[sreerajunnithan]

Dear All,

This is not just a doubt clearance question. I am planning to drive to Himalayas next year. Yes, you guessed it right - In my Jeep. I was discussing the same to lot of experts who had been there and done that. Some vouch for the Jeep, and some do not (Even the Jeep owners). This expedition was always my dream, and it really depends on all of your views that which vehicle i will opt for the same. Being a Jeep owner, i prefer to complete this in My Jeep. Don't discuses about any Plans/Routes for the travel as i haven't decided on that.

So, how bad would be a NA engine's performance on High Altitude, considering the lack of Oxygen? Mind you, i am not just planning till Leh, But even to Kardungla Pass. Some vouch for TC engines but, TC settings are not dynamic, less air means less intake pressure, so do you think that TC will work better? Then comes, TCIC with DI, i do not know any advantages of a DI over an IDI on high altitude, or does it have any advantages at all? I know MPFI and CRDe will be the ideal solution, for this, i Need to wait for Thar or Purchase a Brand new Gypsy. I wouldn't mind buying a new Gypsy for this - Now you know how important this dream is for me. But is it the final solution? Don't you think i should take this as a last step? (Purchasing A Gypsy) I love my Jeep and i don't want to get rid of that unless Behram sir is giving me a Thar within my budget .

I know its challenging, i myself has advised someone to go for a Gypsy for such kind of use. And i developed a respect over Gypsies over a period of time, by witnessing it's performance and reliability over various OTRs and long drives (Ex. Siddu's 20 years old MG410). But at last, "It's a Jeep Thing" So please pour in your views on this.

1) How Bad is a NA engine on High Altitude?
2) Is it so bad that we can't drive it there?
3) Any kind of Pump tuning will do the Job once we are there?

As i told you, it's not an attempt to learn the technology, but my choice of vehicle for this expedition depends on your opinions.

PS: Jeep will undergo a Rigorous Overhauling before this (Read, Suspension, Engine, Brakes et all) Though my engine is good for another 50k KMs.
PPS: Kardugla Pass is an Off-Road Drive, Hence posted in this section.

Thanks
--Sree--

[vinod_nookala]

Sree,
Great to see that you want to do every bit of it to realise your dream. Long back silk route was conquered by Armada 4wds and i still remember the report saying they had to use low ratio to climb graditents as engines ran out of power.

But then this brings meto the question-

1. How does Qualis and Sumo NA manage to do laddak and leh journeys?
2. How does Army compensate for loss of power in high altitudes?

Iam sure turbo charging is not the only answer. I remember some one telling me Qualis had some special thing in its engine which adjusted to oxygen availability on high altitudes, dont know what that exactly is.

When Army jeeps can do it your jeep too can do it as yours in a 2.5 litre engine.

Doing high altitudes in a Gypsy is no fun, its boringly reliable. Do it in your jeep and your cost will also be less.

[sreerajunnithan]

Great to see that you want to do every bit of it to realise your dream.

Thanks Vinod.

1. How does Qualis and Sumo NA manage to do laddak and leh journeys?

Even i thought the same thing. But did not find any valid reasons
But Leh and Laddak is no a big deal. We are talking about even higher altitudes like Kardungla

2. How does Army compensate for loss of power in high altitudes?

Those vehicles run there regularly, so may be FIP is optimized for Air/Diesel Mixture? I could be wrong here.

I remember some one telling me Qualis had some special thing in its engine which adjusted to oxygen availability on high altitudes, dont know what that exactly is.

Even i heard something similar to this. In modern CRDe motors it could be possible, but i do not know how this is practical in conventional NA engines.

When Army jeeps can do it your jeep too can do it as yours in a 2.5 litre engine.

Read my comments about permanent FIP tuning, i may wrong though.

its boringly reliable.

lol!!! I like this term, "Boringly Reliable"

Thanks
--Sree--

[Shan2nu]

1) How Bad is a NA engine on High Altitude?

Although altitude affects outright performance, it doesn't really make much of a diff, if you just wanna drive around.

