[Sutripta]

Strange to note that in the week since this thread went up, the OP has nothing further to say!

Originally Posted by Rahul Rao

[/i]In theory, a engine with 100 bore and 100 stroke 785cc/cylinder should be twice as effecient in (gms/hp) as a 50 bore 50 stroke 98cc/cylinder. In effect it should put out 8 times the power with only 4 times the fuel burned at the same Rpm.

Which theory?
So we can expect huge single cylinder industrial engines?

Regards
Sutripta

[Rahul Rao]

Originally Posted by Sutripta

Which theory?
So we can expect huge single cylinder industrial engines?

Thermodynamics.


No I expect manufacturers to choose a engine dimension that suits the vehicle they make, and the usage the vehicle is put too.
Planning engine size as per taxation even though it may be inefficient and under powered is wrong.
Secondly having engine options for vehicles having multiple uses will also be good.
If a city dweller buys a mid sized SUV for his trips on bad roads, occasional offroading and also highway use may choose a 2.2Lit turbo diesel which puts out 140 bhp or so, and cruises comfortably at 100 with engine ticking away at 1800 rpm, but has the grunt to give a quick overtake when downshifted and floored.
Some one in the hill states, a tea estate manager or a plantation plantation in Chikamagalur etc may prefer a version of the same SUV with a 3 Lit diesel tuned for 200 NM torque and less than 80 Bhp as his car is rarely going be shifted into the top gear and see 3 digit speeds.
Another enthusiast may prefer a 200 BHP petrol version too.

Today we have only M&M that gives the option of the Thar DI 4x4 with its 2523cc 63bhp engine which has a very decent low end for that kind of operation.

Rahul

[prakhar1998]

Instead of attempting to be a nanny state with random numbers deciding the fate of so many factors in such a huge growing market, why doesn't the government instead rely on promoting technologies that actually have been proven to make a difference.

The most insane thing that boils my blood each and every time is the increased tax on hybrids. Promoting heavy subsidies on hybrid technologies would not only make choked cities all over India a lot more bearable (Proper hybrids would emit 0 pollution in bumper to bumper traffic), but also promote local lithium ion battery manufacturing units helping us get to EVs significantly faster.

While downsizing has been a trend globally, it has occurred organically where manufacturers realised they can save money by making smaller engines with Turbos. Arbitrary numbers again don't in any way help make engines smaller.

What if I as a manufacturer realise that I would be able to make a much more balanced 1300cc engine, which will perform more efficiently in all situations, but end up just making it 1200cc because I would rather sell a cheaper car, with lower taxes.

But then again, efforts in more developed countries haven't been significantly more successful with manufacturers such as VW using dirty tactics to defeat the govt. regulations. Any regulation would have potential loopholes that profit hungry corporates would go to any extent to exploit.

[Sutripta]

Could you be a bit more specific please. Just saying

Originally Posted by Rahul Rao

Thermodynamics.

is about as enlightening as saying "by the laws of physics".
I know the going may get tough, but we'll try to keep up.

In the meantime could you give the mathemetical relationship by which we can arrive at the fuel used part as we go from a multi cylinder setup to a single cylinder setup of the same overall cc? Maybe we can start from there.

So as not to get diverted/ loose focus with issues such as these

No I expect manufacturers to choose a engine dimension that suits the vehicle they make, and the usage the vehicle is put too.
Planning engine size as per taxation even though it may be inefficient and under powered is wrong.
Secondly having engine options for vehicles having multiple uses will also be good.
If a city dweller buys a mid sized SUV for his trips on bad roads, occasional offroading and also highway use may choose a 2.2Lit turbo diesel which puts out 140 bhp or so, and cruises comfortably at 100 with engine ticking away at 1800 rpm, but has the grunt to give a quick overtake when downshifted and floored.
Some one in the hill states, a tea estate manager or a plantation plantation in Chikamagalur etc may prefer a version of the same SUV with a 3 Lit diesel tuned for 200 NM torque and less than 80 Bhp as his car is rarely going be shifted into the top gear and see 3 digit speeds.
Another enthusiast may prefer a 200 BHP petrol version too.

