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Old 13th March 2010, 23:44   #46
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Hey man! did say Urinejet??
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Old 14th March 2010, 00:06   #47
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Multijet is the Future of Diesel economy

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Originally Posted by greatmana2000 View Post
Regrdless of the "engine of the year " awards by motor mags .. we have to go by the engines . It would not be difficult for even the tata engines to win " engine of the year" awards .

Before we talk about ford and fiat , we need to know that the tdci engine was designed by peugeot in principle .

peugeot engines are supposed to be the best diesel engines on various parameters

Longer service life
less maintenance
better design

It would be easy for manufacturers to design engines for a specific purpose ( for example racing or for an agricultural tractor ) , but to design a drive train for a long lasting car it is a real challenge .

A drive train essentially means engine , clutch , gearbox . All these have to be in sync with each other .

It would be a waste of time discussing only engines when essentially the driveability of a car depends on many more factors .

In my opinion the best designed drive train would be the tdci rather than the multijet , quadrajet and may to come "urinejet"
I have already driven my palio multijet for 15K km and do not see any major expenses on the diesel engine as claimed by petrol enthusiasts

Dont like the diesel engine noise however awesome fuel economy,strong strudy build and massive torque on uphill climbs keeps me playing my car muzik system harder without any complains

Punto has challenged all other diesels a step further in refinement and handling

Fiat Multijet is a universal diesel engine now with swift,indica using it however TDCI would be expensive to maintain looking at Ford is the only company using the engine in long run
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Old 15th March 2010, 00:32   #48
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Fiat Multijet is a universal diesel engine now with swift,indica using it however TDCI would be expensive to maintain looking at Ford is the only company using the engine in long run

Ofcourse ford will only use it as they are the rightful owner of the trademark.


Its funny that this discussion had to run four pages and some fifty posts.

Both are same thing.
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Old 15th March 2010, 22:45   #49
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Driveability Issue

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SirAlecProblem is why do people flat out in low gear while climbing hills. Be gentle on your right foot.

we are hill people so its like this, While climbing, (in swift) we normally keep it in 3rd. we don't change to fourth even if its eager to go for it. during over take some times if you have a bus in front we normally shift to second and match the speed with that of bus and wait for the space to overtake and again change to third during overtake.
Sir, Swift diesel engine is way too much an improvement when compared to Indigo/Vista TDI engine. If i be gentle on accelerator the speed at which the vehicle climbs the incline is very very slow and it becomes miserable.And I do not floor the accelerator.Fact is Vista TDI engine is not as free revving as compared to Swift diesel. Just push the engine above 2000 rpm and it starts to sound coarse,you reach 2500 rpm and now the engine starts crying harshly-beyond that you really cannot accept the engine noise and harshness.You feel that you are outlimiting your engines capacity.
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Old 15th March 2010, 23:58   #50
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Originally Posted by amit_purohit20 View Post
Vista TDI engine has very less torque below 1500rpm. On some hills if we drive on 2nd gear I feel that the engine has been revving too much(engine noise sounds very coarse as its not a free revving engine like petrol).So I shift to 3rd gear and then the engine rpm falls below 1500rpm and I am doomed the response is so bad now that I hate driving in such conditions.But at the same time I dont like driving in 2nd gear, it feels like I am driving at high speed in 1st gear-the engine making too much of a racket(noise) so dont feel like revving the engine at 2500 plus rpm. This is a serious driveability issue I feel so. The second gear is too low and 3rd too high.
You need to keep the revs above 18 or 1900 rpm to be comfortable. I switch off the aircon on the ghat sections. If your RPM drops you need to downshift. You can't do a thing about the highspeed in a lower gear so don't let the noise bother you.. You need go up to about 3k rpm before you change to the next higher gear. Its all because the torque comes on so late. I think the newer engines have their torque coming on early though. Good car to drive on the straights but in city and on the steep hills I know what you mean.

Last edited by deutscheafrikar : 15th March 2010 at 23:59.
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Old 17th March 2010, 00:54   #51
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Ford TDCi is said for low end torque and lesser turbo lag. DDiSis for rush is higher rpm range. So is there any thing which is middle between these two things.

According to my 35k experience with Quadrajet and approx more than 10k with DDiS and some experience with TDCi. I can say Quadrajet is better in lowend as well as in high end. Tata has managed to get better torque at 1750 rpm and early turbo kick ensures that you will get good city driving experience as well as good highway experience.
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Old 17th March 2010, 01:09   #52
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Quote:
Originally Posted by sushantr5 View Post
Ford TDCi is said for low end torque and lesser turbo lag. DDiSis for rush is higher rpm range. So is there any thing which is middle between these two things.

According to my 35k experience with Quadrajet and approx more than 10k with DDiS and some experience with TDCi. I can say Quadrajet is better in lowend as well as in high end. Tata has managed to get better torque at 1750 rpm and early turbo kick ensures that you will get good city driving experience as well as good highway experience.
All the versions of Multijet engine have severe turbo lag, none of them is a match below 1800rpm to the Tdci engine in the Fiesta, Fusion and Figo.
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Old 18th March 2010, 20:05   #53
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@deutscheafrikar:Thanks at least I got one who understands the driveability problem of Vista TDI. I think I will have to adjust to the Harsh,High Noise of engine to get the sufficient torque.Somehow I cant stand the harshness of the engine at anything above 2200 rpm.But yes now I know that I have to live with it.You get what you pay for ,Rest on highways the car is a dream to drive,its only the damn ghats

@sushantr5: I totally agree with you one should purchase a car which is somewhat average in all the modes.Choosing a car superior in Top End gives problem at bottom end and viceversa.

