Team-BHP > 4x4 & Off-Roading > 4x4 Technical
Register New Topics New Posts Top Thanked Team-BHP FAQ


Reply
  Search this Thread
4,810 views
Old 23rd December 2007, 11:58   #1
BHPian
 
Alfa_Kilo's Avatar
 
Join Date: Apr 2007
Location: Jaipur
Posts: 328
Thanked: 13 Times

Quote:
Originally Posted by nitrous View Post
The GV has differential locks and 4L.
And with its ECU et all, it might understand what the driver is trying to do.
In porsche 4x4s, there's something called descent control which helps in maintaining a low speed.
The hill descent system, also found in LRs works by using the ABS to brake the wheels and prevent the vehicle fron exceeding a certain speed limit. Electronic systems cannot make any significant changes to engine braking. Exhaust brakes (or exhaust retarders) do make quite a lot of difference though, and are found on most heavy vehicles.
Alfa_Kilo is offline  
Old 23rd December 2007, 19:55   #2
Senior - BHPian
 
headers's Avatar
 
Join Date: May 2006
Location: Greater Chennai
Posts: 4,667
Thanked: 559 Times

Quote:
Originally Posted by Alfa_Kilo View Post
The hill descent system, also found in LRs works by using the ABS to brake the wheels and prevent the vehicle fron exceeding a certain speed limit. Electronic systems cannot make any significant changes to engine braking. Exhaust brakes (or exhaust retarders) do make quite a lot of difference though, and are found on most heavy vehicles.
Quote:
Originally Posted by nitrous View Post
The GV has differential locks and 4L.
And with its ECU et all, it might understand what the driver is trying to do.
In porsche 4x4s, there's something called descent control which helps in maintaining a low speed.

Still..whatever electronics we use..one cant change the engine characteristics.. Whether it has Diff locks or not does not matter here.. Pls note that Diff locks are used only when one needs it..in an odd situation where one wheel is in air or will go in air thereby the other wheel loses traction and power.. And Nitrous, we are not talking Porsche here but basic off roading stuff.. A porsche owner especially in India, will never want to take his vehicle to such terrains..!!

For all one cares, descent control may be limiting the engine speed to say 1500 RPM or so electronically.. still what matters is that we do 2 kmph and not 20 kmph at that speed!
headers is offline  
Old 23rd December 2007, 21:50   #3
BHPian
 
susan3004's Avatar
 
Join Date: Oct 2007
Location: Kapurthala
Posts: 384
Thanked: 263 Times

Quote:
Originally Posted by Alfa_Kilo View Post
The hill descent system, also found in LRs works by using the ABS to brake the wheels and prevent the vehicle fron exceeding a certain speed limit. Electronic systems cannot make any significant changes to engine braking. Exhaust brakes (or exhaust retarders) do make quite a lot of difference though, and are found on most heavy vehicles.
Exhaust brakes are very effective while decending downhill with loads full at the back, or when negotiating sleet or snow. Ashok Leyland Stallion 4x4 has this system and it gives a lot of confidence driving such a vehicle over others.
susan3004 is offline  
Old 26th December 2007, 09:11   #4
BHPian
 
Alfa_Kilo's Avatar
 
Join Date: Apr 2007
Location: Jaipur
Posts: 328
Thanked: 13 Times

Quote:
Originally Posted by susan3004 View Post
Exhaust brakes are very effective while decending downhill with loads full at the back, or when negotiating sleet or snow. Ashok Leyland Stallion 4x4 has this system and it gives a lot of confidence driving such a vehicle over others.
I wish manufacturers would provide e-brakes on lighter vehicles too, especially 4x4s.

OT: How capable are Stallions and 713s off road compared to MM550s and Gypsies? Does the Stallion have diff locks?
Alfa_Kilo is offline  
Old 5th January 2008, 20:49   #5
BHPian
 
susan3004's Avatar
 
Join Date: Oct 2007
Location: Kapurthala
Posts: 384
Thanked: 263 Times

Quote:
Originally Posted by Alfa_Kilo View Post
I wish manufacturers would provide e-brakes on lighter vehicles too, especially 4x4s.

