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Old 6th May 2010, 12:15   #1471
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Originally Posted by SPIKE ARRESTOR View Post
Yikes, i am attaching an excel sheet which will give you a brief summary of the tests that a manufacturer has to pass. These are vehicle level tests(read cutting onions), there are hundreds of component level tests also. Imagine getting all these done. Also, it is not necessary that your vehicle passes all these in one go. If one fails, you have to do several iterations. For e.g. if tires fail in some test, there are whole lot of things that can go for a spin as they may be interrelated. While doing all these iterations you also have to ensure production feasibility, part availability for future. This is one reason why standard parts are used, it eliminates all these activities (cutting onions) from the picture.

Spike
Spike, So all these were not required for European market or S.A market? Can you post the link to the excel sheet?
When a vehicle with new design in totality being manufactured, yes i agree all the above are more than cutting onions.
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Old 6th May 2010, 12:33   #1472
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Speaking of practical mechanics, not just in the case of jeeps, but in case of cars also after market tuners can better than performance of the stock car by a large margin.
So why does not the mfr give the same specs?
The reason is
1. MFR has to meet ARAI specifications, emission regulations, safety and other stuff like that
2. When you go to aftermarket mechanic, you can make the vehicle of your choice, MFR must cater to wider demand.
Lets say Thar has 2000 units/month market in India.
Out of this 2000, 10 buyers are like hard core offroaders, and 1990 buyers are generic lifestyle 4x4 buyers.
The MFR will try the balance out stuff.
If something on the vehicle pleases 1990 and displeases 10, mfr will not listen to the 10. Its logical. Expecting the mfr to make a vehicle to cater to just the niche audience, and waste millions of dollars in R&D and finally alienate the rest of the crowd is childish.
MFR will give you a base, their textbook engineers, as you call them will simply design a jack of all trades master of none.
If you want a niche use model, you have to go to an after market mechanic.
Speaking of the aftermarked "real mechanics" as they are called, I have one question, do the jeeps they build out of army disposal meet ARAI regulations.
Can they meet emission regulations.
Can they reliably do cross country 1000kms non stop run without over-heating or braking down.
Can they drive non stop for 100kms on a uphill high mountain pass.

the cross country and high mountain pass requirements are totally useless to offroaders for weekend off roading, but when a mfr builds a vehicle, they cannot say "do not go on 1000kms trip, because if you do that vehicle can over-heat. Or do not start climbing a 100kms uphill road in the himalayas because we will overheat due to rarified air.

Speaking of IFS, if the majority of buyers had a problem with that, MM would not use them, but if 1990 out of 2000 have no issues, then they will built that.

This is true for any mfr in the world.
99% of Tata Safari buyers buy the Safari 4x2. 1% go for 4x4. So should Tata mass produce 4x4 safaris? Well they would not. Thats why you need to wait a month for special order to come through.

For a Mfr, its not just the engineering. Engineering and technical requirements are just a small part. In the end, the product manager has to justify the product.
The sales team has to be convinced that they can sell this product.

there are economical and legal issues(patents, design copyrights, Royalties etc., involved).

An offroader can go ahead and put a high powered isuzu diesel in their gypsy, and it will perform better than the stock 80 bhp engine. but can maruti do that? No they cannot. They have to license the engine, pay the royalty, and this will happen if there is enough demand.

The Swift with the Fiat engine was a reality because there is a demand of 10,000 such vehicles very month(swift dzire combo). So paying royalty was justified.

Regarding getting it right in the first go, hindsight is free. Many companies spend billions to come out with a new product, only to find flaws which nobody saw. This is true even in chip design world.

Why do you think garage shops in UK can easily take a light chasis, and buy a Ford Modeo engine, and build your pocket supercar, while mfrs have to offer such stuff at much higher prices.

A garage shop has little R&D expense. The engine they buy has already been tested, and the frame like lotus elise is already tried and tested.

R&D is no joke. Ask toyota. Inspite of having building cars for decades, they got caught with their pants down with the acceleration debacle.
Real world works very differently.

In the end its a choice between a vehicle that excels in palar challenge, or a vehicle which is an absolute all rounder, and meets all ARAI and emission regulations, and safety regulations.

Till date, I am yet to see a single Jeep created by Mechanics which does all 4
1. Meets ARAI regulations
2. Meets Emission regulations
3. Meets safety regulations
4. Can go on cross country trips(1000s of kms).

