Go Back   Team-BHP > Buckle Up > 4x4 & Off-Roading > 4x4 Vehicles


Reply
 
Thread Tools Search this Thread
Old 4th August 2010, 23:30   #316
Distinguished - BHPian
 
Tejas@perioimpl's Avatar
 
Join Date: Sep 2008
Location: Bombay
Posts: 3,947
Thanked: 4,765 Times
Default

Quote:
Originally Posted by Samurai View Post
You were trying to get 10.5J rim for a 31x10.5 tyre? The ideal rim width for 10.5 tyre would be 7.5 to 9 inches. So your current rims are perfect.
Couldn't get 10.5j rims so bought these tyres else I would have bought the 11.5 ones.

Last edited by Tejas@perioimpl : 4th August 2010 at 23:39.
Tejas@perioimpl is offline   Reply With Quote
Old 4th August 2010, 23:38   #317
Team-BHP Support
 
Samurai's Avatar
 
Join Date: Jan 2005
Location: B'lore-Manipal
Posts: 22,042
Thanked: 13,488 Times
Default

The ideal rim width for 11.5 inch tyre would be 8 - 9.5 inches. Good thing you didn't get the 10.5J rims. BTW, 11.5 inch wide tyres on a Classic is extreme, too much rolling resistance and unsprung weight for the XDP engine.
Samurai is offline   Reply With Quote
Old 4th August 2010, 23:41   #318
Distinguished - BHPian
 
Tejas@perioimpl's Avatar
 
Join Date: Sep 2008
Location: Bombay
Posts: 3,947
Thanked: 4,765 Times
Default

Quote:
Originally Posted by Samurai View Post
The ideal rim width for 11.5 inch tyre would be 8 - 9.5 inches. Good thing you didn't get the 10.5J rims. BTW, 11.5 inch wide tyres on a Classic is extreme, too much rolling resistance and unsprung weight for the XDP engine.
True. That does make sense. Worked out good for me!

But, I'm seriously considering change of axles.
Tejas@perioimpl is offline   Reply With Quote
Old 6th August 2010, 11:40   #319
AVR
BHPian
 
AVR's Avatar
 
Join Date: Apr 2008
Location: Ahmedabad
Posts: 929
Thanked: 511 Times
Default

Quote:
Originally Posted by Tejas@perioimpl View Post
@4x4addict
AVR, what's the offset of the rims?
Don't know actually. More like an ArKane question to me.
Though I know that the 235s are just about as much as what the rims can handle because I see very minimal spacing on the inside and the tyres rub on the inside on full-turns.

Would spacers work or do I really need to change to alloys?

Adi
AVR is offline   Reply With Quote
Old 6th August 2010, 14:24   #320
Senior - BHPian
 
harjeev's Avatar
 
Join Date: May 2006
Location: New Delhi
Posts: 1,896
Thanked: 256 Times
Default

Quote:
Originally Posted by Tejas@perioimpl View Post
My bighorns are 31" x 10.5 x 15
Thanks for the update. I too am thinking of 31 x 10.5 15's but am leaning on MAXXIS Trepedors. (dont have the budget for the Bighorns) But still lets see.

Quote:
My original alloys were 6.5J with positive offset. I had to change them. I could not find a 10.5J rim so settled for 8.5J negative offset rally rims.
I'll go for something similar.

Quote:
I'm running the stock 4.88 dif. I have not noticed any significant difference / reduction in performance as of now. However, i have done a lot of slush runs and not major climbs, etc to feel the need to change to 5.38. Maybe after monsoons when i shift to dif terrain requiring more torque i may feel a difference.
Any idea if I can change the MM550 diff ratios to 5.38. I think that the standard in the army is 4.88 and the one on my 3B is 5.38. Also would it be a simple conversion or is complicated??
Quote:
The lift is scary no doubt and you are always scared of tipping over (although the jeep is stable, it's a mental block). I don't corner at fast speeds at all. I'm seriously considering shifting to mm550 axles which are 3" wider than the classic ones. It's help a bit with the stability.
Exactly my thoughts. As I would be lifting the vehicle by 3" (tyres) & 4" shackles I would have to compensate it with wider axles and wider tyres. So i'll get approx 4.5" from wider tyres and another 3" from the MM550 axles. Even when I put -ve offset alloys that would also increase the track width to some extent. Shouldn't it???

