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Old 4th January 2008, 20:39   #91
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my answer in bold!

just so that I know what answer you are looking for....what makes you doubt a diesel?

NOthing now!!
youve cleared it all up ( i was misled by mechanics that seemed to be of the opinon that diesel engines if less driven - "karaab ho jaate hain aur maintenece nikalege" )
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Old 5th January 2008, 19:51   #92
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Originally Posted by pgsagar View Post
no matter how much improved diesels have become these days, there are other issues like increased tyre wear, more regular suspension overhauls, body rattles due to vibrations and not to mention the periodic maintenance of injectors, pumps etc.
The total power of petrol is miniscule compared to diesels (this includes, trucks and other engines)

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and god forbid if timing belt snapped or a pump needed replacement then it would cost enough money to negate the fuel economy.
That way we can say that petrol being more combustible (flash point is lower) and is more risky to drive (the loss of life can negate everthing in life)

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also, these modern CRDi engines of verna, getz and swift that every one is going so gaga over will lose their charm after 70-80,000 kms. they do not run as fast and as efficiently after this mileage. i saw it in many accent crdis. some problem or the other starts surfacing to the point that people tend to palm 'em off.
You really hate diesels. Anyway, as per data available, the problems surfacing are more due to other reasons than diesels (just find the old amby taxis which have run more kms than most of the private petrol owners and many are still running)

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the petrol engines on the other hand, even abused ones, run the same even after 2.5 lakhs. if diesels are really so good then why are manufacturers still making petrol cars?
the largest IC engine on order is diesel and going to produce power about 115,000 PS. These engines are completely camless (that is even for exh valve you don't have cams), they have VTEC etc etc. However as mentioned before, to scale them to a small size to fit in a car, is a very tough job (you can scale them easily, but cost of the car will then be more than twice of petrol ones). And you can see that current trend (where permitted by authorities) is for diesels all over the world. It is just a question of finding the technology to make it affordable to people.
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Old 5th January 2008, 21:02   #93
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Originally Posted by NOTORIOUS View Post
i have a elantra crdi with my friend which has clocked 135k+ and still the same performance like new.the car is only in the hands of me and my friend . i strictly believe that it purely depends on how you keep the car.

OT : during the last visit to a hyundai service center in punjab, the service people showed me a blue coloured elantra crdi which has clocked 267k+ kms ,they say that it has the same pickup as new with +- 5 to 8% diffrence.the car is there for left rear door replacement.
That is reassuring to know! I have one too, and it is just past 70K. Till now, have always sold cars around 2.5 to 3 years. For the first time, I am seriously considering keeping the car for a lot longer. Not only that there is no performance loss in the engine, I think it only got better. And of course, I really cannot think of anything else in Diesel(addicted to the Torque) which will substantially better the car and its engine(+ Petes), in anything less than 30lakhs...

And as for the "technical truth", I think I *like* diesels better now, after some 2.5 years with the Elantra CRDi. Even if the diesels cost more to maintain, I would still buy them. Of course, they don't cost more to maintain, and nothing beats the fun of being pushed into the seat every time you gently prod the throttle.

What I would like to see bettered in a diesel? More revs to play with. Maybe someday somebody would figure a diesel plant which will rev well to 7K rpm?
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Old 7th May 2008, 09:44   #94
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Default Driving petrol versus diesel cars

Folks,

The reason for this query arises from the fact that I have had a Safari for a year now, its 14000 kms old and is still smoking. Concorde motors have tried cleaning air filters, cat con, changing the timing etc, but to no avail. Just 2 days after a smooth performance, its back to black smoke when I try to accelerate a little harder.

Now, to the question: I have driven M800, Zen and Honda City for over 7 years, I have not really changed my driving style after moving to a diesel vehicle - is there any need to change? How different is driving a diesel vehicle to a petrol vehicle??

Thanks!
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Old 7th May 2008, 11:48   #95
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You didn't mentione what model of Safri you have. Is it the 3.0L DICOR? Maybe your injectors are getting clogged (bit unlikely) or the ECU needs a remapping.

Try adding System D injector cleaner at the next tankfull. This should also help.

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Originally Posted by wanderlust View Post
Folks,

The reason for this query arises from the fact that I have had a Safari for a year now, its 14000 kms old and is still smoking. Concorde motors have tried cleaning air filters, cat con, changing the timing etc, but to no avail. Just 2 days after a smooth performance, its back to black smoke when I try to accelerate a little harder.

Now, to the question: I have driven M800, Zen and Honda City for over 7 years, I have not really changed my driving style after moving to a diesel vehicle - is there any need to change? How different is driving a diesel vehicle to a petrol vehicle??

