[pranavt]

Originally Posted by mempheS.D

Dear pranavt,

the explanation here is neatly done and definitely needs to be understood before one takes the plunge to pay the extra few shillings just because the engine spec is "in". I agree with you that these new-gen engine technologies at par with the current age. But, what's the point if we really cannot use it to meet the intent? (It's like how the whole of India was crazy about multimedia phones in the early 2000s, but the network providers still didn't have the infrastructure to utilize thees phones to the limit!)

So you are getting more power. And you are still getting better fuel economy than a non-DI engine. And you have an engine that has been developed, keeping in mind concepts like swirl and tumble. And a more efficient combustion chamber that CAN be run a lot leaner than conventional combustion chambers when given the ability.

The engine spec is not "in." It is not fashion. It is engineering. And much better engineering than some of the trash that's released by big-name manufacturers. And it is the direction that is being taken by almot all companies around the World. From a beige Toyota to a red Ferrari.

Finally, you are not being forced to buy the car. Or pay for the technology. There are a multitude of manufacturers that can cater your needs with decade old technologies that will not need any change in your immediate environment or government regulations for their maximum efficienty. Which is still less than what is offered by stratified and direct fuel injection.

My opinion is just that. An opinion. An educated one. I do not care what you wish to do with your money. It is your own.

[mempheS.D]

Post deleted by the Team-BHP Support : Please do NOT post one-liners that add little or no informational value to the thread. We need your co-operation to maintain the overall quality of this forum.

Please read our rules before proceeding any further.

[GTO]

Here's a related thread on the matter : Link.

And my post which might be relevant:

Originally Posted by GTO

The Laura really has the best petrol engine in the segment; the Civic & Altis don't even come close. Drive these three cars back to back and you'll think that the Honda & Toyota have engines from a full class below. That's saying a lot, as the Japanese have typically excelled at petrol engines (the way Europeans do diesels).

Plus, the TSI is such an all-rounder. Great torque low down, extremely revv-happy, powerful and reasonably fuel efficient too (well, atleast as much as the Civic).

Why doesn't everyone offer it? One reason is cost. Turbo-charging would cost noticeably more, as would the development & production of direct injection. A relevant point : The Japanese simply don't innovate the way that the Europeans do. I mean, Honda & Toyota are still selling the same kinda petrol engines they used to in the nineties. Where is the step ahead? Where are the improvements?

[anandpadhye]

Originally Posted by pranavt

So you are getting more power. And you are still getting better fuel economy than a non-DI engine. And you have an engine that has been developed, keeping in mind concepts like swirl and tumble. And a more efficient combustion chamber that CAN be run a lot leaner than conventional combustion chambers when given the ability.

The engine spec is not "in." It is not fashion. It is engineering. And much better engineering than some of the trash that's released by big-name manufacturers. And it is the direction that is being taken by almot all companies around the World. From a beige Toyota to a red Ferrari.

I agree.

The latest tech should always be welcome and kudos to Skoda for bringing the TSi before anybody else. I, for one, really enjoy driving my Laura TSi and in one of the YouTube videos about the TSi, I came across the statement that the VW group is striving to make motoring more efficient at the same time not sacrificing driving pleasure. Now, I admire this attitude.

For me, one definate way to check the factuality of the claim in this thread (that TSi is useless in India ...because of our petrol quality) is to use a tankful of speed97 and see if TSi (which is already returning decent FE of around 12kmpl @160kmph, 15/16kmph @100kmph and 9/10kmpl in city traffic), becomes super efficient with speed97 or not. May be one day I will try.

As for the fun part or the driving pleasure, the Hondas and Toyotas do not even come close to the TSi...of course one may claim that it's simply because of the turbo as the Octy TPi/vRS was also huge fun to drive...but I have feeling that TSi is a bit more fuel efficient than TPi.

BTW, Laura TSi has GDI and variable valve timing and 6'th gear -definately not useless for me.... And Laura TSi costs less than the Civic which does not have turbo or GDI or 6'th gear so I did not pay more for GDI even if GDI *MAY* not be active some of the time.

Disclaimer: All cars in India are overpriced, so Skoda should not rejoice on reading this post....

[mempheS.D]

Originally Posted by Neil.Bhujbal

Q.Why are these stratified engines useless in India ?


A.They need min 95 Ron fuel. Anything less then that has high sulphur
content which damages the new nitrogen oxide storage catcon. The
result is high nitrogen oxide going into atmosphere which the sensor
senses & tells the car to run on homogeneous mode thinking the catcon
is full and needs to be flushed.

