers]

but... if you travel 100 miles at 70mph will you use less fuel then travelling 100miles at 50mph? Because at 70 you'll get there quicker then at 50. But 50 should be more optimal :) Confusing!

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Fuel consumption.. Time is relative to speed, as one increases, the other decreases and so forth...

You will travel further @50mph than @70mph

So no, you will use more fuel, just get there quicker!

[kanarnthan]

as a vague rule in most cars the optimal efficiency is driving in 5th at lowest constant speed possible without stalling!!! :P So in my 1.0l if i did 22ish mph constantly in 5th fuel consumption would be something ridiculous like 70mpg!!! :D

[Crisis]

Kind of true. But you may start to choke the engine in too high a gear meaning you use more fuel.

[s0cks]

You only really start choking the engine when it begins to cough and splutter (like accidently pulling away in 3rd thinking your in 1st!). As long at the car is moving steadily it should be alright. Doing 30 in 5th on the TS is perfectly acceptable :)

[dicey2k]

Constant 58mph in top gear is supposed to be the most efficient speed in any petrol vehicle... allegedly!

[Blue84]

Constant 58mph in top gear is supposed to be the most efficient speed in any petrol vehicle... allegedly!

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I thought it was 56 mph :P

[alanbradley]

No, the reason you get stuck at 56mph is that that's 90kph and that's the speed the limiter should be set at on an HGV

I thought it was all to do with the peak torque of your engine?

A

[Demonic Angel]

as a vague rule in most cars the optimal efficiency is driving in 5th at lowest constant speed possible without stalling!!! :P  So in my 1.0l if i did 22ish mph constantly in 5th fuel consumption would be something ridiculous like 70mpg!!! :D

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Sure though if the engine is struggling in 5th then its using more fuel?

I've gone 30 in 5th before - by accident! It was fine though - only realised I was in 5th when I went to change down a gear!

[jonbro2000]

No, the reason you get stuck at 56mph is that that's 90kph and that's the speed the limiter should be set at on an HGV

I thought it was all to do with the peak torque of your engine?

A

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I agree Alan, you have to see what revs your peak torque is, calculate that speed and that is the most efficient running of the engine.. therefore it uses less fuel. However, making a car labour uphill in top gear even at peak torque actually uses more fuel than dropping down a cog... something to do with resistance squares with speed I think

[Bibbs]

The reason 56 and 72 are used is cause of what they are in kmph .. they are NOT the most efficient, just the most quoted.

In any car the most fuel is used getting over the drag of the car through the air, lower the speed the less drag.

So the lowest revs, in the highest gear = lowest speed ..

[RaineesLover]

I have found by trial and error that the best consumption is at 3500 revs in 5th gear which gives a constant 65mpg (something I achieved during the fuel shortages).

Having done 130,000 miles in my Yaris since I bought it in April 1999 I have had plenty of practice :)

[alanbradley]

Wahey! A new mileage champ! :hokus-pokus:

Damn, that's getting on for double the Yarii miles I've done in total :(

Hi and welcome to the club btw..

A

[RaineesLover]

Wahey! A new mileage champ! :hokus-pokus:

Damn, that's getting on for double the Yarii miles I've done in total :(

Hi and welcome to the club btw..

A

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Thanks Alan from another Alan!

[dicey2k]

Constant 58mph in top gear is supposed to be the most efficient speed in any petrol vehicle... allegedly!

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I thought it was 56 mph :P

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Thanks T, my bad!

RaineesLover - Did they actually make a 1.0 CDX? Thought it was just a 1.3 model?