Thanks!
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Old 7th May 2008, 13:54   #96
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Originally Posted by notorious
they say that it has the same pickup as new with +- 5 to 8% diffrence.the car is there for left rear door replacement.
More power comes out of a well used engine??
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Old 7th May 2008, 16:25   #97
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Quote:
Originally Posted by nitrous View Post
More power comes out of a well used engine??
ok ok... forget that + thingy... what he means is that a little here and there
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Old 23rd May 2008, 23:50   #98
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[quote=hellspawn;662452]the diesels being priced 70-80k more than the petrols is actually a marketing strategy.

Well, I think this is simplistic. If this were so, many companies would opt to just sell diesel engines and not bother to make petrol at all..
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Old 17th September 2008, 11:46   #99
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I am an automobile engineer and was always interested to decide the best Car buy based on facts and figures. After studying a lot of ways and doing considerable calculations to decide between Petrol and


Diesel I have come to a certain conclusion on which the following review is based. Decision is based on Financial viability only. (Please make your own excel sheet for calculation purpose its the only way to get your answers fast and allow for iterations)
Suppose two persons purchase car on the same day 1diesel (CAR A) and the other petrol car (CAR B). As per your requirement decide at what kilometers you will sell the car, Say 85000 kms( kms of car ownership).
There are two calculations required for deciding-One is finding out the Breakeven kms and the other the Final cost of the car for 85k kms.

(Note its necessary to take the Car A as diesel car in the following calculations and Car A price should be more than Car B, otherwise it will give wrong results. The basic funda in following calculations is to break each cost on per kilometre basis)

Calculation 1: Find Breakeven point or Breakeven kms
As one has already paid more money for the Diesel car, At what kms will the Diesel car start giving gains as compared to petrol. Make a equation: Let Y be the breakeven kms, At Y kms the total cost of CAR A will be equal to Total cost of CAR B
Solve following equation to get Y kms which will decide the no. Of kms to be driven for a diesel vehicle after which it will start making profits compared to a petrol car.
Equation: Total cost of Car A + Per km running cost of Car A * Y kms = Total cost Car B + Per km running cost of Car B * Y kms.

Total cost of CAR A= Purchase cost of CAR A + Interest + Depreciation
Interest: Interest on the amount: [Purchase cost of Car A minus Purchase cost of Car B] for N no. Of years of car ownership.
(Say 8.5% Interest on 1 lakh rs difference for 8 years)
N no. Of years = 85k kms/ Kilometer covered by car in 1 year
Depreciation: Assuming 20% depreciation on the above amount
(so 20000rs on 1lakh)

(Note: Donít forget to add the above interest and depreciation which is very important for the calculation to get the true picture to come in front. People forget this and do wrong calculations)
Per km running cost = Per km fuel cost +Per km maintenance cost.
Per km fuel cost = Fuel cost for 1 litre / Car mileage (in kms) for 1 litre of fuel.
Per km maintenance cost = 1 Servicing cost/ Service interval in kms (For eg. service of car at every 5000 kms)
(Note: Earlier the service interval for a diesel car was 5000 kms and for petrol was 10000kms but now modern Diesel engines have less maintenance and are getting nearly equal to the Petrol Engines. But off course when Diesel Engines give way, they lead to costly repairs compared to petrol. People often forget the maintenance cost and get wrong financial calculations. For eg you can add Rs 16000 for Diesel Pump Calibration for a Indica Diesel engine at 70-80k kms so 16000/70000 becomes the additional maintenance cost per km for a diesel engine)

Calculation 2: Find Final cost of Car A and B.
Final Cost of Car A = Total cost of Car A (calculated above, Not Purchase cost) + Fuel cost for Car A *85000 kms
Final Cost of Car B = Total cost of Car
B (calculated above, Not Purchase cost) + Fuel cost for Car B *85000 kms
Solution:
From Calculation 1 you will get breakeven kms, if breakeven kms are more than the kms at which you will sell the car, no use buying Diesel Car.
From Calculation 2 if the Final cost of Car A is greater than the Final Cost of Car B then no use taking Diesel. Carefully carry out the above two calculations and you will never make a wrong decision financially. If the Final cost of Diesel Car is only less by say 25000 rs as compared to Petrol Car it doesnít make sense to buy Diesel car, because often Diesel engine due to more vibration give more work on suspension and alignment in long term.
Assumptions: 1) Depreciation on the total cost of both vehicles is not taken here to simplify the equation.
2) Resale value of both vehicles after 85k kms is also not considered. If you add the above points in the above equation you have a perfect evaluation whether to purchase a diesel or a petrol car.