So in short the car never runs on stratified charge mode & you don’t get the fuel economy you should be getting.
All you get is just a little more power compared to normal fuel injected petrol engines.

Alright! So we have the TSi engine which is "engineered" better than conventional non-DI engine. Neither do I nor any members who've commented on this post have expressed a contradicting opinion.

I'd like to pull attention back towards the quoted text, irrespective of frustrations or ignorance that a few may have expressed. Since this is a forum where genuity of any piece of information is debated.

Question:
1. So does the TSi engine (say, in a laura) really function in homogenous mode only considering that 91 RON is what's easily available in India ? Or have they been tuned in any other manner so that they can still run on stratified mode irrespective of fuel RON?

2. Before one starts throwing all at the Japs for not imbibing the DI technology in their engines, one must question the root cause? The TSIs are new technology of course. When Skoda and its likes can offer this technology at reasonably the same rates, is it not a valid question to ask as to why the Japs are hesitant to take this step? I'm sure they've given it a thought and have their own reasons to opt out. Upon googling, what I read is that certain octance levels of fuel have been seen to cause exhaust valve erosion. The additional precuations and care (synonymically money) warrants the strategy so far employed by the Japs who've always been known for their problem-free, low-maintenance horses.

[anandpadhye]

Originally Posted by mempheS.D

2. Before one starts throwing all at the Japs for not imbibing the DI technology in their engines, one must question the root cause? The TSIs are new technology of course. When Skoda and its likes can offer this technology at reasonably the same rates, is it not a valid question to ask as to why the Japs are hesitant to take this step?

So can you also enlighten us why Honda is not launching their diesel cars in India? Don't you think questions are valid, answers may not be.

[Aroy]

Actually I am confused. Correct me if I am wrong.

Marketing people will always try to extract the maximum milage even from a mundane phenomenon. What we are talking of is direct fuel injection.

. The Octane number denotes the fuel's resistance to spontaneous ignition. The higher the number the more resistant it is. Higher compression engines need higher octane rating. Now if I am injecting fuel just at the beginning of the ignition cycle; I time it with the spark initiation; do I really need a high octane rating. In my opinion I now do with a lower rating as I am injecting the fuel synchronous with the spark.

. The leaner the mixture, the less pollutants as there is less fuel.

. The leaner the mixture the lesser unburnt fuel, again less pollutants.

. How can Nitrogen and Co2 increase if we are using less fuel. A more detailed explanation should clear this up.

. At higher combustion temperatures a lot of unburnt fuel (if it was normal temparature) will burn, also more carbon monoxide will be converted to CO2 and similarly with nitrous oxides. So in effect there should be less pollution if the combustion temperature is higher than normal.

. With controlled fuel injection; as in CRDI engines; the mechanical stresses due to combustion are not only controlled, but peak stresses reduced, as now you do not need one big "Bang" (fuel explosion), but can do with a lot of smaller "Bangs".

I always thought that the idea of direct fuel injection was to control the combustion process, making it more efficient, thus reducing pollution. With modern computer control, the ECU is capable of supplying just the right amount of fuel for the job - less when the load is less and more when the load is more. Again, the fuel injection can be spread to sustain a longer power stroke, increasing the torque, while containing stresses.

Finally one cannot dismiss the utility of direct fuel injection by citing bad fuel. Why, as ECU become smarter, they can learn from the effect of combustion and adjust parameters, thus extracting maximum from bad fuel. Thus we have a much better system which is tolerant to a wide range of fuel qualities.

These are my personal views based on what ever I have read over the years, and not a result of any rigorous experiment.

[Sutripta]

Hi,
Nice attention grabbing title.

Problem is octane rating, or sulphur content?
What is the effect of sulphur on the NOx cat? Permanent damage? Detected by sensors?
Can someone tell me where in the refining process sulphur is removed from diesel?

ARAI emission test: Doesn't the manufacturer have to give a mileage guarantee?

Could the TSI owners write to the manufacturers and ask for their comments.
Does the scanner throw up any codes? Does the CEL ever come on?

Regards
Sutripta

[Neil.Bhujbal]

Originally Posted by pranavt

You are not paying anything extra for the new technology.

In return, you are getting something that is leaps ahead of most of the trash that is released here with nothing more than a new name or a fancy bumper redesign, take the case of the Honda Civic.

By your own logic, we shouldn't get cars which are very powerful because we do not have the roads or racetracks to exploit the power. I hope you're getting what I'm trying to say.