OT: How capable are Stallions and 713s off road compared to MM550s and Gypsies? Does the Stallion have diff locks?
Oh! Light vehicles don't actually require exaust brakes; they hardly take any load!

Both Stallion and 713 are good off roaders. These have been going to places where MM and MG have been going.

But yes, every vehicle has its limitations....713 is easy to manage than a Stallion. The later looses direction more often than others. It is a shade better when in 7.5 ton mode. There are places where MM is better than MG and vice verca.

713 has got one lever to shift into 4L mode. It does not have a 4H. So to take out the work of 4H, we drive it in the 3rd/4th.

Both Stallion and 713 have diff locks.
susan3004 is offline  
Old 9th January 2008, 16:03   #6
Senior - BHPian
 
vinod_nookala's Avatar
 
Join Date: Aug 2007
Location: Mumbai
Posts: 1,737
Thanked: 430 Times
stallion & 713

Quote:
Originally Posted by susan3004 View Post
Oh! Light vehicles don't actually require exaust brakes; they hardly take any load!

Both Stallion and 713 are good off roaders. These have been going to places where MM and MG have been going.

But yes, every vehicle has its limitations....713 is easy to manage than a Stallion. The later looses direction more often than others. It is a shade better when in 7.5 ton mode. There are places where MM is better than MG and vice verca.

713 has got one lever to shift into 4L mode. It does not have a 4H. So to take out the work of 4H, we drive it in the 3rd/4th.

Both Stallion and 713 have diff locks.

Hey,
I have closely observed both the vehicles, i like TATA 713 both in terms of styling and refinement. Looks handsome beast and on high speeds it is silent than a stallion. Stallion has a typical 4wd tranfer case whine...not to my taste.

As far as off road ability is concerned both vehicles are fairly good, though i feel stallion needs more power especially for sand applications. Mere 160 horses not sufficient especially when u have to do speeds with load in 4wd high.May be AL YAK has got better power to weight ratios.

Also surprising that TATA 713 does not come with 4wd high. How is that one maintains momentum in sand or how does one manage in slippery conditions in snow in north india? May be one manages with 4wd low in 5th gear for speeds may be....
vinod_nookala is offline  
Old 11th January 2008, 23:34   #7
BHPian
 
Join Date: Mar 2007
Location: KOCHI
Posts: 368
Thanked: 96 Times

Quote:
Originally Posted by vinod_nookala View Post
Hey,
I have closely observed both the vehicles, i like TATA 713 both in terms of styling and refinement. Looks handsome beast and on high speeds it is silent than a stallion. Stallion has a typical 4wd tranfer case whine...not to my taste.

As far as off road ability is concerned both vehicles are fairly good, though i feel stallion needs more power especially for sand applications. Mere 160 horses not sufficient especially when u have to do speeds with load in 4wd high.May be AL YAK has got better power to weight ratios.

Also surprising that TATA 713 does not come with 4wd high. How is that one maintains momentum in sand or how does one manage in slippery conditions in snow in north india? May be one manages with 4wd low in 5th gear for speeds may be....

Hey,
Its not only the engine power that decides the performance of the stallion, but its whole driveline. remember its the only vehicle used by the Indian army with 7.5ton GVW at the himalayan heights. LPTA 713 is a smaller one with 2.5Ton GVW.
Transsenger is offline  
Old 15th January 2008, 23:18   #8
BHPian
 
Join Date: Feb 2006
Location: Chennai
Posts: 397
Thanked: 346 Times

The best descent control is provided by J-brakes or Jake brake. That is the right kind of engine braking for heavy duty. It employs a set of hydraulic lifters that act on the exhaust valve during the compression stroke.

There can also be retarders employed on the propeller shafts. The most effective being electrical retarders that produce eddy currents and slows the prop shaft down.

In any normal 4wd jeep , I have never come across a situation where 1st gear in 4 Low cannot handle
rrnsss is offline  
Reply

Most Viewed


Copyright ©2000 - 2024, Team-BHP.com
Proudly powered by E2E Networks