Team-BHP - M&M Launches the new improved Scorpio

Quote:

Originally Posted by ram

A good suspension setup should ensure good ride quality without affecting handling and safety.

That being said, the objective of any multi-link suspension is to provide two conflicting characteristics, simultaneously:
1. High lateral stiffness (resistance to deflection due to side forces) for excellent handling
2. Reasonable longitudinal compliance, for improved ride quality with less NVH.

The information you have gathered refers to an IRS.
The term 'Multilink' commonly refers to an independent rear setup which the Scorpio is not. Its still very much a live axle. High lateral stiffness can also be obtained in a hotchkiss
by adding a 'panhard rod'. Hotchkiss can also have longitudinal compliance because of the shackle assembly which causes the axle to move rearward as it travels up. To add to that, you can also have rubber bushing based compliance.

Quote:

Originally Posted by ram

The elastokinematic characteristics are usually tuned up to minimise camber and track changes and correctly tune toe variations.

What toe variations?
The term SUV shouldn't be misused for anything without 4-wheel-drive.
That said, the Scorpio being a rear-drive station wagon, the central axis of elasticity at its rear axle should be positioned properly to toe-out under harsh acceleration and toe-in to improve stability when you let go the accelerator pedal.

Its a solid axle, so you're gonna have zero camber change and zero track change. As far as toe change, you get it only in roll depending on the kinematics of the 2 lateral rods and you want 'Toe-in' in the outer wheel to promote understeer. There is no toe change during braking or accleration.

Tata has this setup on their Sierra more than a decade and a half ago. As far as 4x4, there should be no reason not to offer it because the front suspension has not changed.

As far as ABS, there is no question that every vehicle needs it. But Mahindra's decision is probably driven by market research which showed that a large percentage of their buyer demographic is not aware of it and hence will not take the option. More over, in India safety is associated with the size and bulk of the machine which the Scorpio has plenty of.

Quote:

Originally Posted by suman

Quote:

Originally Posted by xentric

When I logon to the website the flash intro plays and then just stops! Anyone facing the same problem?

The site is AWFULLY slow to navigate, maybe a lot of people logged in today....I had a hell of a time trying to download their brochure, would you believe its a 45 MB file that will just JAM your printer (and network if you are on one) if you try printing it.

Dunno if it will work but try hitting the button "Skip intro" so you go on to the main page, you will not be missing anything significant

Dear friends:

I solved my issues with the Mahindra Scorpio website and its oddball "rar-compressed pdf". Here is my preliminary understanding.

Mahindra is fielding three models:
1) Scorpio STD
2) Scorpio DX
3) Scorpio SLX

The base STD model has no plastic cladding on the body sides. Also it has no voice-assist system nor remote locking, no air dams, no mud flaps, no rooftop ski rack, no power windows. It’s available with a fixed middle rear seat and optional sideways benches.

The DX has black unpainted plastic cladding, airdams, mudflaps, power windows, rear-window wiper, and legroom adjustable middle row seat.

And the SLX is Mahindra’s fully-loaded model with body-color painted plastic cladding, airdams, mudflaps, power windows, rear-window wiper, and legroom adjustable middle row seat. It also has the exclusive voice-assist system, remote locking, intelligent rain-sensing wipers, illumination delay (Mahindra calls it "Follow-me-home")

All three models are available in black color. Mahindra calls it "Noble Black". And the metallic "Engine Silver" color. The DX is available in "Apple Red" color. The top-end SLX model is available in the hot "Passion Red" and metallic "Amber Red".

The two-wheel-drive model has coil springs at all four wheels and an anti-roll bar. The rear has the Lotus-designed multi-link coil-spring suspension.

The four-wheel-drive model has torsion bar front (like the old Ambasador) and coil springs and Lotus-designed multi-link coil-spring suspension at the rear.

Quote:

Originally Posted by triggercool

Does anyone have pic of new scorpio.......pls

For your viewing pleasure here are a few pictures of the new coil-sprung Scorpio.

Cheers…
Ram

Quote:

Originally Posted by Mpower

The information you have gathered refers to an IRS.
The term 'Multilink' commonly refers to an independent rear setup which the Scorpio is not. Its still very much a live axle.