Whether the technology is beneficial to us or not is a moot point. It is a proven method of fuel injection, one that is much more efficient than what's currently available. The fuel quality will catch up, atleast in Metro cities sooner or later. Some of you may be surprised even by the quality of regular fuel that's currently available. Most of the armchair experts commenting on the "horrible" quality of fuel have probably not got a gas chromatograph report of pump fuel in their hand which they are referring to when the spread their "facts." Or they've handed over their engines to fools who are too stupid to understand what can be done even on pump fuel.

The last statement isn't relevant to most of the public here or most road cars sold today. But I still stand by my belief that any new technology introduced here should be welcomed. Let the Government and fuel companies catch up.

Ok I get your point.

Originally Posted by Vik0728

Amazing info Neil.Bhujbal and what a time to post this vital data.

So Neil, correct me if I'm wrong -
# Basically you are pointing out at the fact that though Skodas, Audis, VW's might come up with Supercharged/turbocharged Petrol engines, their full potential will never be achieved ?
# Is there any proof or data that says these Auto giants are not tuning/building these powertrains according to Indian fuel but are basically global designs ?
# Other than the obvious fuel, do you think there might be another way of ensuring that these engines deliver the optimum results ?

All the best with your project dude and hope I did not sound too investigative, just curious !!

With the normal octane fuel their full potential (in terms of efficiency) cant be exploited.
I know Mercedes does not do anything about it since i work there.
No,other then fuel there is nothing else stopping these engines deliver full efficiency in India.

Originally Posted by anandpadhye

Neil,

Good thread.

But,
Do you want to say that stratified injection actually never comes into play in India at all???
Do you think my Laura TSi will give me incredibly higher FE if I use Speed 97?

When the car's new it does come into play. When it covers some kms (how much in precise i don't know) the sulphur has already started reacting with the storage catcon letting nitrogen oxide go into air which the sensor detects & asks the car to run on homogeneous mode.
Now everything else depends on how much damage is caused to the catcon.
According to whatever info i have with me the mileage as well as performance should increase with 97 octane. Why not try it out ones ?

Originally Posted by v.anand

I agree with pranav here. The technology in Skodas and VWs are not charged at any premium over the competitors. In fact Laura sells at a price less than Civic and Altis with cutting edge technology under its hood. If it has any adverse effects, then I am concerned.

A very nicely presented and comprehensive report by Niel, never understood the differences earlier. I also am interested in knowing whether TSI performs much better with speed 97 available here.

According to what ever info i have on this,speed 97 will increase the power as well as mileage. why not try it out ones ? It wont harm the engine.

Originally Posted by Tats07

Laura 1.8 TSI doesn't need 95 RON fuel. It is also known to be pretty fuel efficient and very powerful. What could be the possible changes introduced by Skoda?

Check the first post in below link. The owner mentions his laura TSI's owner manual asking him to fill 95 octane fuel.

Originally Posted by anandpadhye

I agree.

The latest tech should always be welcome and kudos to Skoda for bringing the TSi before anybody else. I, for one, really enjoy driving my Laura TSi and in one of the YouTube videos about the TSi, I came across the statement that the VW group is striving to make motoring more efficient at the same time not sacrificing driving pleasure. Now, I admire this attitude.

For me, one definate way to check the factuality of the claim in this thread (that TSi is useless in India ...because of our petrol quality) is to use a tankful of speed97 and see if TSi (which is already returning decent FE of around 12kmpl @160kmph, 15/16kmph @100kmph and 9/10kmpl in city traffic), becomes super efficient with speed97 or not. May be one day I will try.

As for the fun part or the driving pleasure, the Hondas and Toyotas do not even come close to the TSi...of course one may claim that it's simply because of the turbo as the Octy TPi/vRS was also huge fun to drive...but I have feeling that TSi is a bit more fuel efficient than TPi.

BTW, Laura TSi has GDI and variable valve timing and 6'th gear -definately not useless for me.... And Laura TSi costs less than the Civic which does not have turbo or GDI or 6'th gear so I did not pay more for GDI even if GDI *MAY* not be active some of the time.

Disclaimer: All cars in India are overpriced, so Skoda should not rejoice on reading this post....

My post title has question marks in the end. I have posted the info i had with me about stratified charge mode engines & how they work. According to their theory of working they dont work to their full potential in India because of the low octane fuel.

So its a question to all, are these engines useless in India ? ? Not technology wise but full exploitation wise.

You should definitely try filling up 97 octane ones & let us know the mileage & power difference you feel.

Originally Posted by mempheS.D

Alright! So we have the TSi engine which is "engineered" better than conventional non-DI engine. Neither do I nor any members who've commented on this post have expressed a contradicting opinion.

