[4x4addict]

@directinjection has highlighted a good point that very few people are aware of. The 2.0 Liter Tata Estate/Safari/Sumo/207 etc engine was heavily inspired by Peugeot and not Mercedes.

Many years back, I happened to read a road test of the Tata Gurkha in UK (Export version of Tata Sierra 4x4) and they had a write up on the engine.

[Aroy]

Interesting. I had read some where quite some time ago that both the 2.2L engines - Tata and Mahindra were designed by AVL. Each manufacturer added their own extras - turbo, common rail etc.
Mahindra
Scorpio Vehicle Evolution | Mahindra Automobile | Mid Size Vehicle | Mahindra India
Tata
In their report they have itemized collaboration with AVL (page 27)
http://www.google.co.in/url?sa=t&rct...hHcMASPREN4rpg
FULL THROTTLE: Tata Safari 2.2
Details Of Tata Motors 2.2L VTT DICOR Engine | MotorBeam - Indian Car Bike News & Reviews

[jess]

The Engine we missed here from the TATA stable was the 3.0L DiCOR.
This engine is based on the 497-SP and had a brief stint in the safari 2006 just before the 2.2L DiCOR.
It is a Common Rail Engine without a DOHC but the same Push rod based system which is on the Sumo Victa.
Its still being used in some models of the Xenon.

& SP stands for Square Pattern.

[4x4addict]

Originally Posted by jess

The Engine we missed here from the TATA stable was the 3.0L DiCOR.

@jess, is it the same crde 3.0 CR4 engine doing duty in the latest Sumo Gold?

[jess]

The 3.0L DiCOR was developed for 2006 Safari conditions. It was a BS2/3.
That same engine is now being used on the XENON 3.0L Model.
You cant get a 3.0L Xenon BS4 model.
However, The 3.0L CR4 uses the same block but it is developed as a BS4. The BS3 Sumo Gold has the same block and it is not a Crde.
3.0L CR4 is a strip down engine and produces less power compared to the 3.0L Dicor BS3.

[directinjection]

Originally Posted by sridhar-v

@directinjection
I was mentioning only engines currently in service. But nice to know the history of the 679 family.(that is how I should have designated it!!)

The engine is called 697, not 679. You had used the correct designation earlier. The designation follows the usual Tata pattern: the first digit indicating the number of cylinders and the next digits the bore size in MM.
697 is license-built OM 352 but with various Merc-independent modifications done from time to time.

[Sutripta]

Question for the gurus:
If given two engines side by side, but without any other information, how will we determine if the engines are 'related' to each other?

Regards
Sutripta

[directinjection]

Originally Posted by Sutripta

Question for the gurus:
If given two engines side by side, but without any other information, how will we determine if the engines are 'related' to each other?

Regards
Sutripta

The physical shape, dimensions, design, etc. of the engines would be one among many factors to be considered in deciding if the two engines are related. Establishing "relationship" would be easier where the engines share the same block. For instance, if you compare OM 312 with OM 352, Tata 692, 695, 697, you'll notice a lot of physical similarity, all engines sharing the same block. If you can disassemble the engines, you can also compare the internal components. Other things to be looked at would be (a) engine sound along with NVH levels, (b) fuel type (you can have petrol and diesel versions based on the same block viz. Tata Indica 1405/1396 CC block, Ambassador 1489 CC unit) (c) fuel and oil consumption, etc. (d) BHP & torque figures along the RPM band, (e) sub-assemblies, (f) smoke and other emissions.

Two engines may look identical and yet have huge differences in power and performance characteristics. The Cummins "B" series 5.9 litre engine is available in various configurations starting from naturally aspirated 120 HP version (not sure if it is still available), 145 HP turbo version, 160/180/230 HP TCIC version. A 230 HP CNG version too is available.

497 SP engine used to develop 65 HP in Tata 407 in NA form whereas its CRDI version as used in Safari Dicor developed 115 HP.

How one wishes auto reviewers also reviewed and compared the engines thoroughly and not stopped at telling us how they feel or behave!

[Sutripta]

Originally Posted by directinjection

If you can disassemble the engines, you can also compare the internal components.

Hi,
Should have made it clear. Of course you can disassemble the engine, take any measurements you want, etc.

Was not talking of engines from the same manufacturer.

Think that you are conducting a paternity test, an engine paternity test! e.g. as mentioned in this thread, how would you go about determining whether Tatas 2 ltr Sumo engine was Peugot derived, or Mercedes derived? Or how would you go about finding the truth of 'the mHawk 2.2 and the Dicor 2.2 are essentially the same engine'. When you know nothing of AVL. All you have are the two engines in front of you.

Regards
Sutripta

[sridhar-v]

@ directinjection - my typo error. Shows that I need a long driving vacation - just pooped from overwork & stress.

For the queries re how u differentiate the engines ( the 2.2 Dicor & M-Hawk). Basically all engine designs are over 100 years old. The basics has not changed- its a piston & crank & cam arrangement. So you look at overall construction of the blocks, heads, crankshaft & camshaft.
I have seen the blocks of both the TML 2.2 Dicor & M&M M-Hawk. The camshaft position is different & so is the basic shape of the end flanges(water pump side & flywheel side). I will try & see if I can retrieve the old drgs so that I can tell u all if the cylinder pitch is the same or not. Give me some time for that.

[directinjection]

Originally Posted by Sutripta

Hi,
Should have made it clear. Of course you can disassemble the engine, take any measurements you want, etc. Was not talking of engines from the same manufacturer.

Whether the two engines being compared belong to the same manufacturer or not is immaterial. You can compare any two engines using the various yardsticks I had mentioned. A detailed technical comparison would require a proper lab and equipment.