Also shouldn't the shocks also be replaced. Cauz after all this is done, the ride height would have increased by 7". This will drastically reduce the travel of the OEM shocks! I am no expert so am I making sense or have succeeded in making a fool of myself
Quote:
The lift and bigger tyres are a boon 100%. The ramp over angle has drastically improved!
So thats your stamp of approval. Thanks.
I am currently gathering info and would most likely start the modifications once I have my LHD 3B back from the workshop which should be later this year. Will have to wait till then


Quote:
Originally Posted by 4x4addict View Post
@harjeev: Shackle lift will only increase your body height but the lowest point in your diff and GC will not change. Only larger tires will increase your GC and improve your overhangs/rampover angles. When you put larger tires a shackle lift helps prevent the larger tires fowling with the body. A shackle lift alone is not very useful in my opinion.
Thanks Tini. I would go for shackle lift only when I change the tyres

Quote:
Originally Posted by genesis View Post
@Harjeev: Dont forget to budget for the power steering that you will have to put in to steer the bighorns!
Will definitely do that too? I am either thinking a PS or the normal steering box of a Bolero. I've heard that they work really well too. But drove a PS fitted MM550 the other day and it definitely is a boon!!! Who knows ;-)



@Tejas:
Buddy I read that you also changed the mounting and/or position of the shock absorbers. Any specific reason for that?
harjeev is online now   Reply With Quote
Old 6th August 2010, 20:20   #321
Distinguished - BHPian
 
Tejas@perioimpl's Avatar
 
Join Date: Sep 2008
Location: Bombay
Posts: 3,947
Thanked: 4,765 Times
Default

Quote:
Originally Posted by harjeev View Post

Any idea if I can change the MM550 diff ratios to 5.38. I think that the standard in the army is 4.88 and the one on my 3B is 5.38. Also would it be a simple conversion or is complicated??
Nope. It's not complicated. You can get the LSD version.

Quote:
Even when I put -ve offset alloys that would also increase the track width to some extent. Shouldn't it???
Hardly makes a difference

Quote:
Also shouldn't the shocks also be replaced. Cauz after all this is done, the ride height would have increased by 7". This will drastically reduce the travel of the OEM shocks!
I'm not facing any issues.

Quote:
I am either thinking a PS or the normal steering box of a Bolero. I've heard that they work really well too. But drove a PS fitted MM550 the other day and it definitely is a boon!!!
If you fit the bolero box, make sure the pulley used is of a larger diameter. Otherwise the steering becomes too sensitive and is scary at highway speeds.

Quote:
@Tejas:
Buddy I read that you also changed the mounting and/or position of the shock absorbers. Any specific reason for that?
Did not change it. I was thinking of changing it if travel was an issue. Since it isn't, no point in messing about.

@Adi: Spacers not recommended for offroading.

Last edited by Tejas@perioimpl : 6th August 2010 at 20:23. Reason: answered AVR (adi)
Tejas@perioimpl is offline   Reply With Quote
Old 23rd August 2010, 19:56   #322
Distinguished - BHPian
 
Tejas@perioimpl's Avatar
 
Join Date: Sep 2008
Location: Bombay
Posts: 3,947
Thanked: 4,765 Times
Default

Few issues:

Overheating still happens when driven fast (~90kmph) or at 60kmph with 4 passengers or on ghat sections. The radiator is new, coolant level doesn't change and the radiator cap is as per specifications. The electric fan manages to control the temp from approx 95 to 85-90 but is not enough.