The day a "Practical Mechanic" builds such a jeep, I will bow to thee, but today I stand on the side of MM.
I will never buy a Thar like vehicle. I will probably buy a 4x4 scorpio given a choice. But what they have done with Thar is remarkable.
They are actually bringing out a niche product in an auto market which swears by small size and fuel economy. Its a bold move, and I applaud MM for that.
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Old 6th May 2010, 12:35   #1473
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Star aqua, I hope you know there is difference in requirements between M,N,O,P categories. Export and Domestic both are from different categories, also you cannot carry forward EEC/ECE certificates directly, that is a different loop altogether.

Spike
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Old 6th May 2010, 12:58   #1474
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Quote:
Originally Posted by tsk1979 View Post
Speaking of practical mechanics, not just in the case of jeeps, but in case of cars also after market tuners can better than performance of the stock car by a large margin.
======================
They are actually bringing out a niche product in an auto market which swears by small size and fuel economy. Its a bold move, and I applaud MM for that.
Hi Tanveer,

I was talking about "Scientific Engineering".

Try and address the technical points I have raised.

Did you understand the question I raised about IFS?

I want a Scientific explanation for rack & pinion, Mitsubishi, Force, TATA, are using RCBT boxes with Drag Links.

Regards,

Arka

Last edited by Jaggu : 6th May 2010 at 19:05. Reason: Please avoid Quoting entire large posts for short replies. It affects readability. Thanks
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Old 6th May 2010, 13:15   #1475
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Originally Posted by ex670c View Post
Hi Tanveer,

I was talking about "Scientific Engineering".

Try and address the technical points I have raised.

Did you understand the question I raised about IFS?

I want a Scientific explanation for rack & pinion, Mitsubishi, Force, TATA, are using RCBT boxes with Drag Links.

Regards,

Arka
Well my point is that technical and scientific considerations are only part of the vehicle design equation.
As people in the industry will tell you, cost plays a major role. Most of the considerations are Regulation and Economics based. You first define those parameters, and then decide on the scientific part. There are OEM supplier issues also involved.
For example, if using a slightly inferior tech can save 5000rs/per vehicle, economics will always win.
The question which the marketing and product team will ask is that by compromising on a certain component, what is the impact on market share.
If the impact on market share is offset by cost saved, the cheaper component will find its way into the product.
Scientifically, it may be better to use the components you listed, but economically(which is a cascading effect) the other component is a better fit.
I am not tuned to the 4x4 world, but let me present you a real world case.

The Tata 1.4 liter DICOR engine which found its way in the Indigo can easily output 90bhp, and stay well within tolerance limits for the engine.
However, that would involve using a beefier gearbox for the indigo.
Then 2 options arise
1. Use a beefier gbox with 90bhp engine, and sell it for higher cost
2. Use same gearbox, detune engine to 70bhp and save lots of money with economies of scale.

The buyer can go to any aftermarket ECU piggyback chip maker, and get 90bhp from the engine. In 99% of the cases, in normal driving, it will not stress the gearbox. But for a mfr, even if in 1% of the cases it results in premature gbox failure, mfr is going to let the higher bhp option go.

So the questions you are asking make sense from a technical point of view, but calling engineers "Textbook" and other such stuff is totally uncalled for. Remember, they also have to satisfy the economic and legal considerations, as well as market perception.

IF giving wider more off road capable tires leads to 2kmpl drop at ARAI testing facility, mfr will give the wider tire option a skip. It may not harm the suspension in any way, but even a 2kmpl drop in FE will be enough for MFR to forgo the better component.
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Old 6th May 2010, 13:32   #1476
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First mod will be tyres. Lets just establish what's the maximum you can go without compromising the drivetrain components
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Old 6th May 2010, 13:35   #1477
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Economics

Quote:
Originally Posted by tsk1979 View Post
Well my point is that technical and scientific considerations are only part of the vehicle design equation.
As people in the industry will tell you, cost plays a major role. Most of the considerations are Regulation and Economics based. You first define those parameters, and then decide on the scientific part. There are OEM supplier issues also involved.
For example, if using a slightly inferior tech can save 5000rs/per vehicle, economics will always win.
The question which the marketing and product team will ask is that by compromising on a certain component, what is the impact on market share.
If the impact on market share is offset by cost saved, the cheaper component will find its way into the product.
Scientifically, it may be better to use the components you listed, but economically(which is a cascading effect) the other component is a better fit.
I am not tuned to the 4x4 world, but let me present you a real world case.

