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Old 25th November 2008, 22:39   #16
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If any one noticed there is one more interesting journey going on, that is this thread, it has travelled four forums, with three title changes by hands of three mods.. great hi revving thread..

Coming back to my ride, one good thing happened that the noise from brakes has disappeared after last night's heavy driving. It was there even after shocker change through that Toyota campaign.

One question for Civic owners, does the same thing happen with Civic also. (now don't think of lying to me)
Edit: As Akshay says please do not compare both cars as I am only seaking honest information.

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Old 25th November 2008, 22:41   #17
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Quote:
Originally Posted by Ym-enjn View Post
One question for Civic owners, does the same thing happen with Civic also. (now don't think of lying to me)
oh cmon. dont make every thread into a civic vs altis thread. you chose the altis, immortalz chose the civic. leave it at that.
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Old 25th November 2008, 22:48   #18
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The Altis has a very agressive rev limiter. So much so that it limits us from extracting highest potential from the engine.
And the engine is yet to complete the running in period. Although the limit generally shown to owners is 1000 kms, in reality we must care for the engine till atleast two thousand kilometers. And then gradually accelerate more freely in gears till atleast next five hundred kilometers.

In anyone's case the engine should not die down. When our Baleno was not even one thousand kilometers, we had to rev it to redline in third ( approx it was 150+ kmph on speedo ) overtaking. We took it to chorwad sea shore and the car got struk, so once while the wheels were spinning free, the car reached the rev limiter in first gear, but it did not die down. Suddenly the rpm came lower as if rpm had hit the bump.

So IMHO, this is becasue of ultra agressive rev limiter. But also try this in some other car. If its the same behaviour as your car, then its rev limiter or else get the car checked.
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Old 25th November 2008, 22:51   #19
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This probably is one of the most hilarious threads in recent times
But no sweat Ym-ejn, we are here to help each other out,i'm sure we had similar questions regarding airbags opening up and engine cut off earlier.
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Old 26th November 2008, 00:01   #20
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Ok, let me clear up a few things here. Its not bad to revv the engine to its redline once in a while (well some of us do it all the while). Well, aren't the engines designed to take those revvs to begin with? That is why you have a redline and then a revvlimiter to avoid further damage.

A revvlimiter basically avoids the user from revving further. This could be to stop:
1. Overrevving of the engine, hence decreasing wear and tear of mechanical moving parts.
2. Also because fuelling and ignition maps are not optimum for such high revvs specially keeping in mind the fuel we get here.
3. Engine limitations, based on the Rod to Stroke ratio one can determine whether an engine is good for high revvs or not. Revvlimiter is mostly set according to this ratio and a few other parameters.

What does a revvlimiter do?

Basically, once the ECU senses that the optimum and maximum allowable revv range has been reached, it cuts off power to the engine either by:
1. Fuel cut off - Basically fuel supply is cut off to prevent further revving of the engine.
2. Ignition cut off - Basically the ignition timing is cut down.

Different cars have either of these methods of cutting down power, hence damage to the engine. For eg, in a baleno it is fuel cut off. In an elantra its ignition cut off.

Contrary to what most people think, revving an engine to redline is a lot less harmful than hitting the limiter. Specially in case of fuel cut off, what it does is completely cuts off fuel supply which can be detrimental to the engine. We all know that running lean is quite dangerous to an engine, running rich is a lot safer, now imagine an engine at 6500 rpm with no fuel supply at all. So always, try to shift just before the redline or bang on it. After some practice one will get used to shifting without hitting the limiter.
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Old 26th November 2008, 00:02   #21
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The Civic AT has a 5000RPM limiter at N and the normal 7000RPM (or so - have taken it there exactly once and I was looking at the road. I think it's set at 7200, but I'm not certain) while in D/S modes.

Almost every car with electronic injection has one. You simply cannot let an engine rev freely beyond a point - it will explode. I believe older fuel systems had their own way of controlling engine overspeed.