A lasts few OTRs made me realize the disadvantage of the 31" with my XDP engine and 4.88 difs. The engine just can't take it! I need to get a better engine or change to 5.38.
Tejas@perioimpl is offline   Reply With Quote
Old 23rd August 2010, 20:13   #323
BHPian
 
Join Date: Dec 2009
Location: mumbai
Posts: 193
Thanked: 97 Times
Default

DCM is the way to go buddy !
garrett_t16 is offline   Reply With Quote
Old 23rd August 2010, 20:14   #324
Team-BHP Support
 
Samurai's Avatar
 
Join Date: Jan 2005
Location: B'lore-Manipal
Posts: 22,042
Thanked: 13,488 Times
Default

Do you have the thermostat? My thermostat was recently removed and it never crosses 60, in fact it remains firmly at 40-45 while driving in rains. I don't have electric fan either.

How's your water pump?

My Jeep heating problem became so severe at one time, I had to move all the heating related posts to a separate thread, which itself turned out to be 11 pages long. It even gave birth to two more cooling test run threads.

https://www.team-bhp.com/forum/techn...blem-jeep.html
Samurai is offline   Reply With Quote
Old 23rd August 2010, 20:58   #325
BHPian
 
gsferrari's Avatar
 
Join Date: May 2009
Location: Mumbai
Posts: 842
Thanked: 131 Times
Default

Quote:
Originally Posted by Tejas@perioimpl View Post
A lasts few OTRs made me realize the disadvantage of the 31" with my XDP engine and 4.88 difs. The engine just can't take it! I need to get a better engine or change to 5.38.
Just to understand this better what you are saying is that your wheel makes 1 full rotation for every 4.88 rotations of the transmission output. As the wheel diameter increases this means you cover more distance with every rotation. Therefore 4.88 rotations is now doing more work than with smaller wheels and therefore the engine is struggling.

So if you increase wheel diameter then it is better to increase the diff-ratio to 5.38 so that instead of 4.88, 5.38 rotations are needed for the same distance which makes it easier on the engine (less torque required and therefore more in store for tackling obstacles).

Do I have this concept sorted out here?
gsferrari is offline   Reply With Quote
Old 24th August 2010, 11:23   #326
Distinguished - BHPian
 
Tejas@perioimpl's Avatar
 
Join Date: Sep 2008
Location: Bombay
Posts: 3,947
Thanked: 4,765 Times
Default

Quote:
Originally Posted by Samurai View Post
Do you have the thermostat? My thermostat was recently removed and it never crosses 60, in fact it remains firmly at 40-45 while driving in rains. I don't have electric fan either.

How's your water pump?

My Jeep heating problem became so severe at one time, I had to move all the heating related posts to a separate thread, which itself turned out to be 11 pages long. It even gave birth to two more cooling test run threads.

https://www.team-bhp.com/forum/techn...blem-jeep.html
1. Thermostat is not there. Has been removed.
2. Sometimes crossed 80 in rains. But has always overheated on highway runs. Never during the actual OTR.
3. Water pump is fine as of now. You've read my water pump issues earlier on.
4. Am going through your quoted thread

Quote:
Originally Posted by gsferrari View Post
Just to understand this better what you are saying is that your wheel makes 1 full rotation for every 4.88 rotations of the transmission output. As the wheel diameter increases this means you cover more distance with every rotation. Therefore 4.88 rotations is now doing more work than with smaller wheels and therefore the engine is struggling.

So if you increase wheel diameter then it is better to increase the diff-ratio to 5.38 so that instead of 4.88, 5.38 rotations are needed for the same distance which makes it easier on the engine (less torque required and therefore more in store for tackling obstacles).

Do I have this concept sorted out here?
Yes.

Quote:
Originally Posted by The Wolf View Post
Get your injectors cleaned and fuel pump calibrated if its been a while. Feel the injector nozzles with your fingers for any back/abnormal pulse.
Change the clutch. It may be new but sometimes water entry and heavy OTR'ing may prematurely destroy your clutch.
Check all grease points especially star joints.
Jack up your jeep in neutral and check if all the tyres are rotating freely.
LBNTL, check the oil pressure, anything under 3bar isnt great.

