[sadsack]

Originally Posted by hybridpetrol

There is quite a fan base for Nano - those who already own a Nano, would want to drive a better Nano actually, not anything else.

Reasons?
a) The interior space offered by Nano is unmatched in the segment. All four occupants can be seated in comfort, and ingress & egress is super easy.
b) Joy to ride in the city. Same with parking.
c) Cute looks!
d) Comes within the pocket. Comes with all the convenience features that is usually offered on top variant in A segment, but at the price less than the base version of Alto 800.

This observation is quite correct. I have owned the Nano and sold it off because I wanted to buy an automatic transmission car for my wife. I am a huge fan of the Nano and I now believe that I made a huge mistake in selling that car off. The Nano did not need anything more, not even the hinged tailgate. All people who drove the Nano agreed it was a fun car in the city.

Ratan Tata was right in wanting to make the Nano. He was wrong in choosing West Bengal as the location for its factory. It is a story of, if only..... I don't know what this Pelican thing is. Tata has been trying all kinds of stunts to make the Nano more desireable and all that those stunts succeeded in is providing fodder to those who had a low opinion of the Nano (a very high percentage of the naysayers never sat in a Nano, leave alone drive one). The attempts at repositioning it somehow reinforced the idea that there was something wrong with the original car. Without any exercise at positioning it, it emerged as an inexpensive to own and more inexpensive car to maintain. It must be remembered not all people are put off by the tag of inexpensive or cheap. That happens only in some parts of the country and it is not politically correct to name those parts of the country or the communities that inhabit them. Most certainly this forum is not representative of the diversity of thought and opinions in India.

The Nano should have just been advertised as a car with its price printed. No positioning was required. It was the only car of its kind. Now the Nano is slowly getting closer to the Tiago in terms of pricing. Someone at Tata Motors is unable to see the the Indian car market properly. The bombing of the Bolt, and probably of the Zest as well, and now the Tiago (what kind of a name is that is what people ask me and most of them do not know Lionel Messi so they are not aware of his son's name) are all dragging Tata Motors down. Tata motors is slow in producing new car platforms and unimaginative in the making of cars that stand out from the others and adding to the woes of the company, the journalists who write reviews always say "for a Tata the car's refinement levels are great" and just because they are journalists it does not mean that they have an expertise in anything. And the internet, social network journalists like you and me usually end up imitating the real ones, thus making it more difficult for companies to establish their products properly (in fact, I have noticed a tendency among journalists to praise something that is doing well to high heavens and trash those that are not doing well, which only goes to prove that nothing succeeds like success).

Tata needs to think hard and quick and come out with out of the box solutions like the Indica which had the good fortune of finding success and the second, the Nano which had the misfortune of failure due to no fault of its own. Tata is probably getting ready to the road taken by Hindustan Motors, Premier Automobiles and Standard Automotive Products. The last pure Indian car maker is on a ventilator, that is for sure. Will it breathe on its own again. I sure hope it does.

[Sutripta]

Originally Posted by Viju

AFAIK, only the base variant of the first generation Nano came without a brake booster. All the other variants and later models came with a 6" booster. At the time of launch, it was the smallest brake booster fitted to any passenger car in India.

My headscratching had to do with the 'why' rather than the 'what'. As in why does a light low powered car with drum brakes, and built to a (very aggressive) cost need a brake booster.

Regards
Sutripta

[silverado]

Originally Posted by Sutripta

My headscratching had to do with the 'why' rather than the 'what'. As in why does a light low powered car with drum brakes, and built to a (very aggressive) cost need a brake booster.

Regards
Sutripta

Is your WHY for light weight or is it for Cost?

If its cost, then they have clearly differentiated that cost factor by not giving it in lower variant.
I am not sure if you have driven a Nano at speeds. I have used my Nano on highways a lot.
Even in city, Nano being a peppy car reaches 60 quite easily, so any additional boost in braking is needed once its loaded with 4 adults.

My earlier ride was a Padmini, and i could feel the difference that booster bought to braking in nano.
Again not comparing braking abilities , but just the feel that booster gives you when you brake and also the additional bite.

I assume TATA must have given powerful brakes considering it could also be overloaded like its trucks

[Sutripta]

Lightweight, low powered, drums => booster should not be necessary.
Add (unnecessary) booster => Increase in cost.

Marutui van had drums.
Van, M800, Gypsy initially did not have boosters.

Regards
Sutripta

[shashanka]

[quote=sadsack;3998975]

Originally Posted by hybridpetrol

There is quite a fan base for Nano - those who already own a Nano, would want to drive a better Nano actually, not anything else.

Reasons?
a) The interior space offered by Nano is unmatched in the segment. All four occupants can be seated in comfort, and ingress & egress is super easy.
b) Joy to ride in the city. Same with parking.
c) Cute looks!
d) Comes within the pocket. Comes with all the convenience features that is usually offered on top variant in A segment, but at the price less than the base version of Alto 800.]

This observation is quite correct. I have owned the Nano and sold .................. hope it does.

