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Old 7th March 2010, 18:29   #31
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There is one more may be small difference....
MultiJet had a timing belt which is a chain system and TDCi has a normal old timing belt...
As a result the maintenance is very low on MultiJet which cost a lot in TDCi (though I am not sure about the cost.)
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Old 7th March 2010, 18:56   #32
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Originally Posted by .anshuman View Post
Multijet = BOSCH
TDCi = Delphi ...
Are you sure? I though Multijet = Magneti Marelli (a FIAT company)?

If it were to be BOSCH, it should have been CRDI - which is a BOSCH patented name, I guess.

Multijet somehow sounds odd - are there 2 injectors per cylinder or something?
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Old 7th March 2010, 22:50   #33
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Originally Posted by DerAlte View Post
Multijet somehow sounds odd - are there 2 injectors per cylinder or something?
The TATA/Fiat's implementations have 4, hence the name Quadrajet (I guess)
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Old 7th March 2010, 23:21   #34
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MultiJet is a trade mark owned by FIAT... Magneti Marelli is principle suppiler of a lof of coponents to FIAT, including ECU, Wire harness, emission systems etc....

Quote:
Originally Posted by DerAlte View Post
Are you sure? I though Multijet = Magneti Marelli (a FIAT company)?

If it were to be BOSCH, it should have been CRDI - which is a BOSCH patented name, I guess.

Multijet somehow sounds odd - are there 2 injectors per cylinder or something?
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Old 7th March 2010, 23:36   #35
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Originally Posted by rajat60 View Post
MultiJet is a trade mark owned by FIAT ...
So is Magnetti Marelli!

In the current sense, the engine takes on the injection system's brand name, a la Hyundai (CRDI), Ford (TDCi), Toyota (D-4D), etc.
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Old 8th March 2010, 12:23   #36
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Originally Posted by rajat60 View Post
Just to add my 2 cents, the main difference is in the name itself. MultiJet can split one fuel delivery into 5 small burst... which leads to a linear power delivery, lower emission and better efficiency. MultiJet Gen II this has been upped to 8 burst per power cycle.

The whole aim of Multijet technology was to achieve better fuel efficiency. The operating range of the engine where it is most efficient is easily attainable by using multijet. Better efficiency does not mean more POWER. So the engine will not be as responsive as TDCi i.e. why the turbo lag. For city commutes TDCi will be better if someone wants a race at every traffic light. Multijet is for the people who like to do things which are more subtle and without gulping too much fuel.
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Old 8th March 2010, 13:15   #37
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Which one gives better mileage. I mean FE?
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Old 8th March 2010, 13:24   #38
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Default Multijet-MJD

Multijet was born as an outcome of war between PD (Pump Deuse) technology of VW, Common rail Technology of Delphi and of Fiat/Bosch.
Pump Deuse Technology initially surged ahead with good Throttle response but ultimately failed in long run as it was not able to cope up with the emission requirements.
Delphi used solenoids to move the needle valve in the injector and were able to achieve two squirts per cycle. But ultimately could not succeed due to the high inertia of the solenoid and could not go further than two squirts per cycle.
Fiat/Bosch used quartz wafers (same as used in our quartz watches) to move the needle valve in injectors.Advantage was low inertia of quartz wafers and fast response to input signal. This led to 3 squirts then 4 squirts per cycle.It achieved both the emission standards and also the low NVH for the diesel engine.
I have not driven TDCI but would prefer a TDCI for the reason that it has very less Turbo lag. Turbo lag can be quiet annoying while climbing hills especially when you have a slow moving car in front of you and you cannot keep the engine rpm near/above 2000rpm.-Big problem with TATA TDI engines-Once the rpm goes below 1500 rpm you are doomed, you are left with nearly no torque at hand and it takes ages for the vehicle to respond as per the trottle movements. I know TDI is non CRDI but I think one will face the same situation with a Multijet on steep inclines where you cannot maintain a required speed of the car.(Although Multijet will be far better than TDI).
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Old 8th March 2010, 14:03   #39
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Quote:
Originally Posted by DerAlte View Post
Multijet somehow sounds odd - are there 2 injectors per cylinder or something?
It's not the number of injectors, rather it's the number of injections.
(Source : Fiat.co.uk | Multijet Diesel Engine. The next-generation diesel engine from Fiat Fiat.co.uk)

Also, below is some information regarding the TDCi from Ford.
(Source : FORD DURATORQ TDCi: A NEW GENERATION OF DIESEL ENGINE | Ford Motor Company Newsroom)

Quoted from the article : "In addition, Ford's innovative transient overtorque technology generates an additional low-speed torque that contributes to Duratorq TDCi's mid-range flexibility and instant responsiveness. Transient overtorque technology uses sophisticated matching between the turbo boost, injection quantity and timing to push up the torque curve in the low rev range and thereby overcome the lag inherent in steady-state turbodiesel operation."