Leh is around 10,500ft above sea level. Even if we consider 3% loss in power per 1000ft. You should still have close to 68-70% of the engine's power/torque at sea level (which is more than enough).

Shan2nu

[r@CYR@y]

Originally Posted by sreerajunnithan

1) How Bad is a NA engine on High Altitude?
2) Is it so bad that we can't drive it there?

Leh is at an altitude of 3,500 meters (11,483 ft).

Theory:

The atmospheric pressure will be atleast 25% lesser than at MSL.
And we know that oxygen content is only 21% in the atmosphere at the sea level, 25% drop in pressure means 25% less oxygen, lesser oxygen lesser will be the power, If you are going there for a short trip then there is no need to do any modification to the engine except the carb, lower the air/fuel ratio by re-jetting or tuning..

If you dont change the fuel ratio, the excess fuel may damage your catalytic converter (Assuming that its still working)..

To give you a general idea how worse atmospheric pressure change is, have a look yourself..

This plastic bottle, sealed at approximately 2,000 m (6,600 ft) altitude, was crushed by the increase in atmospheric pressure when brought to sea level.

Practical:

Just have a look at the pic below,

Its Leh..

See the number of vehicles in there, do you think every car has been tuned to run on those roads?



Keep revving...

[tsk1979]

While you will not need any specific tuning, expect some missing and definite loss of power.
The highest I took my NA indica to was around 3100meters above sea level, and there was a noticeable power loss.
Nothing killer, but it was there.
Other than that there was occasional missing, and of course, lots of black smoke. Infact if you notice, while climbing inclines, most Qualis and Sumos(extremely popular up there) produce a lot of black smoke. Even turbos have this problem, but its less as compared to NA..

Now places like Khardungla as well over 5000 meters above sea level, and both DI(Tata Spacio), and IDI(Tata Sumo) run there without issues. There are a few old indica's also I saw up there.
while a TC engine will be better(less loss of power), its not a deal breaker. Just make sure the cooling system is very sound. Overheating will be an issue. I know it sounds weird to have overheating in a cold desert, but day temperatures hover around 20 degree C+, and when you are climbing in first gear for long intervals, you will have the cooling system on overdrive.

Also make sure that you chance oil just before going.
If you park your jeep at a cold place, when you start next morning, idle her for few minutes to get the engine oil warmed up before marching.

[sreerajunnithan]

Originally Posted by r@CYR@y

See the number of vehicles in there, do you think every car has been tuned to run on those roads?
Keep revving...

Damn!!! Not even one Diesel vehicle up there (In the picture) !!! I am more scared now

Originally Posted by tsk1979

While you will not need any specific tuning, expect some missing and definite loss of power.
The highest I took my NA indica to was around 3100meters above sea level, and there was a noticeable power loss.
Nothing killer, but it was there.
Other than that there was occasional missing, and of course, lots of black smoke. Infact if you notice, while climbing inclines, most Qualis and Sumos(extremely popular up there) produce a lot of black smoke. Even turbos have this problem, but its less as compared to NA..

Now places like Khardungla as well over 5000 meters above sea level, and both DI(Tata Spacio), and IDI(Tata Sumo) run there without issues. There are a few old indica's also I saw up there.
while a TC engine will be better(less loss of power), its not a deal breaker. Just make sure the cooling system is very sound. Overheating will be an issue. I know it sounds weird to have overheating in a cold desert, but day temperatures hover around 20 degree C+, and when you are climbing in first gear for long intervals, you will have the cooling system on overdrive.

Also make sure that you chance oil just before going.
If you park your jeep at a cold place, when you start next morning, idle her for few minutes to get the engine oil warmed up before marching.

Thank you Tanveer, it is nice to hear about NA Sumos up there on Khardungla. And i know you have have been there and done that, so this is a valuable advice!!!

Thanks
--Sree--

[Jaggu]

I think its very much doable, just ensure the vehicle is in top condition and do a complete check and oil change just before you start the climb. It will smoke and some amount of power loss will be there but it will do the climb. You might want to invest in some antifreeze for diesel tank and radiator if its going to be done in peak winter.