The Tata 1.4 liter DICOR engine which found its way in the Indigo can easily output 90bhp, and stay well within tolerance limits for the engine.
However, that would involve using a beefier gearbox for the indigo.
Then 2 options arise
1. Use a beefier gbox with 90bhp engine, and sell it for higher cost
2. Use same gearbox, detune engine to 70bhp and save lots of money with economies of scale.

The buyer can go to any aftermarket ECU piggyback chip maker, and get 90bhp from the engine. In 99% of the cases, in normal driving, it will not stress the gearbox. But for a mfr, even if in 1% of the cases it results in premature gbox failure, mfr is going to let the higher bhp option go.

So the questions you are asking make sense from a technical point of view, but calling engineers "Textbook" and other such stuff is totally uncalled for. Remember, they also have to satisfy the economic and legal considerations, as well as market perception.

IF giving wider more off road capable tires leads to 2kmpl drop at ARAI testing facility, mfr will give the wider tire option a skip. It may not harm the suspension in any way, but even a 2kmpl drop in FE will be enough for MFR to forgo the better component.
Hi Tanveer,

Please don't involve economics to justify poorly executed mechanical system/vehicles.

I have every right to call engineers what I want; with in good reason as I have stated in my previous post.

1) The Design Team members do not own any JEEP (M&M)

2) Rack & Pinion Steering for IFS

3) 1 piece SFRA with a MLD.

How can they justify they have real world experience with M&M vehicles?

At best they have a lot of data on various M&M vehicles, and they think that is what is needed to improve or modify or build a vehicle.

When they point out our mistakes, we openly admit to being non-engineers, and copying the best in their vehicles

When we point out their mistakes, the feel shy, don't have the guts to respond, or it becomes a case of economic consideration.

All the above examples I have given are from production M&M vehicles.

Since you are not tune with the 4x4 Circuit, where M&M JEEPs form 90% of the crowd/market, I think you should pass this one.

Regards,

Arka

Last edited by ex670c : 6th May 2010 at 13:37.
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Old 6th May 2010, 14:35   #1478
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Regarding IFS, well a modern vehicle will always go for IFS.
Reason is handling, high speed stability etc., Remember the vehicle is for general audience, not weekend OTR audience. On road behavior is just as important as off road behavior.

Regarding Rack and Pinion, well isn't it getting more popular nowadays. It gives more steering feel and feedback.
Not to mention that its much cheaper to build and maintain and is lighter too. Economics wins here, and since the RCBT does not offer much advantage for an all rounder Rack an Pinion is a way forward, esp since the weight saving can have lots of benefits.

Regarding SFRA, sure semi floating will give more stress, but for 99% of the users it will be well within tolerance limits. Again the argument of jack of all trades.
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Old 6th May 2010, 15:38   #1479
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Quote:
Originally Posted by ex670c View Post
I have every right to call engineers what I want; with in good reason as I have stated in my previous post.
I am a s/w engineer. If someone calls me a copy paster, I would find that very demeaning. Even if I use a lot of google to copy paste code snippets. The overall logic and architecture is mine.
So while in your reason it may be justified. For me it would be very insulting.

Quote:
1) The Design Team members do not own any JEEP (M&M)
Just curious, have you met the entire design team and verified this statement.


Quote:
At best they have a lot of data on various M&M vehicles, and they think that is what is needed to improve or modify or build a vehicle.

When they point out our mistakes, we openly admit to being non-engineers, and copying the best in their vehicles

When we point out their mistakes, the feel shy, don't have the guts to respond, or it becomes a case of economic consideration.
IN any large organization, there are very clear limits on what we can say and write about in a public forum.
Maybe you are mistaking protocol for shyness?

Last edited by bblost : 6th May 2010 at 15:43.
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Old 6th May 2010, 15:52   #1480
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We are getting close to 100 pages. WHERE IS THE THAR?
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Old 6th May 2010, 16:48   #1481
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Quote:
Originally Posted by ex670c View Post
I have every right to call engineers what I want; with in good reason as I have stated in my previous post.
1) The Design Team members do not own any JEEP (M&M)
Hi Arka,

As you have raised this question I can't resist from answering. This is no way means I doubt the credibility or integrity of anyone over here. Please do not bring your creativity/wild imaginations into picture. This is a straight forward simple question.

