[amitoj]

Originally Posted by Sawyer

I will look that up - actually I am surprised to hear that, I have an i 20 with the same engine in it, and the only time I keep tabs on the FE is on highway runs, when I have consistently got 17/18 kms a litre. I would think that the i 10 would at least equal that, is the Suzuki very much better?
Anyone who knows the ARAI measured numbers for the two engines, please post them.

On an average, the K series is better by 1.5 to 2 kmpl. Of course, i am not considering the 1.2 AT version here. AT is a whole different story.

After kerb weight, next important aspect to consider when comparing FE is the tyre spec.

EDIT: Courtesy Sidindica:
http://www.team-bhp.com/forum/test-d...ml#post1421783

Seems i10 ARAI is "about" 16.8 kmpl and K series is 17.7 kmpl

[Sawyer]

Originally Posted by amitoj

On an average, the K series is better by 1.5 to 2 kmpl.

I am curious to see if that shows up in the ARAI numbers as well, we will get to see when someone posts the Hyundai ones for the 1.2 petrol. Preferably for both the i10 and 20.

[amitoj]

Originally Posted by Sawyer

I am curious to see if that shows up in the ARAI numbers as well, we will get to see when someone posts the Hyundai ones for the 1.2 petrol. Preferably for both the i10 and 20.

See my edited post below. The exact ARAI figures are not available ( wonder if a manufacturer should be allowed to conceal these numbers) .
I also checked out their website
Home : Automotive Research Association of India(ARAI)

Everything there is "Under Construction"

[GTO]

ARAI figures are not supposed to be indicative of what your car will deliver in a daily urban cycle. ARAI themselves know that (test includes driving at a constant speed). Where ARAI numbers come in handy is relativity.

In their tests the FE of the Swift > Ritz > Indica. Thus, if you were driving a Ritz in Pune at managing 12 kpl (in YOUR driving conditions), you can bet that the Swift would be marginally more fuel efficient, and the Indica less so.

Again, use ARAI only from the relativity POV.

And yes, engines of the exact same size can have varying FE numbers. Case in point : My ex-Lancer and ex-OHC Vtec. The Honda had 20% more power, yet was more fuel efficient (in the city and on the highway).

[Mpower]

Originally Posted by Sawyer

What I am trying to get at is that if I am looking at two cars, and once both have the same engine capacity and same fuel driven engine, can I assume that there will, at the end of the day, and in real life, be no significant difference in the actually returned FE.

They are not the same but 90% are all within 1-2 kpl of each other. Exceptions....Honda usually tops the list and Fiat usually is in last place. Suzuki is above average Hyundai is average and Euro petrols are below.

Weight is a big, big factor and then there is just engine efficiency and gearing.

Aero is not so important for city and low speed highway plus they are all around the same Cd.

[Amartya]

Originally Posted by Mpower

They are not the same but 90% are all within 1-2 kpl of each other. Exceptions....Honda usually tops the list and Fiat usually is in last place. Suzuki is above average Hyundai is average and Euro petrols are below.

Weight is a big, big factor and then there is just engine efficiency and gearing.

Aero is not so important for city and low speed highway plus they are all around the same Cd.

Perfect.

Just wanted to re-emphasize:
Your second point about the weight also answers (to a certain extent) why Honda and other Japs are usually at the top, and Fiat and other Euro hatches near the bottom of the pile.

[Sawyer]

I have found some Hondas to not be quite so efficient, and I am guessing it is the larger engines such as in the CRV and Civic.
On the ARAI point then, is it ok to assume that the difference in the numbers will translate reasonably accurately into real life driving of the respective cars as well? If so, then the ARAI information is very useful to keep in mind while evaluating two cars. And that pretty well concludes the need for further discussion on this subject.

[aaggoswami]

1) IIRC, we have another thread related to this topic or almost identical topic.

2) The rating by ARAI are misleading. What the rating for ? To tell the customer of FE. The FE customer will get depends on where he drives, how he drives, condition of car, tyre pressure, etc. Obviously the FE would vary from person to person, location to location.

These ratings are of no practical use IMHO. I have seen people with FE of 14-15 in city driving in Alto and FE of 12-13 from SX4 in city.
Rather than offering these figures, there must some other norm like that of emission.

Real world testing again cannot give perfect figures or near to perfect figures as the traffic, driver, etc would vary.

3) No two engines from different brands will be similar. Lets compare 1.2 from Fiat, 1.2 from Suzuki and 1.2 from Honda. Honda has best top end, but weak bottom end, Suzuki has nice spread of power with good top end, Fiat is pretty weak as compared to Honda and Suzuki.


IMHO, this is flawed system to measure FE, not really helping the customer out. What he gets depends a lot on customer driving style and traffic conditions. Its better if we get some data regarding emissions rather than FE.

[longhorn]

If the ARAI follows a standard practice for all models, then we can know which vehicle give better FE relative to another. Of course the FE we get can vary, but assuming that the ARAI follows a standrad set of procedures for this measurement, we can know the FE of one vehicle compared to another. Other things being equal, if one were to drive X brand vehicle and Y brand in similar situations, the vehicle having better ARAI figures should give better FE than the other.

[pratim]

Originally Posted by aaggoswami

1)
IIRC, we have another thread related to this topic or almost identical topic.

2) The rating by ARAI are misleading. What the rating for ? To tell the customer of FE. The FE customer will get depends on where he drives, how he drives, condition of car, tyre pressure, etc. Obviously the FE would vary from person to person, location to location.

These ratings are of no practical use IMHO. I have seen people with FE of 14-15 in city driving in Alto and FE of 12-13 from SX4 in city.
Rather than offering these figures, there must some other norm like that of emission.

I tend to disagree here; we all know that these are reference values and obtained under certain test conditions like tarmac, driving style, speed etc. Actual FE for different users vary depending so many different factors (as posted by so many folks in this thread), so that it is very difficult to standardize anything. So, if ARAI has to come up with some figures, they have done the right thing by standardizing test conditions. We should commend their efforts. As GTO said, ARAI figures can be used in relative terms, as a means of comparision and not be taken as absolute value.

@longhorn, +1 to your view.

Cheers
Pratim

[Technocrat]

Originally Posted by aaggoswami

1)

2) The rating by ARAI are misleading. What the rating for ? To tell the customer of FE. The FE customer will get depends on where he drives, how he drives, condition of car, tyre pressure, etc. Obviously the FE would vary from person to person, location to location.

These ratings are of no practical use IMHO. I have seen people with FE of 14-15 in city driving in Alto and FE of 12-13 from SX4 in city.
Rather than offering these figures, there must some other norm like that of emission.

No its not misleading, See if a car A's advised mileage is X & that of car B is X-2 & a customer is getting mileage as Y for car A he can be sure that under his driving conditions car B will be giving a mileage around Y-2. So it helps in putting things into perspective.