Tata Indigo LS Diesel

[tsk1979]

Simple
Indigo RPM maxes out at 4500 or so. It has the same top speed as wagon R, so it will be achieved at lower RPM
Why does it max out at 4500? Coz its a diesel and the max torque is from 1800-3200RPM, so gearing is designed for that. If you had a car which had lots of power but ony 3000RPM max you would see the same speeds at even lower RPM

[Shan2nu]

Shantunu, i am not saying that wagonr/santro cannot attain more than 25+ etc. in first gear.. thats not the issue... what i wanted to emphasize that Indica reaches that speed at a lower engine RPM...

(correct me if i am wrong, as i am not too technical about car mechanics..)

Ok, the deal is that since a diesel engine usually produces it's peak power and torque at very low rpms, it's redlined at a much lower rpm than a petrol engine.

Now the Wagon R has to revv it's engine to 6800rpm in 1st and 2nd to hit those speeds i mentioned. Since the Wagon has a relatively higher revving engine, then gear ratios need to be short, to compensate for the lack of power and torque at low rpms.

Now, the indica diesel "i think" redlines at 4500 rpm. Which means that max power and torque are produced below that engine speed.

If i were to use the same ratios as that of the Wagon R in your Indica, you would have spent all your time concentrating on the gear shifts bcoz, the moment you redline in 1st and shift into 2nd, your engine speed would have already reached close to it's redline.

Ok, i'll make it simpler, now imagine i'm driving a Wagon R with a rev limit of 4500 rpm. So, the max speed i'd be able to hit would be :
30.1 kmph in 1st
54.38kmph in 2nd
80.4kmph in 3rd
112kmph in 4th
136kmph in 5th

Though these gear ratios would make the Wagon R peppy, whats actually happening is that your cruising rpm will suffer a lot, you'd be doing high rpms in 5th gear at 80-100kmph which will hamper your highway mileage, you won't be able to stay in one gear for long leading to a very irritating drive and i'f you've noticed, the top speed of the car has been reduced to 136kmph, where as the present Wagon R manages 145-150kmph.

In such cases you have 2 choices, you either recalculate your gear and final drive ratios or, (if you want a peppy car) add another 2 gears such that your car manages it's top speed of 145kmph without sacrificing the peppyness of the car.

If your Indica was to have 6-7 gears, it would have revved much faster to it's redline but, that would have reduced your max speed in each gear and your FE would have reduced.

So, what TATA has done is that they've calculated the ratios such that even though the car doesn't feel all that peppy, it'll still hit it's top speed within those 5 gears and due to the tall nature of the ratios, you can cruise at 100kmph in 5th at a low engine rpm which not only makes the car very fuel efficient but, also increases engine life.

Shan2nu

[hell_rider]

stratos.....

now that you have clocked some significant mileage on your indigo (which looks very well maintained & shiny by the way) can you tell us about

1. any increase in noise levels inside the cabin ;
2. increase of diesel clatter ;
3. any other pronounced noise causing wear and tear

will appreciate that information pal...

apart from that have you been exposed to any new likes / dislikes or good features/ irritants on the Indigo, now that you have been driving it for quite a while ?

thanks,

hell_rider

[Stratos]

Originally Posted by hell_rider

stratos.....

1. any increase in noise levels inside the cabin ;
2. increase of diesel clatter ;
3. any other pronounced noise causing wear and tear

Have replied a similar thing in another thread. After 11,000 kms on the clock noise, clatter has not increased at all. Absolutely nothing. The car is still as silent (even after being a diesel) as it was when brand new. All electricals working absolutely fine, except for the side indicator knob. Sometimes it doesnot go back to its original position after turning the car in the appropriate direction.

Things I have really liked about the car:

1: The seating position is very good and provides excellent all round view.

2: The steering wheel is very precise and light.

3: Overall ergonomics are very good.

4: A very good A/C system.

5: Lastly, Consistent Fuel Efficiency, space and comfort. In the its price, the Indigo is the biggest thing you can have.

[GTO]

5: Lastly, Consistent Fuel Efficiency, space and comfort. In the its price, the Indigo is the biggest thing you can have.

Absolutely agree. The pros of an Indigo by far outweigh the cons.

GTO

[hell_rider]

thanks stratos,

precisely the information i wanted. opinion of a owner of a indigo he has run for a while.

but i think i have a different take on the all -round view thing. I think the design of the dash kind of hampers the visibility. will take another test drive though. i need to have another go at the indigo.

ciao,
hell_rider