As for disc break noise, there is always some noise when taking it out of a cold start every day morning. It sounds like some sort of grinding sound that lorry's make when they come to a halt. This is more pronounced if the handbreak is kept applied overnight. The sound stops by the time I get to the main road from our lane (about... 15m of constant breaking because it's downhill). Going through the threads in the forum, I believe this is something that every Civic owner has to contend with - a "feature" so to speak, instead of a problem. I suspect it's the rust getting cleared off the rotors.
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Old 26th November 2008, 00:10   #22
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Quote:
Originally Posted by akshay1234 View Post
yes its there is most cars.
Akshay all modern day cars with MPFI systems have revvlimiters on them.

Quote:
Originally Posted by aseem View Post
Well I dont see it happening in my Swift.So I guess its a standard features in some cars.
Aseem, swift has a limiter too. In petrols its 6500 rpm IIRC. Like I mentioned before all cars with ECU have a limiter.

Quote:
Originally Posted by Ym-enjn View Post
Can sudden brake initiate Airbags? I did a test of that too.. It doesn't.
Airbags pop up only under a crash over a certain speed limit. Normally modern day ECU's are intelligent enough to make sure no airbags pop out if seat belts aren't worn. Also there are sensors below the passengers seat too in most cars. They sense weight on the seat and if there is nobody present it doesnt trigger that particular airbag on collision.

Quote:
Originally Posted by HotChillyPepper View Post
Add to all, Your ECU is logging in what you are doing with your engine. You will be caught in case you need to approch
ECU's self learn based on our driving. They cannot store data like the number of times you have hit the limiter etc. For that you need a data logger, which is quite expensive and useless in our daily drive cars. So don't worry about your dealer finding out this, he wont.

Quote:
Originally Posted by Ym-enjn View Post
Coming back to my ride, one good thing happened that the noise from brakes has disappeared after last night's heavy driving.
That could be due to some dust stuck in the brake pads. Normally the dust clears itself out on hard braking. Seems like that is exactly what happened in your case too.
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Old 26th November 2008, 08:24   #23
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Well, as others have said, everycar has one these days. If Alto has it, then Altis for sure have it.
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Old 26th November 2008, 13:41   #24
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Damn.. can this be increased.

No, just kidding.

Now that I know so much about this i dont think I will ever do that again, its my own car and from my own hard earned money. If anyone give me his car then I will try my hands with something like in this video on youtube:

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Old 26th November 2008, 16:28   #25
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lol..I dont know what to do laugh or cry???

do you guys read previous threads or do a search before posting this?

Rahul, has clearly explained it, I dont think more can be added.

Except the fact that video games are "games" real cars on real roads with real people are not!!!
Cheers
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Old 26th November 2008, 16:45   #26
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I have felt the same thing on the Altis as well. Unlike other cars which hit the limiter and jerk a little, the Altis feels as if the engine shuts for half a second.
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Old 26th November 2008, 17:07   #27
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Quote:
Originally Posted by iceman91 View Post
lol..I dont know what to do laugh or cry???

do you guys read previous threads or do a search before posting this?

Rahul, has clearly explained it, I dont think more can be added.

Except the fact that video games are "games" real cars on real roads with real people are not!!!
Cheers
Ya! I also think everything has been said here, lets close this thread. But who is Rahul and where has he explained clearly.
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Old 26th November 2008, 17:07   #28
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Originally Posted by live2drive View Post
Airbags deploy only in case of a crash and not on sudden braking..

they did on the first generation of cielo glx
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Old 26th November 2008, 17:16   #29
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Rahul is mclaren1885
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Old 26th November 2008, 17:41   #30
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Quote:
Originally Posted by yamracing View Post
I have felt the same thing on the Altis as well. Unlike other cars which hit the limiter and jerk a little, the Altis feels as if the engine shuts for half a second.
Its same for other cars that I have tried on. OHC and Alto.

Secondly, I do not feel that you should be worried about hitting the rev-limiter, that is precisely the reason it is there, it won't go beyond the point where it can be 'hard' on engine...
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