I'd like to pull attention back towards the quoted text, irrespective of frustrations or ignorance that a few may have expressed. Since this is a forum where genuity of any piece of information is debated.

Question:
1. So does the TSi engine (say, in a laura) really function in homogenous mode only considering that 91 RON is what's easily available in India ? Or have they been tuned in any other manner so that they can still run on stratified mode irrespective of fuel RON?

2. Before one starts throwing all at the Japs for not imbibing the DI technology in their engines, one must question the root cause? The TSIs are new technology of course. When Skoda and its likes can offer this technology at reasonably the same rates, is it not a valid question to ask as to why the Japs are hesitant to take this step? I'm sure they've given it a thought and have their own reasons to opt out. Upon googling, what I read is that certain octance levels of fuel have been seen to cause exhaust valve erosion. The additional precuations and care (synonymically money) warrants the strategy so far employed by the Japs who've always been known for their problem-free, low-maintenance horses.

According to the theory i have learnt & data i have,when the cars new it will work in starified as well as homogeneous mode. As the sulphur (which is high in our normal fuel) starts to react with the new additional nitrogen oxide storage catcon it reduces the efficiency of storing nitrogen oxide.
This nitrogen oxide that goes out in the atmosphere makes the nitrogen oxide sensor at the end of exhaust system think that the catcons capacity is full & needs to be flushed. So it tells the ecu to run the car on homogeneous mode.

So when your catcon is damaged to a level that it wont even hold little nitrogen oxide from that time onwards your car will never run on stratified charge mode.

Originally Posted by Aroy

Actually I am confused. Correct me if I am wrong.

Marketing people will always try to extract the maximum milage even from a mundane phenomenon. What we are talking of is direct fuel injection.

. The Octane number denotes the fuel's resistance to spontaneous ignition. The higher the number the more resistant it is. Higher compression engines need higher octane rating. Now if I am injecting fuel just at the beginning of the ignition cycle; I time it with the spark initiation; do I really need a high octane rating. In my opinion I now do with a lower rating as I am injecting the fuel synchronous with the spark.

. The leaner the mixture, the less pollutants as there is less fuel.

. The leaner the mixture the lesser unburnt fuel, again less pollutants.

. How can Nitrogen and Co2 increase if we are using less fuel. A more detailed explanation should clear this up.

. At higher combustion temperatures a lot of unburnt fuel (if it was normal temparature) will burn, also more carbon monoxide will be converted to CO2 and similarly with nitrous oxides. So in effect there should be less pollution if the combustion temperature is higher than normal.

. With controlled fuel injection; as in CRDI engines; the mechanical stresses due to combustion are not only controlled, but peak stresses reduced, as now you do not need one big "Bang" (fuel explosion), but can do with a lot of smaller "Bangs".

I always thought that the idea of direct fuel injection was to control the combustion process, making it more efficient, thus reducing pollution. With modern computer control, the ECU is capable of supplying just the right amount of fuel for the job - less when the load is less and more when the load is more. Again, the fuel injection can be spread to sustain a longer power stroke, increasing the torque, while containing stresses.

Finally one cannot dismiss the utility of direct fuel injection by citing bad fuel. Why, as ECU become smarter, they can learn from the effect of combustion and adjust parameters, thus extracting maximum from bad fuel. Thus we have a much better system which is tolerant to a wide range of fuel qualities.

These are my personal views based on what ever I have read over the years, and not a result of any rigorous experiment.

You dint read the topic carefully. You dont need high octane fuel for the engine but for the exhaust system of these engines to work efficiently.
(sensor on the exhasut can tell the car which mode to run on)

Normal fuel has high sulphur content which reacts with the new catcon in these startified engine exhausts.

High temperature during combustion make nitrogen react with oxygen resulting in nitrogen oxide.

Please go through the topic ones again.

Originally Posted by Sutripta

Hi,
Nice attention grabbing title.

Problem is octane rating, or sulphur content?
What is the effect of sulphur on the NOx cat? Permanent damage? Detected by sensors?
Can someone tell me where in the refining process sulphur is removed from diesel?

ARAI emission test: Doesn't the manufacturer have to give a mileage guarantee?

Could the TSI owners write to the manufacturers and ask for their comments.
Does the scanner throw up any codes? Does the CEL ever come on?

Regards
Sutripta

Problem is the low octane fuel which has high sulphur content.
This sulphur reacts with the new catcon in theses engines.
These engines have two catcons.

