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Old 20th September 2008, 23:32   #16
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Quote:
Originally Posted by GTO View Post
Just because an engine is smaller doesn't mean it will feel any less peppier. Look at the 800! Great to drive in the city....it feels very sprightly from low rpms itself.
That's quite right having driven the 800 and the Matiz for many years. The important thing is the Torque/weight ratio of the car and this at low rpms is lower in case of Civic.

@araje, 800-900 is idle rpm for most petrol cars, so I don't see how you can press the accelerator and the needle is not > 1000rpm almost instantly ? I think you'll get used to the characteristics of your car with a bit more miles with the car :-)

Cheers,
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Old 21st September 2008, 10:27   #17
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You'll just have to get used to it :-). I suffer the same fate with my Aveo 1.4 which is unresponsive (especially with AC on or if fully loaded) below 2000 rpm.

This is especially irritating for example, if you clear a speedbreaker and are still in second gear and try to accelerate or are climbing a steep parking ramp or hairpin turn. My trick is to keep the engine in first gear longer and/or change into first gear (at say 10 or 15 km/hr) BEFORE the speedbreaker of ramp starts.

Now I am used to it!
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Old 21st September 2008, 11:24   #18
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Quote:
Originally Posted by araje View Post
If i let go the clutch fast in an attempt not to drive in this half clutch for those 2-3 seconds, there are serious jerks in the car.
This happens because your engine cannot handle having to move the car so suddenly from a stand still. Don't worry about the 2-3 seconds of half clutch driving. Your friction plate is designed to tolerate that.

You can only get the car rolling smoothly by revving the engine to a comfortable rpm and then letting go of the clutch slowly. Don't worry about wearing out your clutch. It is designed to handle that much friction.

Quote:
Originally Posted by araje View Post
Also, I have noticed that some days there are lots of jerks in the car the moment I take the foot off the accelerator in relatively lower speed bands of the gear, but some days its just real smooth giving a good experience.
As to why this happens, I have no clue.

Quote:
Originally Posted by aerohit View Post
If you thought Civic has less torque, then what about the other smaller cars that people drive everyday ?
Well, these small cars are much much lighter than the Civic. Also, they have smaller wheels. So the engine isn't taxed so much while getting it to start rolling.
But even with these small cars, with the air conditioning running and if you happen to be on even a slight slope, it'll struggle more than you'd expect (here I'm talking about a Maruti 800 with 12 valves, MPFI and a 5 speed gearbox).


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Old 21st September 2008, 21:10   #19
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My Civic starts moving slowly forward with the slow release of clutch and no acceleration on the first gear. This is a very slow movement, which I uses in bumper to bumper traffic.

But if you have slowed down for some reason to a near complete stop and starts to accelerate again in second gear then its required to pump in the accelerator to get the right rpm/power for the car to move forward. This I feel quite sluggish in the beginnig if I have not pumped enough..This needs a getting used to, and a seating position so that the leg on the clutch knows how much to release.

But I have tried from stop, shifted to 1st, revved enough and let go, Civic simply zooms. If have continued, it could have touched the limiter too...I feel pretty much a bit getting used to..Nothing much to worry..
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Old 21st September 2008, 21:31   #20
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Its a petrol, it needs to be revved a bit more. 1k rpm is nowhere near enough for it to produce enough torque.

Quote:
Originally Posted by Thad E Ginathom View Post
Don't know the car, but below 1000rpm is barely idling. I would not expect my Swift to pull away smoothly at 1,000, and low-rev pulling is the speciality of diesel.

Don't worry about the rev counter, drive by feel, and give the car some more revs; it really sounds that that is what it is asking for. Not doing so will stress your engine and clutch.
is OT as its a Civic thread, but,
@Thad
methinks swift diesel should pull at idle in 1st gear without use of the accelerator, it will do so even on pretty serious inclines.
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Old 21st September 2008, 21:41   #21
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OT, yes --- the Swift seems to have something built into its ECU that increases the revs. It is quite difficult to stall! Errr... but not impossible; I have done.
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Old 22nd September 2008, 00:00   #22
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Quote:
Originally Posted by ajinkya View Post
This happens because your engine cannot handle having to move the car so suddenly from a stand still. Don't worry about the 2-3 seconds of half clutch driving. Your friction plate is designed to tolerate that. You can only get the car rolling smoothly by revving the engine to a comfortable rpm and then letting go of the clutch slowly. Don't worry about wearing out your clutch. It is designed to handle that much friction.
Thanks ajinkya.. This is exactly what I was concerned with. Thanks for clearing it up.

