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Old 29th May 2011, 21:30   #16
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Default Re: Some numbers in brochures don't make sense...

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Originally Posted by GTO View Post
Nice thread. As Vishal posted, numbers alone make little sense. Example:
- Kerb weight : Not necessary that the heavier the car, the safer it is (or even feels more solid).

- Wheelbase : The Linea is a prime example here. While the wheelbase ain't too bad, it's the most cramped from the segment. Poor interior packaging, really.

- .
kerb weight - Yes the old Sumo was one such gaadi. Very heavy, Short wheelbase (indica has the same wheelbase) and not at all safe.

Length - Punto is longer than most of the cars in its segment but the rear is not as spacious as it should be. Same with Polo. Whereas the Honda Jazz. you know it clever packaging.
Alto K10 is longer that Alto but there is no space increase... the whole length increase is in the engine compartment.
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Old 30th May 2011, 11:41   #17
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Default Re: Some numbers in brochures don't make sense...

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Originally Posted by rjstyles69 View Post
Completely agree with what Rehaan say's, mostly has to do with the softness of the suspension. From what I know manufacturers display GC numbers for an empty car, no passengers or cargo. Beyond this if a car is fully loaded then yeah talk about softer suspension setups which is the main cause for the underbelly scrapping.
According to my experience, Vista has a much softer suspension and this makes it more rocky and a pain to handle on curves at speeds. Figo on the other hand has a harder suspension to make it a better handler. And the wheelbase of both cars differ by 19 mm (Figo: 2489, Vista: 2470). Would a 19 mm increase in wheelbase not only negate a 3 mm increase in GC but make it much less in real? Also, a layman's point of view.. When i get into my car (Vista), its more like walking in (am 5.5) and with Figo, i have to bend a little. Is it always the maximum GC numbers that we see?

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Originally Posted by Rehaan View Post
This is another good example!

BHP and in most cases torque are always mentioned at their peak value only.

However, two cars having the exact same power @ exact same RPM might have completely different power characteristics at a lower RPM. This would depend on several factors, engine displacement, # of valves, cam profiles, forced induction vs NA, etc.

The only way to compare on paper is to look at the full power curve, which manufacturers rarely provide.

Even if the power curves match exactly on paper, don't forget that power-to-weight ratio, as well as gearing can still make a difference to how powerful a car feels!


Lately, especially with the diesels, a lot of manufacturers have started mentioning peak torque across a band (eg. 500Nm @ 1700 - 2600 RPM). This also helps in showing the car's drivability across that rev range.

cya
R
Not to forget the height, wheelbase, design aspects.. I have had problems with handling and control with my Vista because of cross winds at high speeds and not so appreciated aerodynamics. Also, will panel gaps (my bumper was removed once to change horn and didn't get back to its original place making the panel gaps wider) effect high speed performance?

Quote:
Originally Posted by GTO View Post
Nice thread. As Vishal posted, numbers alone make little sense. Example:

- The Civic's torque curve on paper isn't really that bad. However, thanks to the poor throttle response, I have yet to drive a car that's as bad to drive in traffic as the Civic. I'm just glad I got the exhaust changed and improved my low-end torque delivery. It was a ROYAL pain in stock form.

- They say Korean horses are generally weaker than Japanese / European ones. This is much the case with the petrol Accent, as an example. It simply isn't as fast as the power to weight ratio would suggest. Another example is the Punto 90 BHP. Hardly a difference from the 75 BHP variant.

- Kerb weight : Not necessary that the heavier the car, the safer it is (or even feels more solid).

- Wheelbase : The Linea is a prime example here. While the wheelbase ain't too bad, it's the most cramped from the segment. Poor interior packaging, really.

- Boot capacity : Larger doesn't necessarily mean better. The layout, and usable space, are equally important.

I think punto was a little underpowered with 75 bhp than the other cars wich share the same heart (swift, ritz, palio and vista) owing to its weight. I thought with 90 bhp engine (VGT i suppose?) it would be a little better.

Boot capacity: I completely agree with you GTO, the layout and the wheel well intrusions matter too. With hatchbacks its always a bargain with how much leg room your get. Vista is the longest along with Figo when compared to Ritz and Siwft, but has much lesser boot space than all of them.

