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Old 7th January 2009, 16:37   #466
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Originally Posted by amitk26 View Post
How do some people get average of 14+ on Safari on highways ?
What is the safe and optimal Tyre pressure to get high fuel efficiency on safari ?

Max I got was 13.5 on highways on GQ while driving at 120 - 130 Kmph ? Tyre pressure 32F / 35 rear

On my recent coorg trip I got 11 on hill driving between 40 ~ 80 Kmph mostly in 2nd and 3ed gear and occasional fourth gear to control better on winding roads with tyre pressure 32F /35 R
and 12.5 in plains at around 120 Kmph+ on SH88 and SH17 with tyre pressure 33/36
oh, need to check tyre pressure. Keep forgetting!

And thats what I got for city drive

I dont think I will ever do this again, was to tough for me.
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Old 7th January 2009, 18:37   #467
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Haha, the way jk chettan drives, it gives the cars following him a clear path to follow. Everyone runs away from the charging bull!
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Old 8th January 2009, 10:04   #468
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Default Clutch Judder after prolonged drive

After a prolonged drive (~ 4-5 hours w/o stops),there's a pronounced clutch judder and the gear shifting (esp. from 1st to 2nd) becomes very hard as well.
My Safari has done ~ 25K running.Any idea,what could be the reason behind this ?
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Old 8th January 2009, 11:52   #469
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Originally Posted by amitk26 View Post
........

How do some people get average of 14+ on Safari on highways ?
What is the safe and optimal Tyre pressure to get high fuel efficiency on safari ?

Max I got was 13.5 on highways on GQ while driving at 120 - 130 Kmph ? Tyre pressure 32F / 35 rear

On my recent coorg trip I got 11 on hill driving between 40 ~ 80 Kmph mostly in 2nd and 3ed gear and occasional fourth gear to control better on winding roads with tyre pressure 32F /35 R
and 12.5 in plains at around 120 Kmph+ on SH88 and SH17 with tyre pressure 33/36
On my recent trip Bangalore-Chandipur(Orissa)-Bangalore in my DICOR 2.2, I got the following FE :

14.0 (blore-naidupet stretch + NH5)
13.2 (NH5 + interior roads)
13.2 (NH5 with bad stretches)
12.9 (NH5 + interior roads)
14.6 (NH5)
13.7 (NH5 + naidupet-blore stretch)

I am currently using Delo-400 engine oil and I always stick to BP normal diesel with System-D additive.

Tyre pressure : 32 F /35 R with all tyres on Nitrogen ( didn't have to refill for the entire trip )

Most of the highway, I was cruising at 80-100 kmph with occasional stretches of 110-120 kmph.

cheers,
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Old 8th January 2009, 12:26   #470
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Originally Posted by rb2399 View Post
After a prolonged drive (~ 4-5 hours w/o stops),there's a pronounced clutch judder and the gear shifting (esp. from 1st to 2nd) becomes very hard as well.
My Safari has done ~ 25K running.Any idea,what could be the reason behind this ?
Strong possibility it could be the Clutch Pressure Plate......
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Old 8th January 2009, 13:16   #471
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Originally Posted by ak-47 View Post
On my recent trip Bangalore-Chandipur(Orissa)-Bangalore in my DICOR 2.2, I got the following FE :

14.0 (blore-naidupet stretch + NH5)
13.2 (NH5 + interior roads)
13.2 (NH5 with bad stretches)
12.9 (NH5 + interior roads)
14.6 (NH5)
13.7 (NH5 + naidupet-blore stretch)

I am currently using Delo-400 engine oil and I always stick to BP normal diesel with System-D additive.

Tyre pressure : 32 F /35 R with all tyres on Nitrogen ( didn't have to refill for the entire trip )

Most of the highway, I was cruising at 80-100 kmph with occasional stretches of 110-120 kmph.

cheers,
I think the difference in FE from what I got lies due to highlighted part above , I am trying to arrive at the best combination of Tyre pressure , RPM , Speed , Tyre , Engine Oil to get best FE. Some people have reported good FE at below 2000 RPM but that can not be true because Turbo is meant to utilize exhaust gases and increase efficiency so any RPM before Turbo kicks in can not give best FE at least theoretically.

EDIT : After prolonged highway drives I touched the tyres/ rims and they do not feel heated up at all.
Can any one tell me if Safari Tyre really gets heated up after prolonged drive at 100 + Speed ?
Or my alloys are doing a really good job of heat dissipation ?

Last edited by amitk26 : 8th January 2009 at 13:23.
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Old 8th January 2009, 13:22   #472
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I've observed that if the temperature knob has been set to extreme right (full hot), without turning on the fan or switching on HVAC *F* button, the air that blows into the car is HOT.