Excellent post - well thought out, to the point and most importantly, gives an owner's perspective - an aware and well-grounded owner. I have not owned a Nano (I already had the transport I needed) but openly rooted for the couple of acquaintances who bought one and would spend time chatting with them about their car. "......will it breathe on its own again. I sure hope it does". Amen to that.

[1100D]

Originally Posted by Sutripta

Lightweight, low powered, drums => booster should not be necessary.
Add (unnecessary) booster => Increase in cost.

Marutui van had drums.
Van, M800, Gypsy initially did not have boosters.

Regards
Sutripta

Simply for lightening up the pedal on customer feedback (one specific section of customers) nothing else.

I am sure the Benchmark were the irritatingly superlight pedals on cars from Hyundai.

Originally Posted by silverado

My earlier ride was a Padmini, and i could feel the difference that booster bought to braking in nano.
Again not comparing braking abilities , but just the feel that booster gives you when you brake and also the additional bite.

Premier Padmini/Fiat 1100D (Although they had drum brakes) were prety adept in the braking department as long as you had things maintained properly. (Someone said, overbraked by design)

The Brake feel of a Booster assisted vehicle is lighter than that of a non-assisted one (especially on vehicles like these) and gives a feel of higher bite, though on a non-assisted vehicle, the pedal travel (against pressure and additional effort) will give you the required bite anyway.

Have driven a non-booster early Nano, did not feel that the vehicle required Boosters, even though the vehicle did reach decent speeds inside the city. Infact the Booster version feels too grabby in comparison.

[silverado]

Originally Posted by Sutripta

Lightweight, low powered, drums => booster should not be necessary.
Add (unnecessary) booster => Increase in cost.

Marutui van had drums.
Van, M800, Gypsy initially did not have boosters.

Regards
Sutripta

i agree to an extent with you, but no entirely.

Earlier times had less stop and go traffic compared to now, could be one of the reason behind it.
I remember i had to step hard on brakes of my Padmini, so a booster surely helps in reducing fatigue and that's a cheap welcome solution.

Not only me, but many people would have paid more if we had an option of disc brakes in Nano.
I am afraid we may go off-topic here, lets just hope Pelican comes with Disc brakes.

Cheers
Ashish

[Sutripta]

My question remains: Why a booster in a setup like the Nano's.

In the Nano (and similar setups), a booster will change the 'feel', not actual braking performance.

Originally Posted by silverado

i agree to an extent with you, but no entirely.

Can't make out what you are agreeing with, and what you are disagreeing with!

Not only me, but many people would have paid more if we had an option of disc brakes in Nano.
I am afraid we may go off-topic here, lets just hope Pelican comes with Disc brakes.

Certainly offtopic for this thread.
But if someone can explain to me what exact gains one would have from disc brakes on the Nano. (Not wiki articles/ homilies on disc brakes pls.)
(Very very OT: similar clamour for rear disks on the Fortuner!)

Regards
Sutripta

[aravind.anand]

Originally Posted by Sutripta

In the Nano (and similar setups), a booster will change the 'feel', not actual braking performance.


Certainly offtopic for this thread.
But if someone can explain to me what exact gains one would have from disc brakes on the Nano. (Not wiki articles/ homilies on disc brakes pls.)
(Very very OT: similar clamour for rear disks on the Fortuner!)

Regards
Sutripta

Booster will certainly improve whatever braking power is already on offer - hence the name 'booster'. Having driven the 800 and Alto, I know the huge difference booster can bring in.

Disc brakes do not fade under repeated braking, hence are in general better. For a city specific car like Nano, it is not definitely essential - but yes, does make the Nano better equipped to face emergency situations with more confidence.

[Sutripta]

Originally Posted by aravind.anand

Booster will certainly improve whatever braking power is already on offer - hence the name 'booster'.

If by "braking power", one means something quantitative like distance to stop, then in a setup like the Nano, the booster will not make any difference.

Disc brakes do not fade under repeated braking, hence are in general better.

Oh, they do fade. But certainly far less than drums.
Nano owners have been complaining of brake fade?

Regards
Sutripta

[Viju]

Originally Posted by Sutripta

My headscratching had to do with the 'why' rather than the 'what'. As in why does a light low powered car with drum brakes, and built to a (very aggressive) cost need a brake booster.

I did not work on the Nano project myself, so these are just my assumptions as an R&D engineer who worked on brake system development for a competitor.

My targets:
① Cost: 1 lakh retail price for base variant (broken down system-wise, component-wise) - xx Rs. for brake system - xx / y for each component.
② Performance:
(a) Meet homologation requirements.
(b) Meet / exceed benchmark vehicle performance - In this case, I believe Maruti 800. The 800 came with front disc brakes, but no booster (in domestic market).
③ Packaging and weight: Meet fuel efficiency target, ease of assembly during manufacturing.

What is the least expensive solution I have?
(a) Drum brakes all around. Minimum acceptable size. Disc brakes are too costly.
(b) Eliminate brake booster (if possible to meet homologation requirements)
OR use the smallest possible booster to pass homologation. Smallest booster used by competitors at that time was 8", in the Alto.