The Nitrogen oxide storage catcon uses barium carbonate which reacts with sulphur. These is a sensor placed after this second catcon to check its functionality. So when nitrogen oxide passes this catcon the sensor detects it & tells the car to run on homogeneous mode.

[cyberwhizs]

@niel

Pardon my ignorance but arent these so called efficient engines delivering dysmal fuel efficiency figures ( i.e. < 8kmpl) in the real world. There was a furore when some environment minister made a remark on fuel efficiencies of german made SUVs and luxury cars.

There are threads where in people have reported efficiencies in the order of 3 - 5 kmpl. Considering the fact the most of the cars are essentially meant for the road and not for the race track, in what way are these fuel guzzlers classified as technologically advanced.?

[sgiitk]

Originally Posted by Neil.Bhujbal

Q.Why are these stratified engines useless in India ?


A.They need min 95 Ron fuel. Anything less then that has high sulphur
content which damages the new nitrogen oxide storage catcon. The
result is high nitrogen oxide going into atmosphere which the sensor
senses & tells the car to run on homogeneous mode thinking the catcon
is full and needs to be flushed.

95RON is the standard for Premium in Euro III & IV. I do not see how can 95RON against the 91 Standard have anything to do with Sulphur. The specification vis a vis Sulphur are the same for Standard and Premium.

[Neil.Bhujbal]

Originally Posted by cyberwhizs

@niel

Pardon my ignorance but arent these so called efficient engines delivering dysmal fuel efficiency figures ( i.e. < 8kmpl) in the real world. There was a furore when some environment minister made a remark on fuel efficiencies of german made SUVs and luxury cars.

There are threads where in people have reported efficiencies in the order of 3 - 5 kmpl. Considering the fact the most of the cars are essentially meant for the road and not for the race track, in what way are these fuel guzzlers classified as technologically advanced.?

I have no idea which German made SUV's you are talking about.

The cars which come with these TSI,CGI engines are mostly sedans & give pretty good mileage & high power when compared to normal fuel injected vehicles.

Originally Posted by sgiitk

95RON is the standard for Premium in Euro III & IV. I do not see how can 95RON against the 91 Standard have anything to do with Sulphur. The specification vis a vis Sulphur are the same for Standard and Premium.

Sulphur content in 95 octane fuel is less then 10 ppm compared to 15 ppm which is found in 91 octane fuel.

[Shivank]

Hi again, Neil.

Very interesting thread. I am just glued here!

I did a fair bit of Googling and after that it seems these engines can't definitely be tagged as useless! As per the information I have gathered, manufacturers tune engines as per the fuel available here.

In Europe or anywhere else where 95 RON is the default choice for these cars, stratified or lean mixture, lets assume, is set to be at 1:40 (Fuel:Air) against the stoichiometric ratio of 1:14. Under light loads this is good for fuel consumption. Right?

Now come back to India. Because 91 RON is more popular here than 95, the stratified mixture is now made to run much richer compared to what's offered in European cars, i.e, instead of setting stratified mixture at 1:40 manufacturer now changes the Fuel-air ratio as per the the quality of fuel used here. Let's say, reduces it from 1:40 to 1:25 or 1:20. Getting my point?

This way, the engine still runs leaner/saves fuel at light loads (considerably). And all that without harming the engine or cat-con life.

PS: Hope, I made sense here. I am just sharing what I understood.

[Aroy]

Some interesting links on pollution
Tier 2 Gasoline Sulfur Program | Fuels and Fuel Additives | US EPA
Reformulated Gasoline (RFG) | Fuels and Fuels Addtives | US EPA
http://www.meca.org/galleries/default-file/sulfur.pdf
http://www.iocl.com/Products/MS_BS_I...0_Current_.pdf
UK Fuels - Change in the level of Sulphur in BP Fuel

At present both 91 and 95 RON fuels have same sulfur - 50 ppm. The 97 RON is supposed to have 10 ppm.

As all the high end petrol vehicles use high compression engines, they will benefit anyway from 97 RON fuel.

[~~h]

brilliant write up, thanks for sharing.

Originally Posted by Neil.Bhujbal

2)Its the sulphur content which reacts with 'nitrogen oxide storage catcon',destroying it & resulting in nitrogen oxide going into atmosphere.The sensor in the exhaust end reads it & thinks the catcon is full to its capacity & needs to be flushed.For this it tells the ECU to run the car on Homogeneous mode (power mode) so that the cat con can be flushed out.This way the car never actually runs in stratified mode.

Qn: does it mean if you disable the sensor or fool it some way the engine will work in stratified mode ?
Of course it's not good for the environment but with the low quality fuel that (or frequent cat con flush) seem the way to go.