Is this the same in all cars Or is it a problem in mine?

Thanks in advance

Please check the position of air intake, this will happen if you are taking outside air. So when the vehical is moving it takes outside air even if the fan is not switched on.
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Old 8th January 2009, 14:58   #473
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Originally Posted by amitk26 View Post
Some people have reported good FE at below 2000 RPM but that can not be true because Turbo is meant to utilize exhaust gases and increase efficiency so any RPM before Turbo kicks in can not give best FE at least theoretically.
Your belief is slightly flawed.

See, when the turbo spools up, the ECU sends more fuel into the engine to use that extra air. Sure, your exhaust gases are being used to pump more air into the engine. But more fuel is also sent in in equal measures. You cannot run an engine too lean (too much air for the fuel being pumped in) or it'll quite literally melt. Only FSI engines are an anomaly here.

Before your turbo has spooled up and begins to actually make boost, it helps improve FE. This is because the turbo "atomizes" the air which helps you get maximum fuel combustion. The improvement is quite marginal though.

Last edited by ImmortalZ : 8th January 2009 at 15:01.
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Old 8th January 2009, 15:33   #474
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Guys, what is the usual period for changing the Brake Pads on the new 2.2L Dicor ???

Our King has been run for 25K kms and now needs a change is it OK, the cost for changing 4,500/- including the labor charges

Last edited by gowda79 : 8th January 2009 at 15:35.
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Old 8th January 2009, 15:39   #475
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Originally Posted by ImmortalZ View Post
Your belief is slightly flawed.

See, when the turbo spools up, the ECU sends more fuel into the engine to use that extra air. Sure, your exhaust gases are being used to pump more air into the engine. But more fuel is also sent in in equal measures. You cannot run an engine too lean (too much air for the fuel being pumped in) or it'll quite literally melt. Only FSI engines are an anomaly here.

Before your turbo has spooled up and begins to actually make boost, it helps improve FE. This is because the turbo "atomizes" the air which helps you get maximum fuel combustion. The improvement is quite marginal though.
Thanks for nice explanation just one question how lean engine ( less fuel more Air ) can melt engine ? Does this mean that engines are designed in
a way such that full specific heat of diesel is not used in combustion process.

Pardon my ignorance I am not from Automobile or Mechanical Engineering background.
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Old 8th January 2009, 18:26   #476
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Originally Posted by amitk26 View Post
... how lean engine ( less fuel more Air ) can melt engine ? Does this mean that engines are designed in
a way such that full specific heat of diesel is not used in combustion process. ...
Quite the opposite. Engines are designed to extract the maximum from the fuel - it is the materials and the cooling system which are designed for that environment, so that temperature of the surfaces exposed to the flame are kept decently below melting point. This gives rise to the risk of engine seizure when coolant is low or absent. Air-cooled engines are designed to work without the coolant, like in scooters and bikes (and the venerable VW Beetle).
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Old 12th January 2009, 10:23   #477
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Post What is the speedo Error % ?

Guys,

What is the error % int he speedometer in 2.2? Just wanted to know. The other day i did a 165kmph on the speedo while returning from vellore. Had a discussion with a friend who was saying that the actual speed would be less.

--
Ramesh
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Old 12th January 2009, 13:26   #478
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Originally Posted by ram.west View Post
Guys,

What is the error % int he speedometer in 2.2? Just wanted to know. The other day i did a 165kmph on the speedo while returning from vellore. Had a discussion with a friend who was saying that the actual speed would be less.

--
Ramesh
Your friend is correct. During my recent drive (B'lore-Orissa-B'lore), I trace-logged the entire trip with GPS and the Safari 2.2 speedo consistently showed about 5% higher reading than the actual (GPS based). [ my Safari has stock tyres/wheels; so error due to change in tyre/wheel size, is ruled out ]

See the attached speed profile for the B'lore-Vijaywada section where I know I touched close to 125 kmph, but the GPS data has recorded 117 kmph as the max speed.

This is not unique to Safari alone. I remember the road test reports in Autocar India - showing speedo errors in many of the cars, including premium brands.

cheers,
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Old 12th January 2009, 15:15   #479
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Thanks ak for the report. So approximately the 165kmph depicts its 155kmph as said in the manual.

But can the bull do more???

Cheers,
Ramesh
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Old 12th January 2009, 15:40   #480
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Originally Posted by ak-47 View Post

This is not unique to Safari alone. I remember the road test reports in Autocar India - showing speedo errors in many of the cars, including premium brands.

cheers,
This could be deliberate not an error , I once read on the Tyre bible link (link not handy will provide URL if I can find it again ) that manufacturers do it as a precaution to make the driver feel good while keeping the vehicle still under manageable speed so at low speeds the speed is more accurate then at higher speeds.
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