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Old 24th November 2010, 10:57   #16
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Quote:
Originally Posted by praful View Post
@GTO: Can we be sure that Fiat has reduced just the sheet metal thickness? It could also be possible that some of the weight loss has happened due to other parts within the engine and transmission as well?

Can someone try mailing Fiat to get this info accurately!
Wouldn't it be a good idea for your friend to just take a TD of the car and arrive at a decision? Would the kerb weight of the car really matter so much to him? Surely, it should not be a deal breaker.

Website info could sometimes be incorrect. I remember Honda's site jacking up the GC of Civic from 155 mm to 170 mm when the Altis was launched.
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Old 24th November 2010, 11:55   #17
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HSS or high strength steel is the grade of sheet metal used in the modern cars from quite sometime now.

If this is the real thing which has resulted in the weight loss program in the fiat cars without compromising any structural strength of the shell, then it is indeed a break through in the metallurgical sciences..
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Old 24th November 2010, 12:32   #18
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2009 punto brochure
Punto loses some weight, It's now lighter.-untitled1.jpg

2010 punto 90 HP BS4 diesel brochure
Name:  untitled2.jpg
Views: 1957
Size:  137.0 KB

2010 punto BS4 76 HP diesel brochure
Punto loses some weight, It's now lighter.-untitled12.jpg

Weight reduction of 60 KGs shown.
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Old 24th November 2010, 12:38   #19
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Quote:
Originally Posted by praful View Post
@GTO: Can we be sure that Fiat has reduced just the sheet metal thickness? It could also be possible that some of the weight loss has happened due to other parts within the engine and transmission as well?
Bingo. That's exactly what my friend figured out. In the new specs of the Fiat, they have also apparently removed the mention of 'Rear Stabilizer Bar' implying that it is now not part of the new cars.

Quote:
Originally Posted by fuel_addict View Post
Wouldn't it be a good idea for your friend to just take a TD of the car and arrive at a decision? Would the kerb weight of the car really matter so much to him? Surely, it should not be a deal breaker.

Website info could sometimes be incorrect. I remember Honda's site jacking up the GC of Civic from 155 mm to 170 mm when the Altis was launched.
According to him, Fiat is chosen over others, notably Japanese cars due to its perceived solid build. If weight reduction is achieved by removing the Stabilizer Bar and using thinner guage, then the balance would tilt in favour of Japanese cars due to their functioning which though hassle free, is unexciting.

BTW, since the weight issue has now been confirmed by GTO, it cannot be wrong.

Quote:
Originally Posted by tantragna View Post
HSS or high strength steel is the grade of sheet metal used in the modern cars from quite sometime now.

If this is the real thing which has resulted in the weight loss program in the fiat cars without compromising any structural strength of the shell, then it is indeed a break through in the metallurgical sciences..
I think someone needs to get to the bottom of whole issue.

Last edited by captrajesh : 24th November 2010 at 12:40.
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Old 24th November 2010, 12:41   #20
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My gut feeling is that there is not weight reduction at all. Its all just a marketing gimmick.

But I'd be happy to see if this 60Kgs weight loss is for real and it comes not from using thinner sheet metal, but from other lighter components from the engine/transmission/electricals/etc.
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Old 24th November 2010, 13:06   #21
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Another surprise: Look at the kerb weights of Linea.

BS 3 brochure

Punto loses some weight, It's now lighter.-untitled1.jpg

BS 4 brochure

Punto loses some weight, It's now lighter.-untitled12.jpg

around 80 kg reduction. I still suspect misprint.
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Old 24th November 2010, 13:21   #22
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It may not be a print error!

Read this article

DOCOL - SSAB meets the high requirements of Fiat

Why not Fiat advertise this if the Indian Fiats have started sourcing the steel from SSAB?
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Old 24th November 2010, 19:42   #23
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Yes, the punto's weight has been cut down and this was felt physocally when I inspected the car today in the showroom. The thud of the doors and the overall effort in lifting the bonnet is much less than before, more akin to a volkswagen polo, though still stronger than the polo.
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Old 24th November 2010, 23:24   #24
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Wow! That is quite a reduction in the weight. 60-90kg is a huge reduction. Hope Fiat is not compromising much in terms of exterior build quality, and strength.
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Old 25th November 2010, 14:54   #25
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As far as consumers are concerned, weight reduction should not be a mere cost cutting measure.

The main questions that need to be answered are:

1. Is the weight reduction only on account of reduction of thickness of the body panels?

2. Does that affect the stiffness of the Monocoque body?

3. Do the previous NCAP ratings hold good for new cars?

4. Why was the rear stabilizer bar removed? How would it affect the car's high speed stability?

5. Why is the weight reduction not standard across the board?
- Punto 1.4 petrol weight has been reduced by only 15 to 20 Kgs.
- Punto 1.2 has been reduced by 50 kgs and
- Punto MJD has been reduced by 60 kgs.
- Same is the case even with regard to Linea.