Mpower, you're absolutely right on that! You would have noticed that the picture in my post...

...clearly shows that the Scorpio has a live axle rear-end.

Quote:

Originally Posted by Mpower

High lateral stiffness can also be obtained in a hotchkiss by adding a 'panhard rod'. Hotchkiss can also have longitudinal compliance because of the shackle assembly which causes the axle to move rearward as it travels up. To add to that, you can also have rubber bushing based compliance.

You're not wrong on that either! I do have my drawings of Panhard rods and Watts linkages locating live axles from pre-Internet decades now. I know that Hotchkiss have longitudinal "parallelogram" compliance via the shackle-hangers on which the leaf-spring assemblies are hung à-la-Mahindra MM540.

Quote:

Originally Posted by Mpower

As far as ABS, there is no question that every vehicle needs it.

Mpower, I would like to humbly submit that I have been driving cars for over 30 years and hold driving licenses in the US, the Netherlands, Australia and Singapore in addition to India. The only serious collision in over 3 decades I've had happened in Sunnyvale, CA because of ABS.
With over a million miles of off-road, freeway, desert and ice-driving experience on me, I posit that ABS is unnecessary in every vehicle. My uncle who holds worldwide patents in electronic traction control at the erstwhile Delphi automotive also agrees with me.

Quote:

Originally Posted by Mpower

But Mahindra's decision is probably driven by market research which showed that a large percentage of their buyer demographic is not aware of it and hence will not take the option. More over, in India safety is associated with the size and bulk of the machine which the Scorpio has plenty of.

Our opinions on Mahindra's decision or lack of it, based on buyer ignorance and misperceptions of threat to life and limb is pure conjecture, not to mention consumer-hostile -- What they don't understand won't harm'em -- thinking!:)
Would Ralph Nader approve?

Quote:

Originally Posted by veyron1

don't think that design is flawed in the primary; the qualis had almost the same design (i think), and it's handling was okay; mahindra just skewed the dynamics from the design stage itself, i guess......

You are bang on Veyron. Suspension design is sort of like cooking up a gourmet dish. People think that by adding the same ingredients as the master-chef they can match the taste. But sadly its not
true...need to know how to put if together and tune it. People have been trying to copy BMWs dynamics for years but still nobody has come close. Heck the Ambassador has Hotchkiss and people even today swear by the ride quality.

Quote:

Originally Posted by veyron1

@Mpower; isn't that a panhard rod in the rear suspension pic of the scorpio? (rod connecting link from top right axle tube towards left chassis long member, parallel to chassis cross member/tube).

p.s- do you think that the parallel mounting for the rear damper might prove stressful in the long run due to it's rigidity (check out the chassis mounts)?

It does look like a panhard rod although I am not able to see it completely. (looks like a CAD model) In any case it has to have either that or a watts linkage to locate the axle laterally.

I'm not sure I understood your 2nd question ?? You mean parallel to the spring.

Quote:

Originally Posted by ram

Mpower, I would like to humbly submit that I have been driving cars for over 30 years and hold driving licenses in the US, the Netherlands, Australia and Singapore in addition to India.
With over a million miles of off-road, freeway, desert and ice-driving experience on me, I posit that ABS is unnecessary in every vehicle. My uncle who holds worldwide patents in electronic traction control at the erstwhile Delphi automotive also agrees with me.

RAM, I guess I should have worded my sentence differently. I meant to say every vehicle out there could benefit from ABS.
Keep in mind, the average driver is not as skilled as you when it comes to modulating brakes to prevent lockup.

I myself have been living in the American midwest with its snowy winters for many years now. Not sure about Holland, but we sure get more snow than
Singapore, Australia and California combined. I feel my ABS coming on at least 10 times a year. ABS is like having insurance policy, just because you never used
it in 10 years dosen't mean that you could have gotten away without it.............. because you never know when you are going to need it.