Originally Posted by Sutripta

Think that you are conducting a paternity test, an engine paternity test! e.g. as mentioned in this thread, how would you go about determining whether Tatas 2 ltr Sumo engine was Peugot derived, or Mercedes derived?

By comparing the Tata engine with the Merc or Peugeot one, factor by factor. You could begin by comparing their technical literatures if available. They contain a wealth of information including technical specs, drawings, photographs, etc. If that does not suffice, you'll need the two (or more) engines in physical form and compare them. If you still have doubts, you'll have to subject them to proper laboratory testing.

Originally Posted by Sutripta

Or how would you go about finding the truth of 'the mHawk 2.2 and the Dicor 2.2 are essentially the same engine'. When you know nothing of AVL. All you have are the two engines in front of you.

If the two engines are in front of you, the physical appearance, shape, configuration, sub-assemblies, etc. would throw some light on the subject. However, you'll still require their technical specs in writing since calculating them on your own would take you ages. Finally, for a proper foolproof comparison, you'll need to do lab-testing. Instead of doing all this yourself, you can also read the comments of someone who has done such a comparison and analysis.

It's a lot easier to compare vehicles than their engines. That's why you usually don't come across engine reviews.

Originally Posted by sridhar-v

For the queries re how u differentiate the engines ( the 2.2 Dicor & M-Hawk). Basically all engine designs are over 100 years old. The basics has not changed- its a piston & crank & cam arrangement. So you look at overall construction of the blocks, heads, crankshaft & camshaft.

Well said! Like the engines, the basic design of all vehicles is also the same, yet they do differ from one another in terms of appearance, specs and performance. Heck, the same thing applies to humans too!

Originally Posted by sridhar-v

I have seen the blocks of both the TML 2.2 Dicor & M&M M-Hawk. The camshaft position is different & so is the basic shape of the end flanges(water pump side & flywheel side). I will try & see if I can retrieve the old drgs so that I can tell u all if the cylinder pitch is the same or not. Give me some time for that.

Please take your time sir! We look forward to your views since you have valuable first hand experience. I had read that the bore and stroke figures of the two engines are also different although both displace 2179 CC which is also the displacement of an old Peugeot engine, causing some people to comment that the 2.2 Dicor is a Peugeot derivative.

[Sutripta]

Originally Posted by sridhar-v

For the queries re how u differentiate the engines ( the 2.2 Dicor & M-Hawk). Basically all engine designs are over 100 years old. The basics has not changed- its a piston & crank & cam arrangement. So you look at overall construction of the blocks, heads, crankshaft & camshaft.
I think everyone on TBhp knows the basics of a (conventional) engine.

I have seen the blocks of both the TML 2.2 Dicor & M&M M-Hawk. The camshaft position is different & so is the basic shape of the end flanges(water pump side & flywheel side). I will try & see if I can retrieve the old drgs so that I can tell u all if the cylinder pitch is the same or not. Give me some time for that.

Aren't both DOHCs?
Much is made of distance between bore centres. But I think it is more of a manufacturing issue (when you have tooled up for mass manufacture) than a design issue. At least for the block. (Crank is a different matter. with the shift of bearing positions, both main and bigend, and a slightly different length, its vibrational modes, nodes etc will have to be recalculated, and validated.)

Originally Posted by directinjection

Whether the two engines being compared belong to the same manufacturer or not is immaterial. You can compare any two engines using the various yardsticks I had mentioned.
A recap please.
A detailed technical comparison would require a proper lab and equipment.
No bar on lab use. What exactly should the lab measure?

By comparing the Tata engine with the Merc or Peugeot one, factor by factor.
A listing of the factors would be educative.

You could begin by comparing their technical literatures if available. They contain a wealth of information including technical specs, drawings, photographs, etc.
As I said, if we only have the engines with us. To do as we please with those. Nothing else.
If that does not suffice, you'll need the two (or more) engines in physical form and compare them.
What exactly do we compare? How do we interpret the results?
If you still have doubts, you'll have to subject them to proper laboratory testing.
What exactly do we ask the labs to measure/ test?



If the two engines are in front of you, the physical appearance, shape, configuration, sub-assemblies, etc. would throw some light on the subject.

However, you'll still require their technical specs in writing since calculating them on your own would take you ages.
This is a theoretical exercise. Don't worry about the time.
Finally, for a proper foolproof comparison, you'll need to do lab-testing.
Once again. test/ measure what?

Instead of doing all this yourself, you can also read the comments of someone who has done such a comparison and analysis.
And how did they do it. I mean if they were not part of the design team, or had inside information.

It's a lot easier to compare vehicles than their engines. That's why you usually don't come across engine reviews.
Well, one does have engine of the year awards. Wards.

So ultimately where do we stand on the Peugot/ MB issue, and the mHawk/ Dicor issue?

Regards
Sutripta

[lifebuoy]

Some inputs on the hawk's components :
More power for the Mahindra Scorpio

[Sutripta]

^^^
Hi,
Missing something. That link is devoid of practically any information. And seems quite old. Is there another link somewhere?

Regards
Sutripta

[autocrat]

From my days in MICO (now Bosch), I have seen several engines being developed in collaboration with third party consultants.

Its quite easy for the engine manufacturers to design and fire an engine, but the real problem is fine tuning the performance and emission characteristics.

This is where consultants like AVL come into picture, and they recommend finer design details like the piston bowl design, injector positioning, spray cone angle, nozzle length, number of holes on the injector, injection durations, number of injections, timing etc.

they do have "template solutions", but each engine design is fine tuned as per the specifications the engine is required to meet.

Just by sharing the block / bore:stroke, we can not conclude that the engines are same. There is more to engines than what meets the eye.

Its indeed true that TATA engines were inspired by Peugeot. I was once told by a gentleman who worked on the Indica project that the Indica engine too was based on a Peugeot one.