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View Poll Results: Is above 4k rpm useless for regular driving?
Agree 76 54.68%
Disgree 22 15.83%
Depends on the situation 39 28.06%
Dont know 2 1.44%
Voters: 139. You may not vote on this poll

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Old 15th March 2011, 12:52   #46
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Default Re: Debate: >4k rpm band useless for regular driving and for regular joe drivers

Fun starts after 4500 rpm. Only place where I rev lower than 3000 rpm is when the car is at standstill and I don't want wheelspins. My Honda gives me better mileage when I keep it at around 4500 rpm mainly due to my ITBs and fuel atomisation characteristics.
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Old 15th March 2011, 13:43   #47
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Default Re: Debate: >4k rpm band useless for regular driving and for regular joe drivers

my car likes to be revved and I rev it everyday above 4000 rpm..that is where the real fun is.
I drive totally in the city and have never done a major trip outside in my Jazz.
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Old 15th March 2011, 13:55   #48
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Default Re: Debate: >4k rpm band useless for regular driving and for regular joe drivers

I feel i am not doing justice to my car if i keep the revvs below 3500 rpm.
And when i am in a car that labors to go beyond 4K rpm, i feel justice is not being done to me.
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Old 15th March 2011, 13:58   #49
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Default Re: Debate: >4k rpm band useless for regular driving and for regular joe drivers

In town you will need 4000 rpm (of course all discussion is for petrol engines) only if running away in a hurry. On the highway you may need to use it for acceleration, or occasionally for three digit speeds. I may add that I have never had need to kick in the VTeC into the high rpm mode in my Civic, except to test it out once or twice. However, my son managed to make use of it a few times on the NH2.
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Old 15th March 2011, 14:08   #50
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Default Re: Debate: >4k rpm band useless for regular driving and for regular joe drivers

Agree with the topic being diesel vehicle owner.

My observation about comfortable drivng is between 2500 and 3000 RPM. Being diesel I get the torque benefit.

On expressways I have tried 3500 to 4000 rpm, however cannot try that in city driving.

Earlier experiences with petrol, more the RPM, more the fun.
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Old 15th March 2011, 17:48   #51
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Default Re: Debate: >4k rpm band useless for regular driving and for regular joe drivers

Nice thread!

I have myself seldom strayed on the other side of 4k. In the cities, I upshift between 2.5-3k. On the highways, I generally do not exceed 100 km/hr so going 4k + becomes rare. It is mostly while overtaking that I downshift and go past 4k.

Now, here's what I'd like to know. Keeping FE as the 2nd priority, is it good for the engine to be revved up to at least 4k during upshifts - all this on the highway of course.

I had once gone for a drive with a friend who went up to 5-5.5k on each gear and then upshifted. Does this occassional revving up help the engine perform optimally on that drive?

Also, is it necessary that higher rpm would translate into higher torque all the time? If yes, then one would want that power only when one has the road to use it on, right?

An afterthought : Even on the highway, most of the people are in no hurry. So, they would rather upshift at 2.5k and drive sedately rather than wait till at least 4k on each gear and feel the power.

Is this more because of our perception of FE being paramount? Maybe so.
How healthy is it for the engine to be revved regularly around 4k?
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Old 15th March 2011, 17:49   #52
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Default Re: Debate: >4k rpm band useless for regular driving and for regular joe drivers

Nice thread, managed to get me out of hibernation

I feel that a big big BIG advantage of high revving is the improved engine braking characteristics. When you are >3K rpm you will have more control and less of the typical brakelight dance we see on the roads. This applies in many situations (e.g. descending a flyover, roundabouts, wide city roads with fast-moving traffic etc.). I realize this because on a number of occasions, when friends and relatives have followed me in another car they always ask "How is it that your brakelights rarely light up? We had to keep accelerating and braking to stay with you!". The secret is simply to drive a few rpm higher

Another point - a lot of our eco-cars have poor NVH characteristics, which results in resonating booms when we rev high. This is a big deterrent for a number of drivers. Try revving a D-Segment automatic and the difference between sports mode and "D" needs to be experienced to be believed. You get a throaty snarl with none of the accompanying resonance - and far better performance.

Lastly, I am not sure if there is a very strong relationship between revs and FE - I have found that my city FE depends more on the route I take and less on how much I rev (within sane limits).
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Old 15th March 2011, 18:47   #53
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Default Re: Debate: >4k rpm band useless for regular driving and for regular joe drivers

When i got my OHC Vtec, i redlined several times during the night drives in the city however in city traffic conditions the power band below 4K is what comes into play.

Further to this, last week i had disconnected the battery for a week (due to some reasons) and then drove the car in traffic conditions. After a couple of days, i revved it up but found that the car was acting lazy. Now what settings does the ECU pickup after a reset?
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Old 15th March 2011, 22:02   #54
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Default Re: Debate: >4k rpm band useless for regular driving and for regular joe drivers

Quote:
Originally Posted by Carmageddon View Post
Another point - a lot of our eco-cars have poor NVH characteristics, which results in resonating booms when we rev high. This is a big deterrent for a number of drivers. Try revving a D-Segment automatic and the difference between sports mode and "D" needs to be experienced to be believed. You get a throaty snarl with none of the accompanying resonance - and far better performance.
Well said, this is absolutely true. Driving a 1.2-1.4L at high rpm is a matter of courage since they sound as if the engine will come off its socket anytime.