Do I meet / exceed the benchmark vehicle performance?
(a) Stopping distance
(b) Pedal travel v/s brake output
(c) Pedal effort
(d) Pedal feel (subjective)

I do packaging and theoretical study for both 'with' and 'without booster' scenarios, and think that 'no booster' solution should work. The booster I have is 6", much smaller than what is the smallest one in the market.

Actual vehicle test results show that:
(a) Homologation results - 'OK' without booster
(b), (c), (d) - Some or all 'Not OK' without booster

I still have to meet my strict cost target for base variant. Hence I propose base variant without booster, and higher variants with a 'mild' booster - especially considering the vehicle is targeted for first-time drivers, ladies etc who may find it difficult to apply the pedal each time without any assist, especially in city traffic conditions.

This is probably what happened. I may be wrong, and since I don't know better, cannot put across any more useful points for a debate!

[im_srini]

Originally Posted by Viju

I did not work on the Nano project myself, so these are just my assumptions as an R&D engineer who worked on brake system development for a competitor.

Hello Viju, maybe , but would having the engine at the rear & having to pipe the manifold vacuum all the way to the front of the car, where the master cylinder is situated, have played any part in the decision at all ?

[sun_king]

Originally Posted by Sutripta

<snip>
Certainly offtopic for this thread.
But if someone can explain to me what exact gains one would have from disc brakes on the Nano. (Not wiki articles/ homilies on disc brakes pls.)
(Very very OT: similar clamour for rear disks on the Fortuner!)

Regards
Sutripta

Maybe a few centimeters in braking distance, probably not noticeable. The Nano is the only rear engine car of that size, so not sure what practical benefits discs would bring in. But it is also the only one around with four drums these days and that brings in some familiarization issues.

When I use my wife's Nano, it takes a few brakings to realize that the dynamics vary. Being used to the discs in my car there is an initial panic, the wooden feeling and the variation in the bite gives a few extra beats per minute for the heart. A few brakings later reality sets in and then I become the Nano driver. This instincts and muscle memory of the 21st century Homo Sapiens seems to be set for discs! If the Nano gets a pair of discs then all the world is on same wheeling.

Otherwise, the Nano is quite competent in the braking capabilities.

[shashanka]

Originally Posted by im_srini

Hello Viju, maybe , but would having the engine at the rear & having to pipe the manifold vacuum all the way to the front of the car, where the master cylinder is situated, have played any part in the decision at all ?

This would seem to be a minor issue - why not shift the master cylinder/Booster to the aft in the engine bay & let the hydraulics do all the pr. transmission to wherever needed. After all how much space would it take up, if they are already plonking in a larger engine.

Originally Posted by sun_king

Maybe a few centimeters in braking distance, probably not noticeable. The Nano is the only rear engine car of that size, so not sure what practical benefits discs would bring in. But it is also the only one around with four drums these days and that brings in some familiarization issues.
When I use my wife's Nano, it takes a few brakings to realize that the dynamics vary. Being used to the discs in my car there is an initial panic, the wooden feeling and the variation in the bite gives a few extra beats per minute for the heart. A few brakings later reality sets in and then I become the Nano driver. This instincts and muscle memory of the 21st century Homo Sapiens seems to be set for discs! If the Nano gets a pair of discs then all the world is on same wheeling.
Otherwise, the Nano is quite competent in the braking capabilities.

That, sun-king, is the neatest & most concise bit of summing-up of the issue I've come across so far! In today's world perception is all - and if familiarisation time is long enough to result in a shunt at a cross-roads (as can happen if your drive-way falls onto/near an intersection), then the arguments in favour of disc brakes wins the day!

[im_srini]

Originally Posted by shashanka

This would seem to be a minor issue - why not shift the master cylinder/Booster to the aft in the engine bay & let the hydraulics do all the pr. transmission to wherever needed.
After all how much space would it take up, if they are already plonking in a larger engine.

Yes, space wouldn't be an issue, however the cost would be.

Looking at Viju's walk-through of the thought process...

Originally Posted by Viju

These are just my assumptions as an R&D engineer who worked on brake system development for a competitor.
My targets:
① Cost: 1 lakh retail price for base variant (broken down system-wise, component-wise) - xx Rs. for brake system - xx / y for each component.
...

The cost of each component is factored in at the design & engineering phases itself.
If we go by the solution outlined, you'd need to have :
A) A cylinder at the front which is actuated by the brake pedal
B) A pipe to carry this fluid pressure to the actual master cylinder ( & booster ) at the rear of the car
C) From that master cylinder, four pipes leading to the 4 brake cylinders in the car

The solution appears a tad too complicated considering the simplistic nature of the car.
In addition, there is the added failure mode due to the extra hydraulic connection.
I'm not an automotive engineer, but it appears to me that it would be simpler to use a metal tube to carry the manifold vacuum from the engine-bay at the rear to the firewall at the front where the master-cylinder is situated in a conventional fashion.
To keep costs low, one might even use the master-cylinder from the M-800 - in contrast to designing & using a unique part ( master-cylinder actuated by hydraulic pressure ) just for the Nano.
.