6. Considering that the maximum reduction happened with diesel cars which have heavier engines, has the reduction been achieved by modifying engines and/or their metallurgy?

7. Most importantly, Fiat has not tom-tomed about the weight reduction in the media but went about the whole business of weight reduction on the quiet. Had the weight reduction achieved by usage of better/lighter materials but with same stiffness, then it would surely be their USP. But going by the way the entire exercise has been carried out, it doesn't appear to be so.

Any guesses? Hope some one comes out with little inside information.

Last edited by captrajesh : 25th November 2010 at 14:55.
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Old 26th November 2010, 00:32   #26
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SSAB steel have been associated with Punto since 2006, I just checked Punto Evo brochure from UK website and I found the following

1) Weight difference between 3dr and 5dr is a mere 15kg
2) 1.2 5dr - 1030 Kgs, 1.3 75HP 5dr - 1105 kgs

My guess is that they changed the steel supplier.

I vaguely remember Dr.Sumantran from an interview on an auto magazine a lot of years ago that the Indian automotive steel industry was not able to provide them steel of a lower gauge/thickness for a certain tensile value, that was the reason why the Indica was a bit overweight at birth.

May be OT : The Etios is expected to weigh in at 930 kgs, but I dont remember seeing a single comment that the car might not be safe at all * runs for cover *

Last edited by indivic : 26th November 2010 at 00:35.
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Old 26th November 2010, 11:25   #27
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Maybe, it is a good idea to make the first and second gears slightly taller, now that the Linea and Punto have successfully completed their diet regime.
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Old 26th November 2010, 13:53   #28
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Due to the fact that car manufacturers need to lower the exhaust emission values year on year for tax reasons as well as making the products constantly cheaper, cars will heve to get lighter.

Often cars are over engineered and/or designed in rather starnge ways. This is due to too much computer simulation and too little engineeering experience.

As a result problems come up during the development process that necassitate changes. These changes are often more add ons than actual changes. These add ons in some cases require more chnges. Dependiing on how far the project is advanced determines the action taken.

Often are measures implmented that prove unnecessary.

For example when the 1.2 16v FIRE engine was introduced fitted to the Fiat Punto Mk1 it had 32 valve springs. Double valve springs allow for much higher rpm than single valve springs. It was thought that the increased rpm necessitate double valve springs for this engine configuration, but proved unnecssary. Result was the springs have been changed to single. Saved Fiat annually 8 million springs at the time.

After the launch of a model desigenrs still work on them to find ways to reduce material. Doors might have 3 or four sections of different gauge steel, which is used as the strength needed.

Stress simulation might help development, but the reality is often different. From studying the feedback from own testing reports from service station feedback etc a more complete picture is provided allowing to make changes that will save weight. A lot of the reductions have a knock on effect, which can be twofold.

For example, when doors get lighter the re-enforcement of the A- pillar as well as the b-pillar (and in 5 door applications the C-pillar) can be reduced saving weight. The reduction in strngthening plates has no adverse on the structural abilty on impact, whether from fornt or side.

Dependiing where the weight reduction takes place it might alter thebalance of the car, which means further weight can be removed to get the balance back.

Another example: The 44Ah battery in my car weighs 12.3kg. The same manufacturer also makes a battery with a different shape with 45Ah a slightly higher cranking power but at 8.7kg. Virtually the same capacity but 3.6 kg lighter.

The Fiat group had to learn a bitter leasson lately. When Alfa Romeo launched the Brera and 159, the management of the group decided that the car will be made from cheaper but much heavier materials, Alfa at the time produced not even 3,80,000 cars. A year later they went down to 1,40,000 cars. True Alfisti do not buy overweight barges.

There is many more points to it, but this would lead boringly far.
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Old 30th November 2010, 17:17   #29
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Quote:
Originally Posted by anachronix View Post
It may not be a print error!

Read this article

DOCOL - SSAB meets the high requirements of Fiat

Why not Fiat advertise this if the Indian Fiats have started sourcing the steel from SSAB?

That is a nice find, to quote from the article

Quote:
By using high strength steels, the body weight of the Grande Punto has been cut by 32 kg. When the whole product lifespan is considered, this corresponds to a fuel saving of 150 litres and up to 400 kg less of CO2 emissions.
So the 30 kg weight reduction does make sense and the stabilization bar may have been removed because of the decreased weight now!! Wow! So did anyone find the difference in performance for the lighter Puntos?
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Old 30th November 2010, 22:38   #30
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What I can make out is that most of us are speculating. It reminds me of the old story of a bunch of blind men going around groping an elephant. Does anyone have some meaty / juicy insider information?
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