Last edited by GTO : 19th March 2010 at 11:29. Reason: Hello, no need to type the entire post in italics. Corrected.
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Old 5th October 2012, 13:07   #54
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Re: TDCI or Multijet - Which is technically superior?

Essentially, the MJD is a more advanced Common Rail engine than the TDCI which is an older design Common Rail engine. The lag problem in the MJD has been sort of cured with the new Swift. I'm able to get decent response anywhere above 1500 rpm with the rush coming in above 2000. This was not the case with the old Swift which I used for a year as well.

The main advantage of the MJD is that it is more modern, and is being further improved. This is why Fiat is branding some of their European cars as Multijet II. As the technology improves, I feel the MJD will be as lag-fee or lag-less as the TDCI. Please also note that the TDCI is not being further developed, Ford has a new engine family for its European models (the same in the failed New Fiesta).

Finally, the solution to all this turbo lag is a two stage turbo or twin turbos that cover the entire revv range. BMW's new Petrol in the 328i has max torque from 1250rpm to 4800rpm which is an insanely large range. Future diesels will probably also benefit with lower rpms for their max torque figures.
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Old 5th October 2012, 15:26   #55
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Re: TDCI or Multijet - Which is technically superior?

I do not think there is much difference except in the nomenclature. Any Direct Injection engine tends to be noisy. It was FIAT who developed the technology of pre-injecting a very small (about 1mm cube) of fuel to start the combustion and dissipate/reduce the sharp sound. Then there were multiple (up to 5) injections (obviously at very high pressure) to get a smooth combustion throughout the stroke.

Each manufacturer has its own name for this - cRDi, eRDi, TDCI, and so on. Essentially the are very similar.

Turbo lag etc are functions of the Turbo design. For example a twin-turbo will have less lag that a single turbo, irrespective of the type of engine. So this is irrelevant to this discussion.
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Old 5th October 2012, 15:44   #56
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Re: TDCI or Multijet - Which is technically superior?

Both are Common Rail, but MultiJet is always better than the TDCi. The MultiJet has timing durations for fuel injections and this is heavily monitored based on all the engine sensors. In most of the ECUs major parameters are RPM, Speed, Temperature, Load, Pressure etc. In Multijet, the decision of fuel injection is made based on the parameter conditions and it can be for a long or short duration or at multiple times during POWER stroke. This varies at vehicle speeds and engine RPMs.

Last edited by yogeshnaik : 5th October 2012 at 15:47.
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Old 9th October 2012, 17:13   #57
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Re: TDCI or Multijet - Which is technically superior?

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Originally Posted by carmayogi View Post
Essentially, the MJD is a more advanced Common Rail engine than the TDCI which is an older design Common Rail engine.

The main advantage of the MJD is that it is more modern, and is being further improved.
Quote:
Originally Posted by yogeshnaik View Post
Both are Common Rail, but MultiJet is always better than the TDCi. The MultiJet has timing durations for fuel injections and this is heavily monitored based on all the engine sensors.


A question out of curiosity: Does the TDCI has the property of requiring maintenance or repair if it is not being subjected to adequate running or is kept idle for say- a month or two? Will this engine require frequent maintenance if it is run for only 10 kms a day? Is it good for a long term ownership (10 yrs) without adequate running?
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Old 11th October 2012, 01:53   #58
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Re: TDCI or Multijet - Which is technically superior?

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Originally Posted by vroom01 View Post
A question out of curiosity: Does the TDCI has the property of requiring maintenance or repair if it is not being subjected to adequate running or is kept idle for say- a month or two?
Ford diesels are extremely reliable, expensive though they are, as and when maintenance arises. If proper caution is exercised while driving (read mechanical empathy thread), the car is bound to give you trouble free service life.
On the other hand, while Ford will soon phase out this engine, affecting spares availability, Fiat engine spares would be easily available for a longer service life.
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Old 11th October 2012, 15:32   #59
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Re: TDCI or Multijet - Which is technically superior?

The performance of my Linea's MJD has been downhill past 50k, and had minor overhaul at 60k. Inspite of all this, the engine feels strained and is much more noiser now at high revs. Maybe mine was a one-off case, but I have heard of similar cases from Maruti and TATA dealers.

I must say that I had better expectations from India's National engine. But if the question is simply about technological superiority, I'd say that both MJD and TDCi are at par. Reliability and performance is a different matter altogether.
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Old 11th October 2012, 20:49   #60
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Re: TDCI or Multijet - Which is technically superior?

I would say that there are a whole lot of differences between the two diesel engines & most of them relate to the underlying design philosophy or the construction.

The most striking feature of the TDCi is its focus on being an energy-conserving design & that's why it uses a super-light aluminium alloy construction that has cast-iron webs embedded in between for optimal strength. The MJD also uses an aluminium alloy but its much heavier at about 125 kgs. [The MJD in the Maruti twins is a cast iron block & not aluminium, as per Fiat Cafe's manager]

The second most striking difference is in the valve-train of the two engine designs. The TDCi is an 8v SOHC design that uses a hollow crankshaft with pressed lobes & the valves are operated using hydraulic tappets with blade-type followers/rockers. The MJD on the other hand is a 16v DOHC that uses a much different setup.

The third most striking feature is the presence of siamese cylinders in the TDCi while the MJD has non-siamese cylinders.

And finally, the common-rail system is different between the two engines. The essential fundamental is the same but the two versions are still very different. Also, the famed Multijet (MJD I) can have upto 5 injections per stroke, while the TDCi can have upto 3 (if I remember correctly).
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