[extreme_torque]

Originally Posted by sreenivass

It should not be compared with petrol vehicles since both torque and BHP come relatively at higher revs in petrol engines. BTW I posted my observations about 5th gear speeds and revs in another thread. Petra 1.6L has a reasonably good pull from 1300 rpm onwards without load.

Swift VDi torque is supposedly at peak at 2000 rpm. so one expects good pull at 1500 RPM.

Agreed but your petra has a 1600cc engine and you are saying it pulls well 1300rpm onwards without load. Swift had i think 3-4 people on board that time.... and remember it a "small" diesel engine.

[sreenivass]

Originally Posted by extreme_torque

Agreed but your petra has a 1600cc engine and you are saying it pulls well 1300rpm onwards without load. Swift had i think 3-4 people on board that time.... and remember it a "small" diesel engine.

Thats where it is not a fair comparison. Swift diesel has peak torque 190Nm@2000 RPM, in fact higher than Petra's 137 Nm@4750 RPM, 100PS@5500 RPM. For Baleno 94BHP@6000 RPM and 132Nm@3000 RPM.

As a general rule diesel is supposed to give you better pull at low RPMs.

Now don't we expect better pull in swift than Petra, Palio, Baleno or any other Petrol engine.

When I said unloaded on Petra I was talking about two people.

[Vid6639]

There will be many factors affecting this. The gearing will be different. Sreenivass, have you driven the swift D?

I am sure once you drive it you will come to know the pulling power is more than the petra at lower rpm.

I drove the car and found the torque to be very good. I tried 3rd gear in crawling traffic and the car pulled with 3 people on board.

The Verna had turbolag and could not do the same.

The Petra is a petrol car and the power delivery will feel more linear. Diesel cars are different.

[sreenivass]

Originally Posted by vid6639

There will be many factors affecting this. The gearing will be different. Sreenivass, have you driven the swift D?

I am sure once you drive it you will come to know the pulling power is more than the petra at lower rpm.

I drove the car and found the torque to be very good. I tried 3rd gear in crawling traffic and the car pulled with 3 people on board.

The Verna had turbolag and could not do the same.

The Petra is a petrol car and the power delivery will feel more linear. Diesel cars are different.

Vid I have not driven a swift Vdi yet, but driven a few diesel cars. My comments are in response to the observations made by fellow BHPians. None of my friends own a VDi yet, hopefully some one will and I get to drive it.

[shuvc]

What I did like about the engine was the free revving nature. The tacho almost behaves like a petrol car. The sound of the engine is frankly no different to a petrol engine - maybe I felt more so, since the Baleno is somewhat buzzy beyond 4k.
As @1100D has already mentioned, while driving it, I kept wondering - if this is the 1.3, the 1.9 JTD will ROCK !! And if they add a VGT maybe ......

Fiat Linea - where art thou !!??

[vishnugs]

Figures taken from ACI, Feb 2007

===========0-100 == 20-80 (3rd G) ===40-100 (4th G)=================
Swift DDSi ----13.87----11.96----------- 14.14 ---------(Multijet CRDi)
City VTEC ----10.66----12.71------------17.29 ---------(Petrols)
Swift Petrol ---12.29----15.82------------21.88
Petra 1.6L ----11.57-----12.70------------19.70
Verna CRDi ---11.35----12.34 ------------16.35 ---------(CRDi)
Ford Fiesta----17.48----12.78------------16.70
Innova D4D---17.50----14.39-------------19.50
Octavia TDi---13.49-----12.9-------------25.3-----------(Volkswagen Proprietary DI)
Palio 1.9D-----23.79----14.70------------20.10----------(Traditional Diesels)
Indica---------22.39----18.0-------------29.70

So 0-100 figures show how the car will perform in a drag race but then the 20-80 and 40-100 figures show how the car will perform in highway practical catchup/overtakes. Its highly unlikely that some one will do 100 in the second gear on their cars for overtaking Swift DDSi, if they do they would ruin their fuel efficieny along with straining the engine.

[DCEite]

So Swift beats Octavia TDi in in gear performance. Good. 40-100 of Swift in 14.xx seconds is just amazing.

[jango]

Originally Posted by vishnugs

Figures taken from ACI, Feb 2007

===========0-100 == 20-80 (3rd G) ===40-100 (4th G)=================
Swift DDSi ----13.87----11.96----------- 14.14 ---------(Multijet CRDi)
City VTEC ----10.66----12.71------------17.29 ---------(Petrols)
Swift Petrol ---12.29----15.82------------21.88
Petra 1.6L ----11.57-----12.70------------19.70
Verna CRDi ---11.35----12.34 ------------16.35 ---------(CRDi)
Ford Fiesta----17.48----12.78------------16.70
Innova D4D---17.50----14.39-------------19.50
Octavia TDi---13.49-----12.9-------------25.3-----------(Volkswagen Proprietary DI)
Palio 1.9D-----23.79----14.70------------20.10----------(Traditional Diesels)

Indica---------22.39----18.0-------------29.70

So 0-100 figures show how the car will perform in a drag race but then the 20-80 and 40-100 figures show how the car will perform in highway practical catchup/overtakes. Its highly unlikely that some one will do 100 in the second gear on their cars for overtaking Swift DDSi, if they do they would ruin their fuel efficieny along with straining the engine.