What do you think how many people (leave forum members for time being) who own a Jeep also understand a Jeep?

Spike

P.S. Again, no offence meant )
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Old 6th May 2010, 17:06   #1482
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Quote:
Originally Posted by tsk1979 View Post
Can they meet emission regulations.
Can they reliably do cross country 1000kms non stop run without over-heating or braking down.
Can they drive non stop for 100kms on a uphill high mountain pass.
...

In the end its a choice between a vehicle that excels in palar challenge, or a vehicle which is an absolute all rounder, and meets all ARAI and emission regulations, and safety regulations.
So are you suggesting that the THAR is not TPC capable?

Quote:
Originally Posted by tsk1979 View Post

I will never buy a Thar like vehicle. ...Its a bold move, and I applaud MM for that.
I agree with you that the THAR is a bold move - I do not know your personal preferences but old wine tastes better in new bottles?

Quote:
Originally Posted by tsk1979 View Post
The question which the marketing and product team will ask is that by compromising on a certain component, what is the impact on market share.
If the impact on market share is offset by cost saved, the cheaper component will find its way into the product.
Cost is not the case with ALL manufacturers SIR. SAFETY IS...

Quote:
Originally Posted by tsk1979 View Post
Regarding IFS, well a modern vehicle will always go for IFS.
Reason is handling, high speed stability etc., Remember the vehicle is for general audience, not weekend OTR audience. On road behavior is just as important as off road behavior.
Sir, there is something called Solid AXle COIL SPRING. The reason why IFS is not preferred in an OFfroad vehicle is because the wheel alignment gets disturbed very very easy especially in a vehicle the class of the THAR. This will lead to unwanted visits to the service centre / mechanic etc etc.

Quote:
Originally Posted by bblost View Post
I am a s/w engineer. If someone calls me a copy paster, I would find that very demeaning. Even if I use a lot of google to copy paste code snippets. The overall logic and architecture is mine.
...

IN any large organization, there are very clear limits on what we can say and write about in a public forum.
Maybe you are mistaking protocol for shyness?
If you are a s/w engineer, then why copy paste a code in the first place? If the architecture is yours then the code has to be yours unless you want to copy architecture too:

I agree with your second POV, but you also cannot assume that the forum will buy what you sell and when the forum wants clarification, please answer with specifics not generics!!!

Quote:
Originally Posted by Spitfire View Post
We are getting close to 100 pages. WHERE IS THE THAR?
The THAR is very much in M&M and if you are nice to M&M and travel to the next OTR near mumbai, you can see it in flesh performing the show

If you are wondering when is it going to come to the market and at what price, your guess is as good as mine
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Old 6th May 2010, 17:34   #1483
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Quote:
Originally Posted by headers View Post
If you are a s/w engineer, then why copy paste a code in the first place? If the architecture is yours then the code has to be yours unless you want to copy architecture too:
Sorry for going OT.
But you are definitely not a s/w developer right.

Mind you I mean s/w developer and not s/w programmer.

I work in one of the worlds largest s/w companies with a new and rapidly evolving tech-stack. There is simply no way I will keep track of the latest way to traverse to the n'th child in the n'table of a nested array. I simply google out the code to find the right API and do it.
Not only does that save me time, but with experience one can also find the more generic way of doing it.

More generic way because that simply means I have code that can be debugged. Now please don't tell me, code must not contain bugs. It will.

So I repeat, its one thing to copy paste code, Its a completely different thing to create and deploy applications.

Once again, Sorry for going OT.
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Old 6th May 2010, 17:49   #1484
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Dear all - I think I may want to add a few thoughts here. We have always maintained that we welcome and value differentiating opinions as only good can come out of it. I would take this opportunity to make it very clear that we mean no disrespect for anyone on his /her capability. There are many good things which can happen due to differing views expressed in this thread. I believe that "maramari" is a very healthy thing to happen as long as it remains within the realms of decency and regard for all. Personally I do not think anybody has transgressed this boundary and I do not think any TeamBHPian would ever do so.

That said, I actually owned a red CJ3404WD MH01P8300. I was its registered owner for exactly one year. I skimped and slogged and saved and bought it brand new for Rs.2,69,292.00. I had to perforce sell it as I needed money to buy a house (house appreciates / car depreciates). This was way back in 1995. However, without my name being in the RC book (which had M&M on it), I can hazard a guess of saying that I was the owner of following Mahindra vehicles by proxy.