I would be more scared about the soft top without a heater more than the vehicle if the above mentioned is adhered to

[sreerajunnithan]

I think its very much doable, just ensure the vehicle is in top condition

Yes, i will make sure this is taken care, hence going for a complete work before this

You might want to invest in some antifreeze for diesel tank and radiator if its going to be done in peak winter.

No plans do it in Peak winter, the road is open after May15th i guess, However, would be interested to know the details about this.

I would be more scared about the soft top without a heater more than the vehicle if the above mentioned is adhered to

he he he! look at this http://www.team-bhp.com/forum/4x4-te...ml#post1573796

The whole idea was this trip. Having said that, I think Viji and Shakir went there in a soft top Gypsy, and they told its not a concern. I do not know if they used Heater though.

Thanks
--Sree--

[starter]

Hey Sree,
I've been to Himachal & Leh including K'la twice in the last 1.5 years.
Once we did it in a Scorpio 2.6 & once in a Tavera. I guess, both are TC.
I have seen NA Sumos but they are very few. Not just Sumos, even army 550s are very few, although i spotted about 5 in the entire journey. But, there are definitely diesels running up there. There are loads of Tata TLs. Personal experience, there was a drastic reduction of power in our Tavera while climbing Chang La (Just 4 people and the driver, each averaging 65 kgs) In the process, we also faced engine over-heating. Of course, keeping in mind, it was a taxi and not well maintained. Your 550 can definitely do it, but i personally would prefer to go there in a convoy.
Would love to know if you are planning it next year.
Cheers,
Deepak

[swastikviji]

Originally Posted by sreerajunnithan

Damn!!! Not even one Diesel vehicle up there (In the picture) !!! I am more scared now

Hi Sree,
Thats What i told you, i have seen plenty of TATA twin cabs, and Toyota Innova Tourist cabs. not a single civilian MM 540, Why Don't you buy a stallion for this Expedition, i am damn Sure it Goes,

[khan_sultan]

Hey Sree,

Don't bother about all this. Take my Gypsy and go. You pay the fuel bill and I will be your designated driver :-)

Cheers,

[star_aqua]

Dont worry pa! get the engine done up and make sure the compression is good. petrol engines need tuning at every altitude as it changes. diesels can tollerate the changes in AFR. only thing you see is black smoke but they can make it with reduction in power. since our jeeps are blessed with "4L" and hub locks, it can compensate for power loss. you have tune the FIP to run lean to reduce smoke which will only result in reducing only smoke but not gaining any power. how about a electric turbo? which can be used on demand. can make difference in starting the engine at higher altitude.
get a flat roof hard top. and a carriage on it, just like those camel trophy LRs. have a high CCA rating battery installed. engine oil which is suitable for cold regions. dont use 20-40w there. and how about heaters for oil sump which can be fixed through drain bolt. can get it done here in bangalore.

@K_S: shall we go next september? i will pay for the fuel bill till we reach MarsmikLa.

[DHABHAR.BEHRAM]

Dear Sree - the trick is to maintain "required" air fuel ratio. As air is going to be less, you have to reduce the fuel injected. Power delivered at the flywheel will of course reduce. I presume your vehicle is an MM540. Please let me have details of the engine, is it XDP4.90 / XD3P? I would also like to have the transmission / axle ratios and the tyre size. I can then guide you on steps to be taken to recalibrate your fuel system to operate your engine on high altitude. I will have to gather this information so please give me some time.

Dear Shahnawaz - Hello after a long time. I like the caption at the bottom of your above thread. How true you are! I get affected by it daily. Jai Ho!

Best regards,

Behram Dhabhar

[swastikviji]

Originally Posted by khan_sultan

Hey Sree,

Don't bother about all this. Take my Gypsy and go. You pay the fuel bill and I will be your designated driver :-)

Cheers,

This is not fair, he agreed yesterday night that he takes me along with my gypsy, and he promised me that he only drives my gypsy.

Originally Posted by star_aqua

Dont worry pa! get the engine done up and make s how about heaters for oil sump which can be fixed through drain bolt. can get it done here in bangalore.

But it takes Years to do it, The Manufacturer always Busy.