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Old 18th February 2008, 02:46   #31
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Hi all!

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Originally Posted by Batla View Post
Forza Italia!

Congratulations Ignazio for this detailed, precise and accurate explanation. I got a similar one (not as good by the way) from a Mahindra Scorpio (Goa) salesperson regarding the LSD on their pick-up.

Batla (from France)
Thanks Mate! Where in France?

Quote:
Originally Posted by Steeroid View Post
Tell 'em Ignazio. You will be surprised that in the land of your Elefant, it isnt considered 'good enough' to go offroad.

But then again, if you really know us you wouldnt be surprised.
They will be shocked of what we let Safari and TL do!!! Next 8/9 March I'll go out with same friends from Tata club Italia... I'll post some pictures...

Quote:
Originally Posted by tsk1979 View Post
Wow! The second video is amazing. The safari had one wheel in air, and two stuck in muck.
But I guess the Tatateam videos show modded safaris? Or are they stock with additional underbody protection.
Generally they are stock, just higher tires and maybe some little turbo tuning to have some more hp, that is it...

Quote:
Originally Posted by adc View Post
Looks like the Eaton Elocker is the most suitable for highway purpose as well as for moderate offroad. It maintains an open differential [not default LSD] in highway runs and locks otherwise when needed by a simple switch operation.


Again a whole lot of thanks for your detailed replies to all the questions and observations. All these knowledge is more than enough for me now, will bother you up again if and ever I think about converting the 2wd Safari LX to a 2wd Safari LX LSD or Rear Locker!!!
Thanks, it has been a pleasure, more than happy!
If I will (as I hope) install the ECTED, I'll certainly post some pictures...

Ciao ciao for now!

Ignazio
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Old 27th February 2008, 12:11   #32
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Both of these situations were happening in the post I mentioned earlier


Situation 1>
Quote:
Originally Posted by adc View Post
I was assuming a situation [2wd rear wheel LSD] in slippery mud whereby only one wheel always gets the majority of traction due to slippage of the other tyre and thus the car spins around
The 2wd Patrol was fishtailing crazily, but this would need constant corrections from the steering to be able to move in intended direction. On a "open" differential though any loss of momentum would have stuck the car up. However the case was here the car had gotten itself in a situation represented below. It was mostly fishtailing and was always getting into this situation.

Situation 2>

Quote:
Originally Posted by adc View Post
or where two wheels loose traction due to a patch of very slippery mud and the LSD becomes useless. However in real life situation this is not so and one of both rear car tyres are having traction at any point in time or simultaneously, and then will be able to get out from the stuck situation.
Thats where you need to have the possibility of the front axle to bail you out. This isn't a very unreal scenario, as I mentioned was happening on a 2 inch thick mud track.

But the real fun here was to see the big 4x4 dump trucks.(they used to take a different route though)

Last edited by 1100D : 27th February 2008 at 12:16.
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Old 27th February 2008, 20:59   #33
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Hey guys got these details on one of the website while finding some details about it and hope it might solve your issue on knowing how it works and the website details are mentioned below where i was able to find out these details

Limited Slip Differential

Limited Slip Differentials (legal LSD)

Limited-Slip (or Traction Lok - the Ford name, or Posi-Traction, GM name) is a function of the differential allowing one wheel to spin only a percentage faster than the other. This has its advantages in allowing more traction, especially during hard cornering, because a normal or "open" diff will allow the inside wheel to lose traction and spin as fast as it wants, while the outer tire (with most of the traction anyway) just freewheels. This is generally opposite of what you want to have happen. A Posi unit will allow the inside wheel to spin only so much faster than the outside, at which time it transfers torque to the outer wheel, increasing power that's transmitted to the ground. This is achieved by several methods. The most common is with clutch packs in the differential that are set to a "breakaway" threshold. Another semi-common way is using viscosity (Viscous LSD's), which use a special differential fluid to control the amount of slip. A third method is a Torsen type, where there's a worm gear and pinion (the theory being the worm gear can rotate the pinion, but not vice versa). In effect, you can think of cars without Posi to be "one wheel drive" and cars with Posi to be two-wheel drive.
Picture a car rounding a corner; the inside and outside wheels have to carve differently sized circles. Because of this, they must travel at different speeds or independent of eachother. The non-drive wheels are no problem, but the drive wheels are connected to eachother via halfshafts, ring gear and driveshaft. This is where a normal OPEN differential comes into play. It allows the drive wheels to spin at different speeds when rounding a corner (the tires and drivetrain would bind and not corner as well without it). The problem with totally open differentials is that you cannot control how much and when they slip. Trying to accelerate on ice or gravel will usually result in only 1 tire spinning, producing plenty of smoke, but no go.