For a swb- XDP 4.90 with 4.88 DR should fairly take you anywhere without too much pain plus manage a 100kmph on the speedo on highways.

5.38 will help a bit but your tyres have nothing to do with your overheating.
Everything was checked. It's elementary my dear Watson.

The car goes very freely on the hghway with good acceleration. It's the fact that it starts heating up fast as well.

I never said that 5.38 and overheating are related.

Overheating is one issue. And the other issue i'm facing is that the engine & 4.88 combo can't take the 31"ers during offroading. I'm getting a serious drop in power.

Last edited by Tejas@perioimpl : 24th August 2010 at 11:25. Reason: typos
Tejas@perioimpl is offline   Reply With Quote
Old 24th August 2010, 11:40   #327
Team-BHP Support
 
Samurai's Avatar
 
Join Date: Jan 2005
Location: B'lore-Manipal
Posts: 22,042
Thanked: 13,488 Times
Default

Quote:
Originally Posted by Tejas@perioimpl View Post
1. Thermostat is not there. Has been removed.
2. Sometimes crossed 80 in rains. But has always overheated on highway runs. Never during the actual OTR.
Hitting 80 in rains without thermostat and with electric fan? There is definitely a major issue here.

Keep the radiator cap open and start the engine, do you see bubbles in the radiator water?

Quote:
Originally Posted by The Wolf View Post
Change the clutch. It may be new but sometimes water entry and heavy OTR'ing may prematurely destroy your clutch.
Is this true? Jeepers never do half-clutching in offroading, why should clutch go bad in offroading?
Samurai is offline   Reply With Quote
Old 24th August 2010, 11:46   #328
Distinguished - BHPian
 
Tejas@perioimpl's Avatar
 
Join Date: Sep 2008
Location: Bombay
Posts: 3,947
Thanked: 4,765 Times
Default

Quote:
Originally Posted by Samurai View Post
Hitting 80 in rains without thermostat and with electric fan? There is definitely a major issue here.

Keep the radiator cap open and start the engine, do you see bubbles in the radiator water?
Checked that. Even BD did all that checking a few months ago. No issues and thus ruled out gasket issue. However he did recommend a degassing tank. That though will not solve the overheating issue, will just be a good preventive measure against gas buildup.
Tejas@perioimpl is offline   Reply With Quote
Old 24th August 2010, 14:22   #329
BHPian
 
Join Date: Dec 2009
Location: mumbai
Posts: 193
Thanked: 97 Times
Default

@tejas i just checked with rajeev my DR is 4.27 !!\
so it should do much much more than 60 on the expressway right ?
garrett_t16 is offline   Reply With Quote
Old 24th August 2010, 14:38   #330
Distinguished - BHPian
 
Tejas@perioimpl's Avatar
 
Join Date: Sep 2008
Location: Bombay
Posts: 3,947
Thanked: 4,765 Times
Default

Quote:
Originally Posted by garrett_t16 View Post
@tejas i just checked with rajeev my DR is 4.27 !!\
so it should do much much more than 60 on the expressway right ?
Yup, easily. Hell, your XD3P with 4.27 has more power than my XDP with 4.88! Time to put on my thinking hat...
Tejas@perioimpl is offline   Reply With Quote
Reply


Thread Tools Search this Thread
Search this Thread:

Advanced Search


Similar Threads
Thread Thread Starter Forum Replies Last Post
Never thought I'd buy a Mahindra Thar! My Jeep Story. EDIT: Now sold manveet 4x4 Vehicles 591 14th August 2017 18:18
Scoop: Updated Tata Safari Storme in the offing? EDIT: Now launched Aditya The Indian Car Scene 938 18th June 2015 22:53
EXO Mahape OTR- An Impulsive Outing At A Classic Location genesis 4x4 Excursions 34 2nd October 2010 13:53
Mahindra Classic (To Buy or Not to Buy) Abbas 4x4 Vehicles 26 31st December 2009 13:36


All times are GMT +5.5. The time now is 11:42.

Copyright 2000 - 2017, Team-BHP.com
Proudly powered by E2E Networks