MRS1581 - 1962 FC160P4WD prototype
MRX8592 - 1962 Jeep Station Wagon 2WD
MRG7962 - 1971 Jeep CJ3BLHD4WD
MMB8466 - 1975 Jeep CJ500D4WD
MMF4479 - 1978 Jeep CJ4A4WD
MMF4478 - 1978 Jeep CJ4A4WD fitted with prototype XDP4.90 engine, given to Himalayan Rally Association as official vehicle
MMG7627 - 1981 CJ5 Iran Jeep 4WDLHD fitted with F4134 engine
MXZ8702 - 1982 CJ5 Iran Jeep 4WDLHD fitted with Mitsubishi 4G54 engine & choice of KMT90 transmission with mechanically actuated clutch / Mitsubishi transmission fitted with hydraulic clutch
MMB7342 - 1975 first prototype Ambassador car fitted with XDP4.90 engine
MMH7432 - 1982 second prototype Ambassador car fitted with XDP4.90 engine mounted at 20 degrees inclination angle (one of the original design adaptations from Peugeot, with original dry type in to out air cleaner mounted on the tappet cover)
MWN1205 - FC360DP straight chassis prototype
MWN1207 - FC360 straight chassis prototype with Perkins P4 engine
MH01P2540 - 1994 CJ340DP4WD Invader prototype with doors which I used for numerous Great Escapes
MH01P1884 - 1994 first prototype MM540DP4WD fitted with BA10 transmission
MH01P1885 - 1994 first prototype MM540XD4WD fitted with BA10 transmission
MH01P7493 - 1994 Armada4WD used for Silk Route expedition
MH15K2580 - 1995 Armada4WD used for hands across the borders expedition
MH15AH2919 - 2000 my first CTC (cost to company) Armada2WD
MH15AH8544 - 2003 first prototype Scorpio REV1164WD petrol RHD
MH01MA3662 - 2003 first prototype Scorpio REV1164WD petrol LHD
MH15BN7657 - 2007 first prototype Scorpio MHawk VKX2WD
MH15BX3184 - 2007 my first CTC ScorpioLX2WD
Getting registered next week - 2010 my first CTC BoleroVLX2WD

Plus 20 Mahindra 2 wheelers having AP registration in 2005, as I was one of the team members who sparked the idea / initiated and progressed the M&M 2 wheeler project.

I better get back to work fast before you guys hammer me for filling 100 pages of this thread..

Best regards,

Behram Dhabhar
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Old 6th May 2010, 17:55   #1485
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Quote:
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So are you suggesting that the THAR is not TPC capable?
No I am suggesting that an old "practical mechanic jeep" may do better than Thar in TPC. However, as an all rounder. Cross country/Trail driving/Offroading Thar will whip it.

Quote:
I agree with you that the THAR is a bold move - I do not know your personal preferences but old wine tastes better in new bottles?
New engine with modern ergonomics, I would say new wine in old bottle(jeep like body). As for my personal preferences, I am more a off road trail driving guy, like himalayan trails, mild river beds, some sand. So SUV suits me more as places I go to have extreme temperatures.
Quote:
Cost is not the case with ALL manufacturers SIR. SAFETY IS...
Cost is a very important case with most Mfrs. Not just in automobile design. Unless its a supercar, MFR will do anything to keep costs in check. Even in a premium segment vehicle.

Quote:
Sir, there is something called Solid AXle COIL SPRING. The reason why IFS is not preferred in an OFfroad vehicle is because the wheel alignment gets disturbed very very easy especially in a vehicle the class of the THAR. This will lead to unwanted visits to the service centre / mechanic etc etc.
I think adequate testing would have been done for the same. In normal off road activities(read not extreme off roading), it will hold. Remember, Thar is not for extreme offroaders. Infact even in the west people who do extreme off roading modify their vehicle of choice extensively. For example, more closer home Khan_sultan has modified his gypsy. Stock gypsy is totally different.
Quote:
If you are a s/w engineer, then why copy paste a code in the first place? If the architecture is yours then the code has to be yours unless you want to copy architecture too:
If you were designing a new car, would you reinvent the wheel or simply take the wheel from the market? There are fixed mathematical algorithms which are fundamental. these are used in softwares across all companies. For example for binary search you would copy paste the algorithm which suits your design requirement, not rewrite it all time
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