The limited slip differential does much the same job as the open, except (and nearly all OEM LSD's are like this...) there is a viscous fluid inside the differential that heats up and becomes VERY sticky/gooey when the two sides (either the two wheels or the two differentials - like on the Mitsubishi GTO and Eclipse AWD systems) spin at greatly different speeds (say, when one tire begins to spin wildly on ice or loose dirt...). The two sides are then locked together in order to prevent all the engine torque from going to the slipping wheel. It's basically a traction control device. High performance sports cars use them to put power down at a standing start and when powering out of corners. Trucks and minivans use it to keep the vehicle from spinning in adverse conditions (snow, ice, gravel, freak rain storms, etc.). Most AWD (as opposed to 4WD) systems emply some manner of viscous limited slip in order to transfer power to the other set of wheels when needed, but avoid it to avoid drivetrain wear and improve fuel economy. This is what Subaru means by "sending power from the wheels that slip to the wheels that grip...". Makes it sound like there's a big decision making process when you hit adverse
conditions, but not really.

Last edited by Rehaan : 28th February 2008 at 00:31. Reason: Formatting tags removed.
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Old 27th February 2008, 21:36   #34
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Maybe offtopic regarding 4X4 but pertaining to LSD.

I had the opportunity to drive a Honda Civic equipped with a Qaiffe LSD on ice/snow. I used to get to drive similar stock cars. There was a huge difference. The LSD equipped car used to pull from before the apex of a corner much cleaner than the stock ones (which needed constant throttle modulation as the inside wheels were happily spinning giving no power to the outside wheels and thus understeering like mad). I would admit there would be difference in tyres, but not that much.

Slippery conditions, LSD helps a lot whether RWD,FWD or 4WD.

Last edited by 1100D : 27th February 2008 at 21:38.
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Old 28th February 2008, 14:16   #35
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that was a question- so if i am going on ice / snow should i engage 4H or 4L? considering i would be driving on conditions are not ideal?
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Old 28th February 2008, 14:37   #36
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On snow/ice, unless you are descending a very steep hill and need engine brake, 4H is the best.
Ciao!
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Old 29th February 2008, 19:25   #37
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I dont think the tata even use Dana Spicer axles, and the axle housing on the Tata safari does not look like the Dana 44's at all. The HM RTV uses what looks more like a Dana 60, Dana70(and i seriously doubt if the dana 44's can even take the weight of the load,especially since its more or less over loaded most of the time). Even the new Mahindra loadkings have what look like a Dana 70(its bigger that the RTV's for sure,which i assume is a dana60). How do i know???? Well ,i have a Cummins 6Bt lying around with Bosch ve Injection pump in it. The ve has been tweeked by to take out 320Hp and 96.5kgm torque. Its shoehorned to a heavy duty 4speed(7.13 crawl ratio) from the Nissan Carrier 1-ton. Now i am looking for some heavy duty axles. The choices range from a shortened axle from the Tata 407 4x4,which eventually i will have to modify for disc braks at the front(it uses a wider lug ratio, so finding a disc set and wheel is going to be a problem), or any vehicle which uses Dana60-70 for the front end(coz the rear ones i found in the mahindra)......Whats it going into????? a 1962 Nissan Patrol aka the JONGA.....
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Old 29th February 2008, 23:07   #38
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@brutus: Belive me my friend, it is a D44 have a look to this thread....
http://www.team-bhp.com/forum/4x4-of...-vehicles.html
Lots of experience on this vehicle and 21 years of driving license....
Ciaocheers:
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Old 29th February 2008, 23:29   #39
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Correction ----Its a 44 in the Tata, and the TATA uses two types of axles, dont know about the lighter duty ,but the other one is surely something that looks like a Dana60-70....
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Old 1st March 2008, 00:18   #40
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this is off topic but , brutus ,where did you get 6BT engine from and how much did it cost? try getting your hands on an ZF transmissions....since you have an engine get a proper gear and diff, dude ...it'll be a beast........
Thats one heal off an engine...
I was looking out for one ? please let me know.
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Old 1st March 2008, 01:07   #41
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mis-spelled -not tata that uses 2 types of axles but that HM RTW. I have seen the Safari with a different axle too. The housing cover on it looked more like a chrysler 9 1/4" than anything esle. Wonder where all tat buys its axles from. The biggest heavy-duty axles they use are from eaton, then they use old mercedes type axles in the army trucks(only the rear ones-which have the diff lock) and silisbery's in the front. Then what the TATA407 4x4 uses is totally different from what i've ever seen.
The axles on the Nissan Patrol Jonga are way stronger than Dana44's, so i need something better.Presently am thinking of assembling an custom axle that uses the differential housing of the Patrol(i've got diff-locks made for it that am also sending to some nissan folks in oussie-land and the states), and shartened and resplined shafts from the Tata 407 truck with the brakes from the pajero.
I bought the cummins from Mayapuri,Delhi and it cost me Rs45,000. But you really dont want to use such a noisey motor.Its even noiser than the mercedes motor used in older Tata trucks(and now the same motor is available with a turbo, produces about the same power as the cummins, and costs the same)
The are three versions of the cummins 6bt 5.9l available here(although the Tata novus uses a cummins 8.3). The 1st version uses the Bosch A type inline injection pump.Makes anywhere between 125-155hp,and the more powerfull ones use an intercooler too(although i dont have any more space to fit the intercooler into,the jonga has two small windows on the grill. The lower one will be covered by the PTO winch,leaving anly the upper window,about 21x10inches wide, so it has only enough flow for a radiator ,not an intercooler)...