These figures look intresting...Swift beating the Octavia

[DCEite]

Originally Posted by jango

These figures look intresting...Swift beating the Octavia

Well, i think it has something to do with power to weight ratio.. isnt it?

[vishnugs]

Thats true, in Swift DDSi you have a strong ingear pull which is justified by torque numbers.

Swift DDSi 1248 cc DOHC - 190 Nm @ 2000 RPM
Octavia TDI [SIZE=-1]1896 cc SOHC [/SIZE]- 210 Nm @ 1900 RPM

So this much torque for a small car can take it faster with "in gear" acceleration.

Source :
Eltdi HYUNDAI ELANTRA CRDi v SKODA OCTAVIA 1.9Tdi

[extreme_torque]

Originally Posted by sreenivass

Thats where it is not a fair comparison. Swift diesel has peak torque 190Nm@2000 RPM, in fact higher than Petra's 137 Nm@4750 RPM, 100PS@5500 RPM. For Baleno 94BHP@6000 RPM and 132Nm@3000 RPM.

As a general rule diesel is supposed to give you better pull at low RPMs.

Now don't we expect better pull in swift than Petra, Palio, Baleno or any other Petrol engine.

When I said unloaded on Petra I was talking about two people.

Correct, but in a petrol engine the peak torque might come in late but the power & torque are better spread throughout the rev range than a diesel.
I repeat again... asking a small diesel with a turbo to accelerate from 1500 revs in 5th gear with 4 people on board is tooo much. The car "will" accelerate or rather pull even in 5th but you will feel it 1800 revs onwards but asking it to perform at low revs, like it performs after the turbo hits is again too much.
Besides look at the evolution the diesel engines have gone through, here we have a small diesel, powering a car which isnt exactly light (1065 kgs) having flat out accleration comparable to a petrol car with in-gear acceleration decimating any car this side of 20 lakh rupees is a BIG achievment. The car is also almost as refined and as light and as responsive and as silent as a petrol, says a lot.

[sreenivass]

Originally Posted by extreme_torque

Correct, but in a petrol engine the peak torque might come in late but the power & torque are better spread throughout the rev range than a diesel.
I repeat again... asking a small diesel with a turbo to accelerate from 1500 revs in 5th gear with 4 people on board is tooo much. The car "will" accelerate or rather pull even in 5th but you will feel it 1800 revs onwards but asking it to perform at low revs, like it performs after the turbo hits is again too much.
Besides look at the evolution the diesel engines have gone through, here we have a small diesel, powering a car which isnt exactly light (1065 kgs) having flat out accleration comparable to a petrol car with in-gear acceleration decimating any car this side of 20 lakh rupees is a BIG achievment. The car is also almost as refined and as light and as responsive and as silent as a petrol, says a lot.

With due credit to 1.3 multijet, I do not mean Swift is a bad performer or unrefined. I am surprised that at 1500 RPM it can not give enough acceleration while peak torque of 190 Nm occurs at 2000 RPM.

As you said may be the torque curve changes the characteristic. Seems like the lack of turbo at low revs makes it feel like a different low power engine .

[Vid6639]

yes the turbo takes some time to spool up. it needs sufficient exhaust pressure before it can kick-in. This is called turbo-lag.

Secondly it may not have been 1500rpm maybe a little lesser. The tacho also will have an error. 500rpm is not a small difference. diesels power is available in a smaller power band. outside the band there is no pull.

The Verna suffers the same to a greater extent. there is nothing till around 200rpm and then sudden jerk forward. If you are with even 2 person you may find it poor acceleration.

And all this is relative. the person might be expecting something more and when test driving that did not happen it gives the feeling car is underpowered.

[sreenivass]

Originally Posted by vid6639

yes the turbo takes some time to spool up. it needs sufficient exhaust pressure before it can kick-in. This is called turbo-lag.

Secondly it may not have been 1500rpm maybe a little lesser. The tacho also will have an error. 500rpm is not a small difference. diesels power is available in a smaller power band. outside the band there is no pull.

The Verna suffers the same to a greater extent. there is nothing till around 200rpm and then sudden jerk forward. If you are with even 2 person you may find it poor acceleration.

And all this is relative. the person might be expecting something more and when test driving that did not happen it gives the feeling car is underpowered.

Which means there are still things to be achieved it making multijet/ CRDI closer to Petrols, one of them being flattening the torque curve and probably making power delivery more uniform.

[Vid6639]

yup sreenivass there is definitely scope for improvement. the refinement is definitely there to match the petrol.

I guess the diesel engine is difficult to achieve a linear power delivery since the control of the combustion is not the same. In case of petrol you have control of the ignition whereas in diesel that's not there.

There are several factors I guess but the advantages of diesel are definitely overtaking than owning a petrol car.