Today we have only M&M that gives the option of the Thar DI 4x4 with its 2523cc 63bhp engine which has a very decent low end for that kind of operation.

I had mentioned

Originally Posted by Sutripta

So we can expect huge single cylinder industrial engines?

In fact, to simplify even further, let's remove yet another parameter (rpm). So genset engines.

Regards
Sutripta

[Rahul Rao]

Originally Posted by Sutripta

Could you be a bit more specific please.
In the meantime could you give the mathemetical relationship by which we can arrive at the fuel used part as we go from a multi cylinder setup to a single cylinder setup of the same overall cc? Maybe we can start from there.

When you increase the size of a cylinder, both (bore) cross section area and (stroke) height. Assuming it's a square engine. The exposed surface area increases in proportion to twice the square, where as swept volume increases in proportion to the cube.
This effects in less of the heat being lost to atmosphere, and more of it being used for expansion. Secondly the weight of the reciprocating mass (piston and connecting) also do not increase in the same proportion as the swept volume.

Originally Posted by Sutripta

In fact, to simplify even further, let's remove yet another parameter (rpm). So genset engines.

RPM is also a very important factor, larger slower engines are more effecient in gms/hp/hr than smaller faster ones.

PS. Refreshing theory 22 years after passing out of engineering, and 18 years after exiting is difficult.

Rahul

Rahul

[McLaren Rulez]

Personally, I'm quite annoyed because it killed great combinations like the Polo 1.6. It did give us the stunning GT TSi but I'd much rather have the mechanically simple 1.6 for 50k more if I could.

[Sutripta]

Originally Posted by Rahul Rao

When you increase the size of a cylinder, both (bore) cross section area and (stroke) height. Assuming it's a square engine. The exposed surface area increases in proportion to twice the square, where as swept volume increases in proportion to the cube.
This effects in less of the heat being lost to atmosphere, and more of it being used for expansion. Secondly the weight of the reciprocating mass (piston and connecting) also do not increase in the same proportion as the swept volume. l

If one uses this as the premise, and extrapolates, one lands up with (depending on ones point of view) thats wonderful/ thats absurd.
eg. Start of with any engine. Calculate power, specific power, specific fuel consumption.
Now double bore and stroke. cc (= power) goes up 8 times (2 cube), fuel consumption goes up 4 times (2square). So specific power remains the same, specific fuel consumption halves.
Continue till you have engine power approaching infinity, specific fuel consumption approaching 0.
Your choice of view!

This whole 'theory' is based on the assumption that the ONLY loss is conduction heat loss through walls of the combustion chamber.
Actually the internal combustion engine is a disaster when it comes to efficiency. The cycles (Otto/ Diesel/ Miller/ Atkinson/ whatever) theoretically have pretty poor efficiencies, and these are theoretical maximums. Every real world effect is only going to subtract from these.

RPM is also a very important factor, larger slower engines are more effecient in gms/hp/hr than smaller faster ones.

True. But that was not the focus of my point when I talked of comparing genset engines.

Genset prime movers generally have three working RPMs - 0, on load (which can vary by approx 3% full load to no load depending on the quality of the governor), and an inbetween transitioning rpm (popularly called idling) used for warm up/ cool down.
Going by the reasoning mentioned before, one would expect all/ most genset engines to be single cylinder contraptions with cylinders sized to produce the power needed.

Since manufacturers quote a specific fuel consumption figure (at least for full load. Some manufacturers give a table or a graph for part load), one can very easily compare specific fuel consumption figures for different engines, removing a lot of the extraneous factors (like rpm) which affect the engines deployed in automobiles.

