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Old 26th February 2009, 14:30   #106
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Ripper, I agree more or less with what you are saying, but when you try just the OHC alone, I'd say there is a very willing and free revving engine. However, even that one does not sound as happy as it does at 3000-4500!
Heck, at these rpms it is almost 'absent', in that you can barely know it is there, LOL!
Thats bcoz at 3000-4500, the engine has not even reached its power band. If you have to drive any car with performance in mind, you have to keep it in its power band. If you keep thinking about what makes your engine happy, you'l get overtaken by everyone.

Everything in life comes at a price. Theres always a benefit to risk ratio.

Same goes for the human body, if you're someone who pushes his body to the limit on a daily basis, you're bound to wear yourself out, faster than the normal rate. But this doesn't stop people from wanting to be sportsmen and continue doing it for as long as they can.

Aleast, car parts are easier and cheaper to replace. Hehe

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18-20kmpl on highways is way to good dude. is it with the ac on? and howmany people in the car??
Quote:
No AC.
Two ppl only, and keeping the speed below 80 all the times.
In comparison, i got 18.6kmpl from my VTEC (blore - hubli) with A/C, 3 people in the car and speeds between 100-110kmph. The best iv got is 21kmpl without A/C.

Heck, our 2ltr petrol Innova gave us 15kmpl with A/C (80-90kmph) while coming from Mlore to Hubli. We will be doing another trip on the same route this weekend in the Innova, will try maintaining 100kmph this time and see if i can beat 15kmpl.

Shan2nu

Last edited by Rehaan : 26th February 2009 at 15:38. Reason: Posts merged. Please use the MULTIQUOTE button instead of making multiple consecutive posts in the same thread. Thanks.
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Old 26th February 2009, 14:52   #107
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Originally Posted by Shan2nu View Post
Thats bcoz at 3000-4500, the engine has not even reached its power band. If you have to drive any car with performance in mind, you have to keep it in its power band. If you keep thinking about what makes your engine happy, you'l get overtaken by everyone.
Hehe
Of course you're right!
That's why F1 engines last out just the ONE race!

It's about what you want from your car! Different strokes, as they say .....
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Old 26th February 2009, 15:18   #108
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Originally Posted by anupmathur
Guys, no engine that I have driven felt 'happy' at redline! Screaming. Is that the word?
Happy, Screaming etc when used in conjunction with an engine are all terms that can have different definitions for different people. So, let us leave it at that.

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Originally Posted by anupmathur
It may be the maximum allowed by the maker, but there is a difference between the maximum allowed and the ideal recommended.
Literally maybe you have a point. But when the manufacturer of my car (who I believe knows best about it) gives me the option to revv upto 6500rom, but denies me the scope to cross that figure, I would tend to think that there is a valid reason for that. And ofcourse, if you want the recommended ideal values, that is again there in the manual - as MSIL says, hit 5th gear ASAP and at between 40-50kmph. That is also OK to be followed.

Quote:
Originally Posted by anupmathur
However, even that one does not sound as happy as it does at 3000-4500!
Well, thats your definition of happy. Differs from person to person. Those redlining their cars find that note happy. I like it when the engine moves the car smoothly at 1000rpm in 5th gear. Some like it when the engine is straining at low rpms. To each his own.

Quote:
Originally Posted by Shan2nu
our 2ltr petrol Innova gave us 15kmpl with A/C (80-90kmph). will try maintaining 100kmph this time and see if i can beat 15kmpl.
You are ignoring the effect of wind drag which increases with increase in speed. And more the drag, lesser the FE.

Quote:
Originally Posted by anupmathur
It's about what you want from your car! Different strokes, as they say.
Precisely. To each his own. You wanna redline your car, fine. You wanna lug it or even push it from behind, thats also fine. You wanna maintain a balance between redline and lugging, its again fine. A car engine is not a delicate thing that cannot take a decent amount of abuse and definitely not something that will just blow up because you redlined it or lugged it.

Last edited by supremeBaleno : 26th February 2009 at 15:20.
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Old 26th February 2009, 15:40   #109
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To each his own. But the debate here is whether lugging really saves fuel as people generally believe.
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Old 26th February 2009, 16:34   #110
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You are ignoring the effect of wind drag which increases with increase in speed. And more the drag, lesser the FE.
Its never 1 factor that decides fuel consumption. So we can't really say how 100kmph will affect FE as compared to 90kmph unless i give it a shot.