Hope this clarifies some queries.

Quote:
Originally Posted by amit_purohit20 View Post
Turbo lag can be quiet annoying while climbing hills especially when you have a slow moving car in front of you and you cannot keep the engine rpm near/above 2000rpm.-Big problem with TATA TDI engines-Once the rpm goes below 1500 rpm you are doomed, you are left with nearly no torque at hand and it takes ages for the vehicle to respond as per the trottle movements. I know TDI is non CRDI but I think one will face the same situation with a Multijet on steep inclines where you cannot maintain a required speed of the car.(Although Multijet will be far better than TDI).
I did not get the point here. When you are climbing a hill, you usually downshift and keep the engine rpm in it's powerband. Atleast this is what I do when travelling through the Ghat sections which I usually do once every two months and never faced any problems. Even on a petrol engine, you don't try to climb a hill in 3rd gear and let the rpm fall below a limit.

Last edited by A350XWB : 8th March 2010 at 14:12.
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Old 8th March 2010, 14:43   #40
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Quote:
Originally Posted by amit_purohit20 View Post
Multijet was born as an outcome of war between PD (Pump Deuse) technology of VW, Common rail Technology of Delphi and of Fiat/Bosch.
Pump Deuse Technology initially surged ahead ...
Delphi used solenoids to move the needle valve... could not go further than two squirts per cycle. ...
Not sure if that was the genesis of Multijet, but definitely it was no war between Pumpe-Düse and Common Rail (which incidentally came out of Bosch first, and not Delphi; in fact FIAT was the first in the world with CR - about 70-80 years back, but could not come up with a commercially viable and stable system).

2 separate things are being mixed up here:
1. Between Pumpe-Düse and Common Rail the issue was of consistent pressure at the inlet of the injector, for efficient injection profile. Pumpe-Düse could only reach a short peak based on the cam driving it, suffered injection timing inconsistency w.r.t. engine RPM (how much can one optimize a cam?) and hence has FE issues. But it has always been a good viable system, better than electronically controlled in-line and distributor pumps for car engines. CR pressure was independent of engine RPM, and hence the injection is much more controlled - the basis for efficient injection control for FE and emission control

2. Solenoids (even Bosch used them till 10 years back) do have a limitation - because, quite simply, inductive elements have limitations in high frequency (or sharp rise and fall) behavior. Quartz actuators do not suffer that limitation. But, this is not the limitation of the type of injection system, whether Pumpe-Düse, CRDI or electronically controlled in-line and distributor pumps. Just that these injectors are far better at producing multiple short bursts in the injection profile for every firing

Yes, the real issue is number of short bursts per firing, and it takes *years* of testing in the lab to get it right. Diesel injection has a long way to go, unlike petrol injection which seems to have reached a plateau (not many companies pursuing Direct Petrol Injection, for example).

Last edited by DerAlte : 8th March 2010 at 14:51.
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Old 8th March 2010, 14:44   #41
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Most of the posts in this thread list only the various technical specifications of both. I don't think as an end user, it is possible to say which is technically superior.

We can only list the pros and cons of both pertaining to various factors like FE, turbo lag, drive ability and the like.
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Old 8th March 2010, 19:27   #42
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Quote:
Originally Posted by autogeek View Post
Most of the posts in this thread list only the various technical specifications of both. I don't think as an end user, it is possible to say which is technically superior.

We can only list the pros and cons of both pertaining to various factors like FE, turbo lag, drive ability and the like.
Unfortunately you are right.

On such a small engine it is very difficult to have the best of both worlds. The 2 engines are aimed at different users.

To clear up the new Ford KA situation:

The Ford KA is built on the Panda platform, which is used for the 500 and the KA too. All three models are being built in Tichy in Poland by Fiat. The engines are shared with the 500 apart frrom the 1.4 16v, which might happen sometime soon. The 1.4 T-Jet might end up with the RS badge.

Drive train parts are identical too.
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Old 10th March 2010, 23:51   #43
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Default Vista TDI driveability issue

Quote:
I did not get the point here. When you are climbing a hill, you usually downshift and keep the engine rpm in it's powerband. Atleast this is what I do when travelling through the Ghat sections which I usually do once every two months and never faced any problems. Even on a petrol engine, you don't try to climb a hill in 3rd gear and let the rpm fall below a limit.
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.
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Old 12th March 2010, 23:27   #44
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Problem 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.
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Old 13th March 2010, 10:58   #45
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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"
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