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Old 8th October 2009, 12:49   #1
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Question Engine braking with a Civic?

I test drove a Civic VMT this weekend (and booked an SMT yesterday) where I did a little engine braking - which I thoroughly enjoyed.

My question is: Is engine braking a safe/advisable habit for a Civic - what with it's iVTEC, disc brakes, ABS/EBD and other alphabet-soup technologies?

I currently regularly do this with my Palio - mostly just to enjoy the down-revving engine note more than preserving the brakes which give no sense of confidence at all anyway
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Old 8th October 2009, 13:22   #2
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It is safe, but it does tend to increase engine wear a bit.

But you're better off replacing piston rings than overheating your brakes on a hilly section and ending up having to replace your whole car.

Also make sure you revv match before shifting to a lower gear, this will not only make the downshift faster/smooth but will also increase clutch life.

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Old 8th October 2009, 13:30   #3
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What do you mean by "rev match" ? Does that mean I drop the revs to a low enough level (say 4k - 5k rpm?) so that the next downshift does not over-rev the engine?
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Old 8th October 2009, 13:38   #4
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Engine braking is safe as long as you do not cross the redline.Honda,toyota and mistubishi engines are free revving.The best thing you can learn is to mix and match it with normal braking.Initially avoid going from 5th to 3rd directly untill you learn what rpm it will go to if done that way.First try 5th to 4th and then brake then 4th to 3rd and then brake.Thereafter you can mix more jabs on the brakes along with the gear shifting.For ABS(in case of civic), keep your leg on the brakes rather than jabbing.Beleive me , engine braking will help you control the car in a way you could never imagine earlier.During slopes try using engine braking alone.But a look at RPM meter is a must atleast during the learning stages.After that you can rely on engine sound and vibration.
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Old 9th October 2009, 14:20   #5
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My style of driving heavily revolves around engine braking. Simply put, it offers me more control, especially when used alongwith the brake pedal.

Don't worry about engine life. The Civic's engine will outlast you in all probability. Just don't mechanically over-revv (downshift to too low a gear at too high a speed).
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Old 9th October 2009, 14:37   #6
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Engine braking is highly desirable. It is the best way of controlling your speed. Just make sure you do not downshift to the extent that you cross the redline. What is no desirable (unfortunately very common) is to run de-clutched/in neutral. You must be in proper gear at all times.
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Old 9th October 2009, 14:56   #7
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Quote:
What do you mean by "rev match" ? Does that mean I drop the revs to a low enough level (say 4k - 5k rpm?) so that the next downshift does not over-rev the engine?
Rev matching is done to ensure that the engine is spinning at an rpm required by the gear you are down shifting into.

Procedure is simple :
Press the clutch and as you shift to a lower gear press the acc till the tacho reaches the desired rpm for the lower gear. Once you reach there, shift into that gear and leave the clutch.

If done quickly and perfectly, you shouldn't feel any jerk when downshifting.

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Old 9th October 2009, 14:59   #8
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I use engine breaking habitually. My Qualis was sold at >150000km and was still running with original brake pads. Of course, the engine was in top condition, too.
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Old 9th October 2009, 15:00   #9
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@shan2nu: In most cases you can let the synchromesh do it for you. My style of changing gears is to pause for a second in neutral before moving on. As a result I am able to handle some baulky gearboxes without noticing a thing.
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Old 9th October 2009, 15:02   #10
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Quote:
Originally Posted by Shan2nu View Post
Rev matching is done to ensure that the engine is spinning at an rpm required by the gear you are down shifting into.

Procedure is simple :
Press the clutch and as you shift to a lower gear press the acc till the tacho reaches the desired rpm for the lower gear. Once you reach there, shift into that gear and leave the clutch.

If done quickly and perfectly, you shouldn't feel any jerk when downshifting.

Shan2nu
This will require heel and toe and that needs practice.

and

Engine braking "ok" for diesels as well?
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Old 9th October 2009, 15:04   #11
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Quote:
Originally Posted by sgiitk View Post
Just make sure you do not downshift to the extent that you cross the redline.
Most of the modern day cars have a rev limiter and hence one cannot cross the redline!
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Old 9th October 2009, 15:10   #12
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Like most guys have described above engine braking is a safe way to control your speed, especially while going down a slope. Just don't jump gears to start with and go sequentially down the gearbox (5->4->3 and so on) and match revs as described in the post above.
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Old 9th October 2009, 16:11   #13
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Quote:
Originally Posted by sgiitk View Post
What is no desirable (unfortunately very common) is to run de-clutched/in neutral. You must be in proper gear at all times.
Can u pls explain that.

Clutch is not engaged. Engine is running free. How does it become damaging ?
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Old 9th October 2009, 16:16   #14
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most of my braking is using gears only...
on my zen, i end up challenging myself if i can drive in the city without touching the brakes (unless some dimwit comes in the way) and controlling the speed only with gears.. ahh, but thats me and my whims..
usually, when i downshift, i give a slight tap on the throttle to have the speeds of the shafts matching for the lower gear. its a lot of fun to get it right.
for the honda, you wouldnt need rev matching. just letting the clutch slip correctly would give a nice feel of driving
but engine braking is most certainly recommended but the only problem would be that with a car equiped with such good brakes, you run a high risk of someone T-boning you from the rear... take care about that.
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Old 9th October 2009, 16:32   #15
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Quote:
Originally Posted by mclaren1885 View Post
Most of the modern day cars have a rev limiter and hence one cannot cross the redline!
I wish life was that simple. The rev limiter just cuts of ignition and injection above the limit. It will not stop you from down-shifting into the verboten zone.

Say your rev limit is 6000. The engine is at 5500. You mistakenly downshift and the lower gear has a 20% lower ratio. So at that wheel speed the momentum will force the engine to 5500+20% i.e. 6600 rpm. It is true the rev limiter would have cut in, with no ignition and no injection. However,it will take some time for the engine to come down to below 6000. Voila you have over-revved the engine.
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