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Of course you're right!
That's why F1 engines last out just the ONE race!
Exactly, F1 engines are built to a point where they are expected to last the minimum number of races allowed by FIA for each engine.

In comparison, production engines are built to last, which requires the rpm limit to be much lower than an F1 car.

PS : If FIA were to say that each engine has to last the whole season, the engine design would change drastically, you wouldn't see F1 cars revving anywhere close to 19,000rpm and bhp figures would be way lower.

Shan2nu

Last edited by Shan2nu : 26th February 2009 at 16:36.
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Old 27th February 2009, 01:23   #111
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The rev limiter cuts of fuel till the car is back to certain 'safe' rpms.
the whole point of the rev limiter should mean that till that point it's safe to rev.
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Old 27th February 2009, 11:10   #112
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Read the manuals guys. It does indicate optimal shifting speeds and generally does say that lugging is not good for the engine. IMO, lugging will not increase FE since ECM compensates by pushing in more fuel / changed timings when under load. Again pedal is to the metal in lugging thus throttle body is wide open = more fuel. I believe Maruti is the only mfr saying shift to 5th gear at 40kmph. Try doing that in the Swift - it is comfortable only in 5th after 55kmph.
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Old 27th February 2009, 12:51   #113
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Quote:
Originally Posted by sandeep108
IMO, lugging will not increase FE since ECM compensates by pushing in more fuel / changed timings when under load. Again pedal is to the metal in lugging thus throttle body is wide open = more fuel.
I think you have got it wrong. Someone who is lugging is actually avoiding the use of the A-pedal. So, A-pedal is not to the metal.

Quote:
Originally Posted by sandeep108
I believe Maruti is the only mfr saying shift to 5th gear at 40kmph. Try doing that in the Swift - it is comfortable only in 5th after 55kmph.
You are right. Does not work for Swift-P atleast. I tried it last week.

With my Baleno, I can be at 40kmph in 5th gear with rpm around 1K and the engine pulls along without any strain. This is not lugging.

But when I attempted the same on our Swift, the engine did not feel comfy. So, I had to downshift to 4th. If I had stayed at 5th gear or if someone drives the Swift at 40kmph in 5th gear inspite of knowing that the engine strains, it is lugging.

One useful takeaway for me from this thread is the knowledge that if someone is puttering along placidly in top gear and needs to suddenly gain speed, slamming on the A-pedal is going to result in fuel being unburned. A bad thing in my opinion because a resource is getting wasted. Better way would be to downshift and increase speed.
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Old 27th February 2009, 13:52   #114
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I think you have got it wrong. Someone who is lugging is actually avoiding the use of the A-pedal. So, A-pedal is not to the metal.
Someone who is avoiding using the a-pedal is not lugging at all. Lugging only happens when you force the engine to acc in a gear/rpm that puts it at leverage disadvantage.

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Old 27th February 2009, 14:13   #115
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Quote:
Originally Posted by Shan2nu View Post
Someone who is avoiding using the a-pedal is not lugging at all. Lugging only happens when you force the engine to acc in a gear/rpm that puts it at leverage disadvantage.

Shan2nu
Now, i'm confused again
This is how I used to drive my swiftD in traffic till I joined this thread.
foot off all pedals,in 3rd or 4th gear, just steering.
When I needed to accelerate, I progressively increase the accelerator input as revs climb, never floored it in low rpms.
Is that lugging?
 
Old 27th February 2009, 14:29   #116
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Now, i'm confused again
This is how I used to drive my swiftD in traffic till I joined this thread.
foot off all pedals,in 3rd or 4th gear, just steering.
When I needed to accelerate, I progressively increase the accelerator input as revs climb, never floored it in low rpms.
Is that lugging?
If your engine is running smoothly without throttle, its not lugging.

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Old 27th February 2009, 14:56   #117
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Quote:
Originally Posted by Shan2nu
Someone who is avoiding using the a-pedal is not lugging at all. Lugging only happens when you force the engine to acc in a gear/rpm that puts it at leverage disadvantage.
Shantanu, you are confusing me also now. And if this is happening after 8 pages, I guess we are back to square-one.