The second version uses the Bosch Ve type rotary injection pump. Makes 160-180 hp.both version use an intercooler.This motor is a bit tougher to locate that the A -types....
The last uses a Bosch P type injection pump, the most powerful,it produces 210-230Hp.Uses a massive intercooler and unlike the rest, uses a waste-gated turbo housing
I would stay away from the A-types, although the pump is very reliable and by far the most fuel-efficient of them all, it just does not produce the kind of power i want.
The P-types are the most powerful. They can been tweeked to produce 700hp and 140kgm of torque. Even the goverened rpm's can be tweeked from 2500rpm max to 4000rpm max. But it needs a lot of stuff from the states for the mods which will cost you more than the vehicle itself.
The ve's are the best. Only by turning a couple of screws and using the waste-gated turbo from the P-pump version can fetch you about 350hp.Even the rpms can be upped to 3200rpm by just changing the spring(also available locally) now that's cheap power.
I cannot go for tata gearboxes coz dont have that much wheelbase in the patrol(only 86.6"). even with the 4speed its going to be a very tight fit. Since it overly still ilight vehicle by any standards(even with all these things put together), i can probably make bo with the standerd axles, coz there is not enough weight on the axles to push them down for grip, so all the evtra torque would be uses in slipping the wheel and not stressing the axle. But i really dont want to take chances.....
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Old 1st March 2008, 01:20   #42
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Also the Most powerful light duty axles available here are the rear Full-floating units used in the Mahindra Bolero, or even the mahindra mini-buses. Looks like a Dana44 for sure, but let this be a warning to everyone. Almost all these axles were later upgraded from the original dana's with inhouse R&D. Even the full-floater available in the bolero is one of its kind. And maybe that goes for the Tata units too, who knows, so its better to find out what the slpine count and diameter is before you go looking for expensive upgrades like a dana44 diff-lock or something.....they use different parts here than whats atandard for dana44's around the world. How else do you think a dana44 rated at 1700 Gross weight worldwide does duty in a 3 ton payload mahindra minibus which weighs 4,500gross .....
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Old 1st March 2008, 12:54   #43
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So you have an engine with Two valves not the 3 valve head?
Also, try getting your hands on the diff from an Eicher I think that should work with your setup, also the gear box should be able to handle the power.or tey getting these from the AMW guys, they import all the stuff from germany and other places ,they use cumnis as there engine supplier and ZF for tranny, I have no idea about the diffs thought, but will try to find out.
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Old 1st March 2008, 16:21   #44
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Both the Cummins and the Zf are made here under licence.tata has been using them for ages,AMW has just entered the show. Tata actually uses a variety of axles, heavy duty axles i know about but they are just too massive for my application. I need info only for the lighter duty axles used on the Tata407 and Tata709. The eicher and swaraj unit are basically copies of Toyota heavy duty units, and anyways they have for too a low ratio for my purpose.
And The cummins did not have a 3vavle/head version. The first-second generations were all 2valves/head and had the ve and the P pumps. The 3 generation was the 4valves/head, dut it has a electronic pump(which is something that does not go well with our truckers here). So we just have the 12 valves units here ,not the 24 valves. There have been instances where the p-pump has been fitted into the the 24valves head in search for more power, but that too is quite a modification....
My motor is a VE unit, 12vales, intake modified to run without I/C, Waste-gated 12cm2 turbo from the p-pump version, soon to follow up on exhaust headers, a boost elbow,custom fuel pin, 3200rpm spring, some gauges, and all the tweaks to get it near 300hp(would get 350-400 with a I/C, but dont have the space). If it all follows up well, then its time to get a P-pump cummins for my 4x4 Bolero.
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Old 1st March 2008, 19:31   #45
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Sorry for the typo, I was asking about 4 valve head... just queries can we get the 24 valve head engine in India?
You are trying to fit this unit in the Bolero
Hey u should start a new thread on the mods your doing with pics, real interesting stuff your doing. I had tried my hands at diesel mod on my Jeep. will like to see how your mods are.
I have experience with both Tata and Eicher trucks, and I find that eicher components are more reliable [hence stronger ]than those of tatas, so I suggested you look into these.
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