Regards
Sutripta

[Rahul Rao]

@Sutripta You can never get infinite effeciency.
Massive Ship engines made by Sulzer with a 965mm bore and 2.49M stroke are the only practical engines to have achieved 51.7% thermal effeciency, but the clame is 50% or 126 GM/HP/Hr.
Man has a engine with 54% effeciency but it's need of very high refinement level of diesel doesn't make it very usable.
Approx 2Lit per cylinder 12 / 13 lit i6 engines used in heavy trucks can manage a 43% or 44% thermal effeciency.
More common smaller 0.55 Lit/ cylinder or 2.2/Lit 4 cylinder engines can manage 26% thermal effeciency, but below that the thermal effeciency is quiet pathetic.

Among other factors engines with a stroke longer than the bore can have a fractionally better effeciency, but in a very narrow speed band, while squarer engines can manage a slightly lower peak effeciency but on a descently wider band.

Every manufacturer has to settle for a practical size, and number of cylinders, as no of cylinders affect balance, need of counter weights, etc.



Rahul

[RaghuVis]

Guys.. One question.. Which was the first sub 4m CSUV released in India? I thought it was ecosport but some say it's premier Rio.. Can someone confirm pls.. I guess the first Sub 4m car was Tata Indigo

[deep_bang]

Originally Posted by RaghuVis

Guys.. One question.. Which was the first sub 4m CSUV released in India? I thought it was ecosport but some say it's premier Rio.. Can someone confirm pls.. I guess the first Sub 4m car was Tata Indigo

It was definitely not ecosport. When I bought my Quanto, ecosport was not yet launched but Rio was and it was, if I remember correctly, already discontinued by then.

[Brumby]

I don't need to mention here which car maker which benefitted the most from this rule. They made a lot of tin boxes of different shapes and sizes within 4m length, plonked the same engines with various states of tunes into them and lead the auto industry in terms of sales and profits in India. Wonder if our government did not have this rule what would have been the fate of this carmaker.

I agree with SU1978 here that the rules are made and modified to satisfy the vested interests of one particular car maker which claims to have put Indians on wheels.

This rule is the reason why we rarely get to see genuine cars that satisfy a petrolhead, and if some carmakers launch them here, they fail miserably in terms of poor sales volumes due to exorbitant taxes that are levied upon them.

[kapilvgupta]

I believe even though the goals stated for the sub-4m/engine capacity rule were less than ideal, they did help with some very important things:

• cars/engines being developed locally or specifically for the Indian market
• keep production costs relatively low

I don't believe the number of cars being sold in the country has much to do with this policy nor can this policy be blamed for the lack of roads available per car. These issues, I believe are mainly due to growing per capita income and lack of infrastructure growth.

Going forward, I think the govt. should tax vehicles based on

1. emissions (carbon/overall)
2. value of non-renewable resources used during production
3. end-of-life cost or recycling cost
4. parking space required

In addition to the above, I believe, the govt. should provide incentives for local production or 'green' technologies...

[swami69]

I picked up this thread while looking for some other information.

As a buyer, i think i am benefited by this rule and the manufacturers have given me options to choose. My requirements were

Spacious car from inside (Most Important)
Adequate safety features
Descent driveability
Automatic
@ 10L OTR
New Car with Warranty
Petrol / Diesel - Ok
Looks - it is Ok if does not look gorgeous, but functional is important

With all above, I was able to zero in on Honda Amaze 2018 which fits all my above requirements adequately and in my budget. Two more points to my benefit are

Since the ex-showroom is less than 10L, the TN road tax is only 10% else it would be 15%. Also, i am sure the insurance base premium is lower due to the fact it is a 1.5L engine.