If you have any more things to add to the above calculations, please mail me at amit_purohit20@rediffmail.com or on my mouthshut id. I would be more than please to send a copy of the excel sheet I made for your calculation purpose.
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Old 17th September 2008, 13:52   #100
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Boss,

the economic thread is separate. Search for posts from "Tech" last march.
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Old 18th September 2008, 10:33   #101
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Originally Posted by reignofchaos View Post
I'm curious on what basis do you choose diesel if the fuel costs are the same. I would not even look at diesels then.

First of all its the racket that diesels make compared to the refinement of a petrol. The NVH of diesels though having improved of late is still no way close to petrols.

Secondly the way modern CRDi engines deliver power is kinda ridiculous. The power band is really narrow, typically between 2000 and 4000 rpm. At any engine speeds below that, the car refuses to move. Its as if the engine says... hey I'm sleeping, don't pester me . Agreed there's a huge torque wave when in the power band but inside city driving is painful. Its the same with verna, optra, VW Passat, Swift D and every other diesel i've driven. The only notable exception is the octy.
I beg to differ, all the small diesel hatches I have driven don't even require you to touch the accelerator until you want to shift from second to third.

Case in point: When I am driving my Indica Turbo in heavy traffic, I don't touch the accelerator. When I am crawling up a slope in traffic, I don't use the accelerator, only the clutch. Same with the swift and Getz CRDi. I can also jackrabbit off a traffic signal as it doesn't really take a noticeable amount of time to get from 1k to 1.75k RPM.
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Old 18th September 2008, 11:33   #102
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when the car in front moves suddenly and a gap forms, and an autorikshaw from the left/right tries to move into the gap, and you want to cut him off , will the indica move like a petrol? No it wont. You will have to floor it , and it will move slowly initially, and pick up speed only later. At least thats my experience. I hear the indica DiCor has improved in that aspect

The roar from the engine scares away the rikshaw guy, but thats another matter
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Old 18th September 2008, 12:40   #103
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Originally Posted by greenhorn View Post
when the car in front moves suddenly and a gap forms, and an autorikshaw from the left/right tries to move into the gap, and you want to cut him off , will the indica move like a petrol? No it wont. You will have to floor it , and it will move slowly initially, and pick up speed only later. At least thats my experience. I hear the indica DiCor has improved in that aspect

The roar from the engine scares away the rikshaw guy, but thats another matter
Sorry, that's where you are mistaken, wih the petrol, I would have to rev the engine and then release the clutch, with the diesel I just have to pop the clutch, in fact I don't even have to release the clutch gently, unlike the petrol, I haven't stalled out yet. The common misconception is that turbodiesels are slow until the turbo spools up, it's true only for higher gears. Also, I don't have to "floor it", not even when I'm doing 130+ on Palm Beach road.
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Old 18th September 2008, 15:27   #104
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Originally Posted by teknophobia View Post
Sorry, that's where you are mistaken, wih the petrol, I would have to rev the engine and then release the clutch, with the diesel I just have to pop the clutch, in fact I don't even have to release the clutch gently, unlike the petrol, I haven't stalled out yet. The common misconception is that turbodiesels are slow until the turbo spools up, it's true only for higher gears. Also, I don't have to "floor it", not even when I'm doing 130+ on Palm Beach road.

there is no revving involved in a common rail. atleast not to the extent of that needed in a petrol.
i never have to floor the pedal, however hard i'm accelerating, i get enough pulling even before the pedal touches the floor. provided i'm in the right gear.
even at 3000rpm, most petrols are struggling to keep up.
@greenhorn- yes the dicor is better that way.
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Old 18th September 2008, 16:24   #105
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also, these modern CRDi engines of verna, getz and swift that every one is going so gaga over will lose their charm after 70-80,000 kms.
Though I don't agree with most of your argument, and another member has already addressed some points, I share the same concern as you on what kind of maintenance issues crop up in the longer-term on modern diesels. I have seen many a Merc cross well over 2.0 lakh kms with a common-rail. However, I am eager to know how the Swifts, Vernas and other recently launched <10 lakh rupee diesels perform over 1 lakh kms. The first suspect will be the fuel pump that is working much harder than in an old-school DI / IDI engine. The only way to tell is going to be via long-term ownership reports on Team-BHP. I can hardly wait!

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Originally Posted by tadukuttan View Post
What I would like to see bettered in a diesel? More revs to play with. Maybe someday somebody would figure a diesel plant which will rev well to 7K rpm?
Honda is answering your prayers. Redline beyond 6,000 rpm. 140BHP + 340 NM of torque

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