I think the OP is also a cause for this confusion. First it says the following :
Quote:
Originally Posted by Atlblkz06
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. If you hear gurgling, grinding or other noises that reduce when the RPMS increase - thats lugging.
This suggests that driving a car at higher gears at an rpm that seems to strain the engine is lugging. With 'strain the engine' being the key word here, I accept this as lugging. And in such cases, A-pedal is avoided, but still it is lugging, contrary to what you said.

An eg. for the above would be if someone drives the Swift-P at 40kmph in 5th gear. Again A-pedal is not floored, but the engine returns feedback of being strained, which means surefire lugging. So, even though the person is avoiding flooring the A-pedal, he is lugging, which is in contrast to what you said.

This is very different from how rippergeo was driving before he made the mistake of seeing this thread, because engine is not strained at those params. He is not lugging and he is also avoiding the A-pedal.

But then the OP also says the following, which brings the 'accelerate and car unable to accelerate' angle, which is also termed as lugging.
Quote:
Originally Posted by Atlblkz06
When in gear, if you accelerate and the car is unable to accelerate - that is lugging.
Here there is fuel wastage and A-pedal is floored, but the desired effect is not obtained. I don't know if this can be clubbed under lugging, but it sure is not a good thing to do. If this also comes under lugging, then yes, my line in the previous post 'Someone who is lugging is actually avoiding the use of the A-pedal' dont hold good.

Last edited by supremeBaleno : 27th February 2009 at 14:59.
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Old 27th February 2009, 15:06   #118
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Originally Posted by Shan2nu View Post
If your engine is running smoothly without throttle, its not lugging.

Shan2nu
Shan2nu, in my Safari Dicor, I can leave it in 4th gear with my foot OFF the accelerator pedal & it chugs along happily & smoothly. Endless kms (provided I have open road ahead & don't need to brake).

However, if I then press the accelerator & try to pick up quickly, it will protest.

So, was I lugging or not when I was puttering along at 40 kmph in 4th? According to me, I was. According to you, I wasn't?
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Old 27th February 2009, 15:38   #119
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Shan2nu, in my Safari Dicor, I can leave it in 4th gear with my foot OFF the accelerator pedal & it chugs along happily & smoothly. Endless kms (provided I have open road ahead & don't need to brake).

However, if I then press the accelerator & try to pick up quickly, it will protest.

So, was I lugging or not when I was puttering along at 40 kmph in 4th? According to me, I was. According to you, I wasn't?
When you are cruising at 40kmph in 4th with the foot off the acc, your engine is soomth and comfortable bcos it isn't getting overloaded.

But the moment you press the accelerator, you're asking the engine to do something it isn't comfortable with, at that rpm and gear.

Quote:
An eg. for the above would be if someone drives the Swift-P at 40kmph in 5th gear. Again A-pedal is not floored, but the engine returns feedback of being strained, which means surefire lugging. So, even though the person is avoiding flooring the A-pedal, he is lugging, which is in contrast to what you said.
Thats only if the engine shows signs of being strained. But if your car is moving smoothly without throttle, it can't be called lugging.

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Old 27th February 2009, 15:49   #120
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Here are some related definitions of lugging. Hope this will make it more clear.

1. to pull or carry with force or effort: to lug a suitcase upstairs.

2. to pull or tug laboriously.
(of an engine or machine) to jerk, hesitate, or strain: The engine lugs when we climb a steep hill.

3. an act or instance of lugging; a forcible pull; haul.

4. To drag or haul (an object) laboriously.

5.To pull or drag with short jerks.

6.To cause (an engine, for example) to run poorly or hesitate: If you drive too slowly in third gear, you'll lug the engine.

7.To pull something with difficulty; tug.

8.To move along by jerks or as if under a heavy burden.

9.To run poorly or hesitate because of strain. Used of an engine: The motor lugs on hills.

Source : lugging definition | Dictionary.com

Theres a reason why words like forcibly, effortfully, labourously, difficulty etc are being associated with lugging.

When an engine is comfortable and not being overloaded, it doesn't matter what rpm or gear you're in, you're not lugging.

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