[audioholic]

Originally Posted by blacksport

Forgot all those K-series ads?

When it was launched along with the Kappa from hyundai, 85 odd horses for the 1.2l engine (Naturally aspirated ) was high. Same followed by the Honda I-Vtec. Now in case this revotron at least gave five horses more, it would have definitely been worth it. Driveabilty can be greatly altered by gearing. If that was their prime focus, as I told in the previous post, a good spread of ratios would have been a lot cheaper as an option than provide a turbo and related stuff. That's where decisions come to play.

[damodar]

Another view on the engine by Motoroids and seems close to what TATA wanted to deliver.

It must, however, be noted that the 1.2 Revotron engine, as mentioned earlier, is oriented towards driveability and efficiency and not outright performance. So if you’re looking for a turbo kick-in, or a sudden burst of power, you’d be disappointed as there is none. The engine is extremely linear with strong low to mid-range response. The performance tapers off towards the top end of the rev range.

The 1.2 Revotron engine delighted us with its silky smooth nature and terrific pulling capabilities in higher gears at low speeds. However, if you are looking at the Zest 1.2 powered by Revotron as a medium to quench your thirst for performance and power, then you are probably mistaken. Even with its 90 PS of power and 140 Nm of torque, the Zest’s petrol engine isn’t too keen to rev to the moon and back. This unit excels in delivering effortless, efficient and hassle free driving at everyday speeds, and that’s what it should be recognized and appreciated for. Look elsewhere if it’s sheer kicks you’re looking at.

[extreme_torque]

Originally Posted by humyum

Well, after getting bashed by so my people, I hope whatever I was saying all this while finally makes sense. Nothing drastic = Run of the mill. The hype will get a final coffin in the nail when people test drive the car. But on the other hand the Zest Diesel AMT looks like a fantastic raised to N proposition, if priced right ( which Tata always does ), they have a super selling product at hand.

Run of the mill is depending on what you read and what do you share here. From TopGear India

"a segment-first 1.2-litre Revotron turbo-charged petrol engine. Teamed with a 5 speed manual at the launch, all the 89bhp and 140Nm of torque will be sent to the front wheels. Another segment-first are the multi-drive modes that lets you choose from three settings - Eco, City and Sport – which can be accessed via click of a couple of buttons.

These modes do make a difference and come in quite handy in our driving conditions. And while we are still at it, the Zest will surprise you with its overall driving dynamics. Acceleration in Sport mode is sharp with turbo kicking in at around 1800rpm and pulling cleanly till 6000rpm. The gearbox too is butter smooth with short and precise throws teamed with well spaced out ratios to aid city and highway driving."

[Captain Slow]

Read this review at overdrive

http://overdrive.in/reviews/2014-tat...dia-road-test/


Tata seems to have gone the extra mile in keeping the noise levels low as possible.

To keep NVH levels in cabin comfortable there are three sound deadening layers. There is an absorptive layer inside the engine bay, followed by a reflective layer inside the cabin on the firewall. This is the wall separating the engine bay from the cabin. And finally there is another absorptive layer over the reflective one. So is the cabin a quiet place? The petrol definitely is but the diesel is also surprisingly quiet if driven calmly.

The Rear suspension says
Semi-independent; twist beam with coil spring and shock absorber

How is this different from a regular Torsion beam suspension?

[DerAlte]

Originally Posted by Captain Slow

Read this review at overdrive ...

...

Wonder what is this 'reflective layer' *inside* the cabin. What is it "reflecting"? If it is "reflective", wouldn't one expect it to be on the engine bay side of the firewall? Creative writing!

[humyum]

Originally Posted by extreme_torque

Run of the mill is depending on what you read and what do you share here. From TopGear India

"a segment-first 1.2-litre Revotron turbo-charged petrol engine. Teamed with a 5 speed manual at the launch, all the 89bhp and 140Nm of torque will be sent to the front wheels. Another segment-first are the multi-drive modes that lets you choose from three settings - Eco, City and Sport – which can be accessed via click of a couple of buttons.

These modes do make a difference and come in quite handy in our driving conditions. And while we are still at it, the Zest will surprise you with its overall driving dynamics. Acceleration in Sport mode is sharp with turbo kicking in at around 1800rpm and pulling cleanly till 6000rpm. The gearbox too is butter smooth with short and precise throws teamed with well spaced out ratios to aid city and highway driving."

https://www.youtube.com/watch?v=sl9zcOwTOpU

I hope this clears EVERYTHING.

[damodar]

This engine comes with a water cooled turbo charger which very few cars like linea T-Jet have. Does the Polo TSI and Ecosport come with a water cooled turbo charger?
Also the primary focus of this engine seems to be the daily commuter who encounters frequent start stop situations, so having a water cooled turbo will allow the engine to be shut down without the 2 minute idling.

[amitk26]

Originally Posted by DerAlte

Wonder what is this 'reflective layer' *inside* the cabin. What is it "reflecting"? If it is "reflective", wouldn't one expect it to be on the engine bay side of the firewall? Creative writing!