Quote:
Originally Posted by lancer_rit View Post
800-900 is idle rpm for most petrol cars, so I don't see how you can press the accelerator and the needle is not > 1000rpm almost instantly ?
Actually, I think thats because of the car I learnt on, in driving school. It was a santro and in it I could handle stopgo traffic just by clutch press release. DIdnt even have to touch the acc. Since thats the first car in india I started with, I took that behavoir as a baseline. I guess thats why I was noticing this difference

Quote:
Originally Posted by laluks View Post
My Civic starts moving slowly forward with the slow release of clutch and no acceleration on the first gear.
True, but if I rely on that, some one easily comes inbtw me.. U know how bangalore traffic works . So this speed is simply not sufficient.

Quote:
Originally Posted by laluks View Post
But if you have slowed down for some reason to a near complete stop and starts to accelerate again in second gear then its required to pump in the accelerator to get the right rpm/power for the car to move forward. This I feel quite sluggish in the beginnig if I have not pumped enough..
Completely agree with you... the car starts showing mild vibrations on 2nd gear at 9-10km/h and thats when I have to hold the clutch back again. But I really want to start from there and not go back to 1st at times. Thats where I need to rev it and slowly release the clutch.. but still it goes sluggish for few secs and after that all the power comes in.... thats where it gets interesting

So in all I have to get used to this in traffic, I guess. But near the other end of the tacho, the car is like butter.
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Old 22nd September 2008, 01:48   #23
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Quote:
the car starts showing mild vibrations on 2nd gear at 9-10km/h and thats when I have to hold the clutch back again. But I really want to start from there and not go back to 1st at times.
That's a mistake: you should go back to 1st. You should not be using clutch control in 2nd. You should never let the engine judder because the gear is too high; the clutch is not there to compensate for this.

That is a lesson from one of my UK driving instructors, correcting my actions at the time.

When you have been driving a while, you'll learn what liberties you can take, and where and when you can throw the rule book away, but while you're a new driver (say the first two years, which includes the building confidence and phases of over-confidence) try to drive by the book. You'll be a better and safer driver for it, and your car maintenance bills will be lower.
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Old 22nd September 2008, 10:23   #24
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i also faced the similar problem when i switched over from diesel innova to petrol altis especially on hills (in philippines). changed my driving style and it was ok.

another experience of mine on new car is about idling rpm. 50~100 odd rpm less is difficult to notice on tachometer but makes a hell lot of difference in driving experience.
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Old 22nd September 2008, 11:14   #25
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One slightly off but related topic : why are clutches so hard?
I mean since everyone knows that in city you are supposed to use half/quarter/ whatever clutch for quite some time - why not have a softer version of clutch?
The one that doesnt make you feel like pressing a leg press machine instead of releasing/engaging the clutch.
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Old 23rd September 2008, 19:23   #26
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Whoops! Missed the discussion on this thread.

Quote:
But if you have slowed down for some reason to a near complete stop and starts to accelerate again in second gear then its required to pump in the accelerator to get the right rpm/power for the car to move forward.
I always prefer to move back to first gear. In most petrols, you will have to slip the clutch to get moving from 2nd gear. Not a good thing.

Quote:
Originally Posted by viper View Post
The pipe diameter is in fact larger than the stock...
Viper, again, larger dia pipes will always move the torque higher up. Thats not me talking, it's physics. I simply cannot see how such an exhaust will result in improved driveability. A free-flow exhaust does not necessarily have to be implemented with bigger pipes.

[quote[Remember the catalytic converter is removed and the muffler design is less restrictive which is what improves the performance. Viper[/quote]

I am certain it improves performance, but that's mid-range / top-end performance.
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Old 23rd September 2008, 20:05   #27
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If I may chip in my 2 cents: -

With all due respect, if pipe dia is increased the amount of torque will definitely reduce.