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Originally Posted by oxyzen View Post
The most baseless number is KMPL. You may end up getting more FE in a car that claims less FE.

- These days engine calibration is done in such a way that ARAI certified fuel effeciency is maximum. The first thing they do is kill the throttle response. The next thing is to provide a taller 2nd & 3rd gear. Then they make the cars forcibly wear skinny tyres. And finally measure the FE with AC off.

- Now when it comes to real life driving, you see the car is just not performing. You give it more gas. You drive it in a gear less.
Moreover some of us obviously upsize their tyres. And practically everyone drives the car with AC on.

So does the Arai certified FE hold any value?
Are ARAI figures derived from road tests or are they from lab tests under standard conditions? I was once surprised by Yamaha Libero's fuel efficiency figures, users claimed around 125 kmpl or so. Was wondering if they used to switch off their engines on descent

Quote:
Originally Posted by figo_mba View Post
kerb weight - Yes the old Sumo was one such gaadi. Very heavy, Short wheelbase (indica has the same wheelbase) and not at all safe.

Length - Punto is longer than most of the cars in its segment but the rear is not as spacious as it should be. Same with Polo. Whereas the Honda Jazz. you know it clever packaging.
Alto K10 is longer that Alto but there is no space increase... the whole length increase is in the engine compartment.
Increase in wheelbase is definitely good for the handling, but does not necessarily always mean an increase in interior space. Height and width of a car also matters. Ritz has much better space in the front, i felt a little cramped in punto for my height itself.

Last edited by gurudutt : 30th May 2011 at 11:44.
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Old 30th May 2011, 11:57   #18
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Default Re: Some numbers in brochures don't make sense...

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Originally Posted by gurudutt View Post


Not to forget the height, wheelbase, design aspects.. I have had problems with handling and control with my Vista because of cross winds at high speeds and not so appreciated aerodynamics.
We had a petrol indica vista which has this issues with aerodynamics. Strong Crosswinds across open fields (road in the middle and field on both sides for long distances) used to un settle the car. I do not know if your mis aligned bumper is adding to it.

Quote:
Originally Posted by gurudutt View Post

I think punto was a little underpowered with 75 bhp than the other cars wich share the same heart (swift, ritz, palio and vista) owing to its weight. I thought with 90 bhp engine (VGT i suppose?) it would be a little better.
I feel it is not just the weight of the punto but also the gearing. My friend who owns a punto says he feels funny using the first and second gear because there is no surge at all. He says it is the third gear that is actually usable. Indica which weigh as much as a punto is quicker from rest but yeah aerodynamics hits indica hard later. Point is 90bhp has not made punto noticeably quicker.

Quote:
Originally Posted by gurudutt View Post
Increase in wheelbase is definitely good for the handling, but does not necessarily always mean an increase in interior space. Height and width of a car also matters. Ritz has much better space in the front, i felt a little cramped in punto for my height itself.
Wait till you have tried linea then. I cannot sit in the rear seats because at 6'1" my head hots the roof and if i were slide down into the seat my knees would hit the front seat (my dad and bro are also as tall as I am adding to the trouble) Figo which is much smaller (length and width wise)we feel gives much more space. And honda Jazz is the killer in this. Smart liberation of space. Eveybody learn from the Jazz
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Old 30th May 2011, 12:02   #19
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Default Re: Some numbers in brochures don't make sense...

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Originally Posted by GTO View Post
- Kerb weight : Not necessary that the heavier the car, the safer it is (or even feels more solid).
Wasn't there some excise rule once upon a time which dictated tax on UV based on kerb ( or is it curb as per USA) weight ? I remember reading once in context of Mahindra Armada later the emphasis was on CC capacity and length of vehicle to define what is small car.

I have heard similar rules in other countries are responsible for useless figure such as kerb weight being mentioned up front.
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Old 30th May 2011, 12:32   #20
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Default Re: Some numbers in brochures don't make sense...

And its strange, surprising and funny when the word "Best/Maximum" gets comfortably replaced with "Optimum" when your numbers are less than that of a competitors when you attempt to prove your machine is better .

Check the image attached, as a matter of fact, Ritz handles better than Vista even though its taller.
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