If Honda has not produced Amaze, then exactly in this scenario, i would either have a Jazz or a City (just as an example from Honda Stable) and IF in case i do not prefer a Hatch Back, then City is around 16L OTR. I think Amaze is 80 - 85% of City at probably 65% of the price. I am sure there are many like me whose requirements fit these Boot fitted Hatchbacks

Swami

[SoumenD]

Originally Posted by RaghuVis

Guys.. One question.. Which was the first sub 4m CSUV released in India? I thought it was ecosport but some say it's premier Rio.. Can someone confirm pls.. I guess the first Sub 4m car was Tata Indigo

The first sub 4m sedan was Indigo CS and among sub 4m CUVs Rio indeed came in before ecosport, even quanto I guess. Gypsy was slightly more than sub4m so doesn't enjoy the benefit I believe.

Originally Posted by swami69

I think Amaze is 80 - 85% of City at probably 65% of the price...
Swami

Well, if this sub 4m rule wasn't in place the price difference between CITY and AMAZE wouldn't have been what it is today. All cars would be taxed similarly leading to probably no Amaze at all and CITY at maybe 20% lesser price.

In that case just like other countries CITY, VERNA(ACCENT worldwide) would have been compact sedans in India as well. And cars like i20, punto wouldn't carry the anaemic 1.2L engines

[nakul0888]

It did not go far enough. It made small cars too affordable (among the lowest-priced in the world) and no government paid any attention to public transport.

So how is this motorists fault? India's private sector has made enormous progress, its people began making more and more money, they buy more and more cars filling up the govts coffers with road tax, excise duties, vat, and the Govt fails to build up the infrastructure because in most cases its run by useless corrupt imbeciles and the fault of all this falls on the head of motorists and cars. You can give the people running the govt now 100% road tax or 100% GST and no miracles in infrastructure would happen. I can guarantee that.

Yes, and that's a bad thing.

Yeah because screw the aspiring middle class guy right? How dare he dream about some comfort and security of a car for him and his family. Let the filthy peasant and his family continue using the motorbike on dangerous Indian highways. Who cares what happens to him.

Because foreign countries have better public transport and strong disincentives for cars.

Some countries like singapore, denmark may have huge tariffs on cars. But they are oddities. What about USA, Canada? These countries are huge in land size , have a fraction of the population of India and they built up their infrastructure without punishing their motorists. Maybe we ought to look up to these countries instead.

It is time to tax all cars brutally. I speak as a car owner who tries to avoid using it (my preferred mode of travel is bicycle, 15+15 km/day, yes it can be done and you don't have to be an athlete to do it, it's actually faster than driving during peak hours).

As if cars arent already taxed brutally in India. In some cases almost half the value of car consist of money going to the govt. But thats not enough for you. You want it to be taxed even more brutally. You want cars to be out of reach for most of the people. Lucky you then having an option of owning a car, just in case.

Has it ever crossed your mind that some people cant cycle 30 km a day and NEED a car to get where they want to go to earn a livelihood? And what about emergency conditions? My father fell seriously ill just last week. He blacked out, had to be carried to our car by my family, and driven over to the hospital. Should I have just put him on the back of my cycle and have me cycle over with my unconscious father to the hospital instead? Or should me and my family wait for what 20-30 mins for the taxi or ambulance to come while he is on the floor unconscious, possibly dying?

And what about when you want to go somewhere with your wife and children? And what if its late at night? You seriously suggesting all of them to take public transport in our country when they could under market conditons afford a car ?

We need not just taxes at purchase time, but London-style congestion charges in cities, Italy-style zones where only residents may enter with cars at risk of stiff fines, and above all, sane parking charges commensurate with the real estate value of the space occupied by a parked car.

And, of course, plough that money into public transport, bike lanes, etc.

Yeah as I already said before, you can donate 100% of the value of the car and even more in taxes to to the govt and you wont see any improvement in infrastructure. All the money will 100% get wasted, looted by our dear netas.

No Indian government is going to do any of this, the car lobby and the car-owner lobby is too powerful.

. You can criticize the motorists in India for their rash driving and zero traffic sense which in most cases lead to jams. You can criticize the manufacturers for malpractices. Im all in for both. But the failure of Indian govts at state level and centre level to build up infrastructure does not fall on the heads of car owners or manufacturers