In this case, increase in torque felt inspite of increasing the dia is primarily due to the fact that the CAT converter has been removed. Effectively what has now happened is that the dia of the pipe is reduced due to removal of the CAT con.

Also in the case of a civic a free flow exhaust is not like the conventional 4-2-1 or 4-1 type, because of the basic construction of the engine. The manifold is inbuilt into the head and therefore only a single pipe can be fitted.

I think the problem in this case is due to adulterated fuel being used or it just might be due to the fact that araje is not used to the characterisitics of the car.

Araje, don't loose sleep over it.

Cheers.

Last edited by Sideways : 23rd September 2008 at 20:10.
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Old 24th September 2008, 01:26   #28
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I bigger diameter header will reduce low end torque but the torque curve at higher rpms will get stronger. Increase in pipe diameter further reduces exhaust flow velocity at lower revvs which causes a drop in low end torque.

Heres a test conducted on an engine comparing 2 diff pipe diameters. the first one had a dia of 1 5/8" while the 2nd header had a 1 3/4" pipe (everything else being identical). And this is what the dyno results showed.

The Baseline In previous tests we used a borrowed set of headers because NTI had them handy and they fit the dyno. We're not even sure of the brand, but they used a 15/8-inch primary with no steps. Using those headers with Comp's Pro Magnum rockers (the same used throughout these tests), peak power was 401.7 lb-ft of torque at 4,600 rpm and 401.1 hp at 5,700 rpm. Since our last test, NTI had also recalibrated its dyno and pulling back up the old tests with the new calibration, the peak numbers for both horsepower and torque increased by two (403.7 and 403.1, respectively).

After giving Doug Schoenfeld our engine's specifics, he chose a larger, 13/4-inch primary tube for our headers, and the choice was a good one. Our new baseline headers dropped a bit in peak torque with 386.1 at 4,600 rpm, but it significantly opened up the torque curve. Torque stayed higher in the upper rpm ranges which bumped peak horsepower up to 416.4 at 5,900 rpm. An improvement of 13.3 ponies!


So the bigger dia pipes reduced peak torque by 4% but the peak hp increased by 4%.

Source (see bottom of page) - The Header Test - Engine - Third Test - Circle Track Magazine

PS : Ive driven 3 diff Civics in stop n go traffic but never experienced any probs to such an extent (as mentioned by Araje). It has to be something else causing this prob.

Shan2nu

Last edited by Shan2nu : 24th September 2008 at 01:33.
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Old 24th September 2008, 01:28   #29
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You guys are confusing header diameter and exhaust diameter. Header diameter remains the same on the Civic and it is only the final exhaust piping that is changing. Removing the standard muffler arrangement may make the car peppier, and adding an aftermarket filter will also have the same effect. I don't think torque is increasing significantly. Acceleration is increasing though, and I'm quite sure if you put it on a dyno, you will see an increase in whp just because the engine is able to rev quicker and more freely.
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Old 24th September 2008, 10:24   #30
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I second sideways & shan2nu's post.

Quote:
Quote:
Originally Posted by Shan2nu
PS : Ive driven 3 diff Civics in stop n go traffic but never experienced any probs to such an extent (as mentioned by Araje). It has to be something else causing this prob.

Shan2nu


@ Araje (no offence) Are you a new driver by any chance? how much driving have you done before you got your hands on civic, cause you mentioned about driving school where you practiced on a santro, releasing clutch at 1k rpm without any acceleration when car is at standstill.& you are applying same concept here, those training cars must have raised their idling rpm for trainers purpose, afaik you should always raise the rpm engine slightly when you start your car from standstill. if it was a diesel car than things would have been different.

Your one of the reply in earlier post
Quote:
Originally Posted by araje View Post

Actually, I think thats because of the car I learnt on, in driving school. It was a santro and in it I could handle stopgo traffic just by clutch press release. DIdnt even have to touch the acc. Since thats the first car in india I started with, I took that behavoir as a baseline. I guess thats why I was noticing this difference
As marked in bold, not applicable to all cars.

Last edited by Ford Rocam : 24th September 2008 at 10:32. Reason: added content
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