Ha ha ha .
How on earth these people who even do not understand difference between reflection and absorption feel confident enough to talk about slightly more complicated concepts such as power / torque curves , gear ratios etc.

This is not the only incidence many times after reading such nonsense I wonder if these auto journalists have even studied any basic high school level science or not.

[sgiitk]

Tuners like Pete will have a field day.

[anandpadhye]

Originally Posted by damodar

This engine comes with a water cooled turbo charger which very few cars like linea T-Jet have. Does the Polo TSI and Ecosport come with a water cooled turbo charger?
Also the primary focus of this engine seems to be the daily commuter who encounters frequent start stop situations, so having a water cooled turbo will allow the engine to be shut down without the 2 minute idling.

Interesting. I will like to check if my TSi has water cooled turbo. Any clue how to check that? And when they say "water cooled", they actually mean "coolant cooled" right? In any case, the water/coolant pump is run by the engine belt no? Then how can it continue to run after engine is shut off?

[Captain Slow]

Originally Posted by anandpadhye

Interesting. I will like to check if my TSi has water cooled turbo. Any clue how to check that? And when they say "water cooled", they actually mean "coolant cooled" right? In any case, the water/coolant pump is run by the engine belt no? Then how can it continue to run after engine is shut off?

Originally Posted by damodar

This engine comes with a water cooled turbo charger which very few cars like linea T-Jet have. Does the Polo TSI and Ecosport come with a water cooled turbo charger?
Also the primary focus of this engine seems to be the daily commuter who encounters frequent start stop situations, so having a water cooled turbo will allow the engine to be shut down without the 2 minute idling.

I guess the TSI, ECO sport, MJD are all oil cooled turbos.?

A bit of searching revealed the following

Oil cooled housings use the oil flowing through it to lubricate the bearing section and also to carry some heat away from the center housing.
Water cooled housings have a separate cavity which you run a coolant feed and coolant drain line to just the same as the oil feed and oil drain lines. The engine coolant flowing through there carries away more heat from the center housing than the oil can.

Under long-term, hard running, the water cooled housings are usually perferred over oil cooled housings.

[anandpadhye]

Originally Posted by Captain Slow

I guess the TSI, ECO sport, MJD are all oil cooled turbos.?

A bit of searching revealed the following

Interesting discussion about TSi turbo:
http://www.briskoda.net/forums/topic...-cooled-turbo/

[sandeepmohan]

Originally Posted by anandpadhye

Any clue how to check that? And when they say "water cooled", they actually mean "coolant cooled" right? In any case, the water/coolant pump is run by the engine belt no? Then how can it continue to run after engine is shut off?

Yes; coolant cooled.

Look for a coolant pipe running out of the expansion tank to the turbo. Thats how it is on my T Jet. They've put a T joint on the coolant pipe running to the engine and directed coolant to the turbocharger. I have not really looked for the return pipe though. Coolant can't go in and just stay there, it has to return in to the cooling system.

Water cooling is provided as a secondary way for cooling the turbocharger. Engine oil is very much circulated in the turbo charger and it is best to practice engine idle for atleast half a minute before shut down.

The life of the turbo is down to quality of engine oil too.

I idle the engine based on situation. I live in a small apartment. The guard is either taking a nap or is not around. The apartment gate is kept closed too. From the time I stop my car to get down (not engine shut down), open the gate, drive at idle speed into the apartment block and into my parking slot, its usually well over half a minute. More than sufficient for a spool down of the turbo. Besides; the last bit of the run to my house is slow so this keeps things in check.

[im_srini]

Originally Posted by sandeepmohan

Look for a coolant pipe running out of the expansion tank to the turbo.
Thats how it is on my T Jet.
They've put a T joint on the coolant pipe running to the engine and directed coolant to the turbocharger.
I have not really looked for the return pipe though.
Coolant can't go in and just stay there, it has to return in to the cooling system.

Hi Sandeep,
From my limited understanding of coolant systems:
If it's just a T-Connector off of the line to the expansion-tank, it's unlikely to have a return line.
That line is unpressurized & basically means the bearnings are simply bathed in coolant.
Unlike the main coolant circuit ( water-jacket, thermostat, water-pump, & radiator ), there's also no guarantee ( requirement ) that this line ( radiator-cap to expansion-tank ) will always contain coolant.

[sandeepmohan]

Originally Posted by im_srini

If it's just a T-Connector off of the line to the expansion-tank, it's unlikely to have a return line.
That line is unpressurized & basically means the bearnings are simply bathed in coolant.radiator-cap to expansion-tank ) will always contain coolant.

Its more a T Joint off the main line that runs to the engine from the expansion tank.

Take a look at the last image to understand the arrangement.
http://www.team-bhp.com/forum/test-d...ml#post2616456

I'll have to research a bit if its a case of the bearings soaked in coolant. I've not heard of such implementation.

In case of the T Jet engine, there is no radiator cap. There is only a expansion tank.

What you say can be true.