Reasons why ABS is needed in India (even though we dont have snow)

Chaotic and unruly traffic means more 'sudden brake' situations
Dogs, cattle and crazy homo-sapiens running across the street.
Presence of dust/mud and fine gravel on roads = low mu = which advances the lockup threshold.
Poor road design causing rain water not to drain properly = puddles = low mu = which advances the lockup threshold.
FE obsession which leads to 'undertyred' cars = which advances the lockup threshold.
Soft suspensions means more brake dive = more load transfer to front = which advances the lockup threshold.

As far as the Scorpio's buyer demographic goes, that's purely my opinion based on what I observed in Bangalore and Chennai. The urban sophisticate types
who drive Honda Citys and have travelled abroad and used the latest cars, know about things like ABS and demand it and dont mind paying 30K extra for it.
Mahindra owners tend to be the more dhoti clad rustic types. (hope I am not stirring up something here!) and care more about 7 seater capability and diesel economy.

If you look at the evolution of the automobile or any other product, things have been constantly getting better. There are many features today that
we take for granted like servo disc brakes, power steering, 5 speed, crash tested bodies, EFI, etc etc. None of these were around on cars 20 years ago but still life went on. Some cars had it but they were considered premium and luxury just like ABS today. As we go into the future Airbags and ABS etc will become standard features on most cars and our kids will take them for granted. Its all about making progress in our standard of living.

Quote:

Originally Posted by Mpower

Chaotic and unruly traffic means more 'sudden brake' situations
Dogs, cattle and crazy homo-sapiens running across the street.
Presence of dust/mud and fine gravel on roads = low mu = which advances the lockup threshold.
Poor road design causing rain water not to drain properly = puddles = low mu = which advances the lockup threshold.
FE obsession which leads to 'undertyred' cars = which advances the lockup threshold.
Soft suspensions means more brake dive = more load transfer to front = which advances the lockup threshold.

Mpower,

Very well articulated thoughts. Thank you.

You're absolutely right that servo disc brakes, power steering, 5-speed, crash tested bodies, EFI, etc have improved the car experience in India.

And you're absolutely spot-on about more 'sudden brake' situations.

I don't have any problem with ABS and airbags per se. They're well-designed, continuously improved and actually work in
exactingly stringent designs like e.g. an E-class Mercedes-Benz.

How easy to goof?
But 5-speed gearboxes are simpler contraptions, inherently amenable to experimenting with idler and driven gear ratios.
And EFI can actually be independently developed overseas and incorporated into an engine by an Indian manufacturer.

However, both ABS and airbags are not "import and bolt-on" commodities.
Both ABS and airbags need to be customized for the specific cartype they're used in.
Isn't that situation, completely beyond our manufacturers commercial mindsets?

Early airbags were proved to be of questionable value. In some situations they actually caused harm.

Unlike in a developed country, most Indian road surfaces (or lack thereof) exhibit excessively wide diversity in quality.
ABS functions best on homogeneous surface -- Smooth concrete without holes or large cracks or dense, smooth smooth finish asphalt, especially sealed with "Jennite". An old asphalt surface with an open, porous, broken surface covered with loose gravel can confuse the ABS.

Wet mud, spread out loose sandy patches, mixes of broken asphalt, bullock-cart-tracks and loose gravel on third-world roads can actually defeat the value of ABS, result in longer braking distances and crashes.

ABS is by no means perfect. And low budget-cars are likely to have the world's simplest ABS systems.

Re-education
ABS requires the driver to re-learn his feel for the car.
Otherwise he can expose himself and his passengers to potential disaster.
Proper usage of ABS brakes in a critical stop situation requires the driver to press the pedal hard and hold it down continuously despite unusual sounds and vibrating pedal, allowing the system to rapidly and automatically pump the brakes, until the vehicle stops.

How alien is that to us?

An “ABS event” will startle the typical Indian driver with its unusual sounds and feel. The driver typically reacts by easing off the brake pedal or, worse yet, pumping it.
Both of these reactions will lead to longer stopping distances and a potential crash!

In cars with conventional brakes, drivers typically pump the brakes.
Who is going to teach every Indian driver the correct, “Stab, Stay and Steer”, ABS technique?

The wedge of sand and loose gravel built up by the locked wheel reduces stopping distance. You lose that advantage with ABS and see increased stopping distances.