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Old 19th February 2009, 20:31   #1
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Do you lug your engine?

Friends,

I have noticed that many of my Indian friends tend to lug their engines ate low RPMS in an effort to squeeze out every bit of distance per unit fuel.

I wanted to make a thread to make sure you guys are aware that this is HORRIBLE for your engine.

The short version: DONT DO IT!

The long version:
What is lugging?

There is no clear definition for this since the parameters are different for all cars. For the average gasoline engine, anything below 1750rpm in 3rd or higher hears is lugging. With diesels the RPM range drops to 1250rpm or so.

When in gear, if you accelerate and the car is unable to accelerate - that is lugging.

If you hear gurgling, grinding or other noises that reduce when the RPMS increase - thats lugging.

What does lugging do?
Lugging means the engine is unable to push down on the pistons because of unrealistically high load placed. This can lead to incomplete combustion, increased emissions, WORSE mileage, detonation and carbon deposits in your engine.
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Old 19th February 2009, 20:40   #2
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Quote:
Originally Posted by Atlblkz06 View Post
What is lugging?

If you hear gurgling, grinding or other noises that reduce when the RPMS increase - thats lugging.
Almost the same as being in too high a gear at too low a speed!
That's how it is best understood here!

You're quite right about your observation that a lot of Indians believe that the lower the engine rpm, the better the FE! Gears seem to have no place in all of this!
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Old 19th February 2009, 20:59   #3
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Wrong site I think

Make another thread asking if people redline their engine. Will find more takers I think.
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Old 19th February 2009, 21:04   #4
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Originally Posted by pranavt View Post
Wrong site I think

Make another thread asking if people redline their engine. Will find more takers I think.
Somehow, I think his friends are not members here at T-BHP!
Is there no merit in what he's saying?
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Old 19th February 2009, 21:15   #5
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Quote:
Originally Posted by Atlblkz06 View Post
Friends,

I have noticed that many of my Indian friends tend to lug their engines ate low RPMS in an effort to squeeze out every bit of distance per unit fuel.

I wanted to make a thread to make sure you guys are aware that this is HORRIBLE for your engine.

The short version: DONT DO IT!

The long version:
What is lugging?

There is no clear definition for this since the parameters are different for all cars. For the average gasoline engine, anything below 1750rpm in 3rd or higher hears is lugging. With diesels the RPM range drops to 1250rpm or so.

When in gear, if you accelerate and the car is unable to accelerate - that is lugging.

If you hear gurgling, grinding or other noises that reduce when the RPMS increase - thats lugging.

What does lugging do?
Lugging means the engine is unable to push down on the pistons because of unrealistically high load placed. This can lead to incomplete combustion, increased emissions, WORSE mileage, detonation and carbon deposits in your engine.
Absolutely 100% Correct! It gets on my nerves when ppl do this! Its either drive in a low rpm zone or rip. Anyone heard of 2-3000rmp power bands in diesels? Apparently not.
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Old 19th February 2009, 21:32   #6
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There is no specific rpm for lugging.

A car doing 1500rpm in 3rd going uphill with full load will obviously come under a lot of stress compared to the same car doing 1500rpm in 3rd going downhill (or even on a flat surface) without any passengers.

So instead of sticking to fixed rpm figures, improvise your gear shifts wrt diff load conditions.

Shan2nu
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Old 19th February 2009, 21:59   #7
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While extremes are never recommended, the manufacturer recommended gear shifts are perfectly doable at the same time. I've heard many people ask how it is possible to drive in 5th gear at 45 kmph (as an example) simply because Maruti says so in their manual. It is possible if you know how and dont overdo it.
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Old 19th February 2009, 22:01   #8
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Quote:
Originally Posted by Shan2nu View Post
A car doing 1500rpm in 3rd going uphill with full load will obviously come under a lot of stress compared to the same car doing 1500rpm in 3rd going downhill (or even on a flat surface) without any passengers.
Implicit in this is the fact that uphill and downhill is being done in the same gear! That is recommended practice.
The ones who lug their car engines are unlikely to follow this rule of thumb! They'll most likely turn off the engine on downhill sections! FE, remember?!
Or at least coast in neutral! And after a while, brakes ... what brakes?!!
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Old 20th February 2009, 02:00   #9
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Quote:
Originally Posted by pranavt View Post
Wrong site I think

Make another thread asking if people redline their engine. Will find more takers I think.
LOL - I do both!

No, not really lugging, but i stick to low revs in city crawls when the torque is not really needed. I hate stalling so I do not lug.

Cheers,
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Old 20th February 2009, 02:36   #10
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Just for the record, it is called 'labouring' in British English --- not that that matters a great deal to Indian drivers!

As to that 2,000-3,000 diesel power band, I've noticed recently how comfortable my Swift VDI is, maintaining a constant speed, on the flat, at around One thousand RPM --- and yes, it'll pick up without complaining if I give acceleration.
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Old 20th February 2009, 03:09   #11
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Do you lug your engine?

The first thing you need to know is that it's easier to KEEP a car moving than it is to GET a car moving.
In other words, getting a car from 0 kmph to 50 kmph takes a lot more effort than keeping it going at 50 once it's already there.

The gears in a car are designed for various degrees of difficulty.

First gear, for instance, is designed for the hardest work, when you're moving a car from a dead stop or climbing a steep hill. In first gear, the engine's crankshaft may turn 100 times for every rotation of the wheels.

The car's fifth gear is designed for the easiest duty, when you're already at speed and just need enough power to keep the car moving at that speed. So in fifth gear the engine just lopes along, turning the crankshaft only, say, 25 times for every rotation of the wheels. And that saves gas!!

So, when should you use fifth gear? As often as possible – as long as you're not lugging the engine.

Lugging, means that the engine is struggling to accelerate. How would you know it's struggling? Because when you step on the gas to accelerate, it doesn't go faster. It might bog down, it might buck, it might lurch. And you might get noises from the engine, like pinging or knocking. If any of those things are happening, you're going too slowly to be in fifth gear, and you need to downshift.
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Old 20th February 2009, 03:22   #12
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Quote:
Originally Posted by anupmathur View Post

You're quite right about your observation that a lot of Indians believe that the lower the engine rpm, the better the FE! Gears seem to have no place in all of this!

actually lower the rpm, higher the mileage is correct factually, as long as it's done in tolerable limits.

it's bad for car or environment is a different issue altogether.

EDIT: in my automatic nissan quest, the V6 runs below 2K when cruising at 65 mph on highway on overdrive.

Last edited by vivekiny2k : 20th February 2009 at 03:24.
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Old 20th February 2009, 03:27   #13
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Ever seen new drivers(usually women).
Revving their cars in 1st and 2nd gears to avoid shifts
wonder what is it called?
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Old 20th February 2009, 03:53   #14
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On the contrary, lugging is perfectly fine for diesels.

Everyone and their tommy crawls in first gear using the low end torque.

What am I missing here?
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Old 20th February 2009, 06:07   #15
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I wonder if I lug my engine. I can leave it in third or even 4th at idle and crawl around in the city without jerking/shuddering/knocking, and the car picks up faster than most other vehicles on the road when the accelerator is depressed from that rpm.

theoretically, that increases the load on the mechanical components right?
but, considering that it accelerates with ease from idle in 3rd, it it really lugging?

Driving above 1700rpm in 2nd or 3rd in the city traffic is slightly difficult, because the car will be considerably faster than the surrounding traffic.
You can forget about 4th
 
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