Anyways, I searched the net on the intriguing topic: does ECU adapt to driving style. The best answer, I felt, was in TBHP itself. Here is the link

http://www.team-bhp.com/forum/techni...g-style-2.html (How fast ECU learns the driving style?)
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Old 15th March 2011, 22:54   #55
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Default Re: Debate: >4k rpm band useless for regular driving and for regular joe drivers

Nice thread, thanks for all the valuable information you have posted guys.

I have tried the same in my ANHC and seen the FE drop from 17 KMPL to around 14 for a 500 km long trip that I take every fortnight. I guess needless to say that I now try to keep the RPM range well within the 3.5K mark. Nevertheless, got an important lesson via this thread that revving the engine at high RPMs occasionally has its own benefits.

Quote:
Originally Posted by libranof1987 View Post
Nice thread!

Now, here's what I'd like to know. Keeping FE as the 2nd priority, is it good for the engine to be revved up to at least 4k during upshifts - all this on the highway of course.

I had once gone for a drive with a friend who went up to 5-5.5k on each gear and then upshifted. Does this occassional revving up help the engine perform optimally on that drive?

Also, is it necessary that higher rpm would translate into higher torque all the time? If yes, then one would want that power only when one has the road to use it on, right?Is this more because of our perception of FE being paramount? Maybe so.
How healthy is it for the engine to be revved regularly around 4k?
Can someone answer these

Last edited by avisidhu : 15th March 2011 at 23:04.
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Old 15th March 2011, 22:59   #56
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Default Re: Debate: >4k rpm band useless for regular driving and for regular joe drivers

Well.I rarely touch 3000rpm during my city drive.I upshift as early as possible.may be around or even less than 2000rpm.
May be i am one of the average regular joe driver.
But the mileage i get for this kind of driving is very good.
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Old 15th March 2011, 23:05   #57
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Default Re: Debate: >4k rpm band useless for regular driving and for regular joe drivers

Quote:
Originally Posted by mayankk View Post
This thread was on my mind, and i tried the 3500-4500 band last night.
As i voted, I agree that its no use.
One-it takes a lot of noise to reach.
I DID learn on a non-tachoe'd car, and do switch by engine noise.
With my current ride, i see that it translated to switching at about 2.5-3.5 k.
Two-It was AWESOME!!Intoxicating!!FE be damned!
The surge, hitting the apparent sweet spot was phenomenal!
But i know that its no use in trafficked, mildly or other wise, roads.
Youre going to keep shifting to keep it there,and may even end up bashing the car..so, no thank you.
Ill keep it for UN-regular drives.

PS:its nice to know its there, though.
Quote:
Originally Posted by mayankk View Post
this is for a petrol fiesta.
Now that you've let the cat out of the bag, your prior post can be understood in the proper context.

One has to experience the bliss of driving a Duratec engine at high revs to understand fully. The more you revv, the more she begs for the throttle to be floored. I've never revved past 5500 rmp however--and if I did, my eyes were not on the meter, but fixed on the road.
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Old 15th March 2011, 23:19   #58
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Default Re: Debate: >4k rpm band useless for regular driving and for regular joe drivers

I accidentally voted for don't know . Thanks to this thread now I understand why my NHC engine has become more responsive after returning from long trip to goa. well, after returning from goa my NHC engine has become responsive. I guess it is because I was revving it hard while doing 100-110kmph at 3.5k - 4k rpm. Normally, In city i am usually bellow 2.8krpm because of high traffic on mumbai roads. So yes, revving hard my patrol engine has made my engine more responsive then before.
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Old 15th March 2011, 23:24   #59
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Default Re: Debate: >4k rpm band useless for regular driving and for regular joe drivers

Quote:
Originally Posted by Max View Post
I accidentally voted for don't know . Thanks to this thread now I understand why my NHC engine has become more responsive after returning from long trip to goa. well, after returning from goa my NHC engine has become responsive. I guess it is because I was revving it hard while doing 100-110kmph at 3.5k - 4k rpm. Normally, In city i am usually bellow 2.8krpm because of high traffic on mumbai roads. So yes, revving hard my patrol engine has made my engine more responsive then before.
Well what needs to be asked is, is that hard enough for an I-Vtech, or does hard revving imply driving above 4K?
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Old 16th March 2011, 00:09   #60
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Default Re: Debate: >4k rpm band useless for regular driving and for regular joe drivers

Quote:
Originally Posted by mallumowgli View Post
If you are straining your engine by shifting up soon, you are not going to have the car with you 'longer'. Lugging the engine means lower engine life. Forget economical sense, it doesnt make any sense to me. Forgive the harsh tone, but it irritates me no end when I find people taking ages to overtake, lugging the engine etc. all in the name of FE. If you love your car, you would not do it.

It is like you have a pet dog. And you starve it, so that you can save some money in buying dog food. Always drive the car in the meat of the rpm range

@Samarth Bhatia - on other thoughts i feel you must have missed a 'don't' in your post. In that case, my post is not for you
I did miss a 'don't' on my thread!
Must have been little sleepy!
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