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Old 4th July 2007, 16:52   #106
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I had posted this query earlier in another thread any gyaan on this:

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Sorry for bumping up this oldy. but man what a discussion.

Ok now the reason for bumping this up. Say your in second gear and your braking. You come to a speed in which the second gear will not pull the car. So you down shift but your too fast for first and it doesnt slot in.

I'm guessing this is because the speed of the input shaft of the gearbox is lower since the rpm in second gear is not much whereas the output shaft to the wheels is spinning faster as the car's speed is higher for first gear.

Sometimes this can be a pain. Aren't the synchros supposed to help match the speeds so one doesnt have to double clutch?

Is there any other workaround to make this a smooth shift. Revv matching is kinda difficult in the case you are approaching a speed breaker. Also rev matching for the first gear very occasionally results in a jerk.

Do we have no other choice but double clutch?
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Old 4th July 2007, 22:29   #107
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Quote:
Ok now the reason for bumping this up. Say your in second gear and your braking. You come to a speed in which the second gear will not pull the car. So you down shift but your too fast for first and it doesnt slot in.

I'm guessing this is because the speed of the input shaft of the gearbox is lower since the rpm in second gear is not much whereas the output shaft to the wheels is spinning faster as the car's speed is higher for first gear.

Sometimes this can be a pain. Aren't the synchros supposed to help match the speeds so one doesnt have to double clutch?
If the 1st gear on your car is synchronised, it maynot have anything to do with the gear box. And if the revvs in 2nd are low enuf not to pull the car in that gear, i don't see why you should feel the vehicle speed is too fast for 1st gear.

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Is there any other workaround to make this a smooth shift. Revv matching is kinda difficult in the case you are approaching a speed breaker. Also rev matching for the first gear very occasionally results in a jerk.

Do we have no other choice but double clutch?
I don't think there is a way around this prob. You could try n slip the clutch when you downshift but thats only gonna create more clutch related probs in the long run.

I suggest you take some time out n learn revvmatching/ heel n toe braking. It just takes a lil getting used to, but once you get the hang of it you'd pref using it whenever possible.

Shan2nu
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Old 5th July 2007, 00:47   #108
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loads of stuff.. dont know how I missed this thread.. Well.. I match the engine RPMs and shift gears. So if the situation demands..its 2nd from 4th.. and I always preferred a car with a tacho.. sad the Sparky has no tacho :(

Thanks a lot
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Old 5th July 2007, 13:23   #109
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Originally Posted by Shan2nu View Post
I suggest you take some time out n learn revvmatching/ heel n toe braking. It just takes a lil getting used to, but once you get the hang of it you'd pref using it whenever possible.

Shan2nu
Revvmatching is not a problem but in my case what happens is that the GC of the car is very low(lancer SFXi), Second gear will stall before the bump so I need to brake before the bump to a slower speed and 1st gear and then accelerate over the bump.

The down shift to a lower gear is easy but she doesn't slot into 1st unless the car is almost stationary. A little bit more speed and she refuses to slot in 1st from second.

Heel n toe I can't do as my legs are too long they touch the steering column and the I cant turn the foot horizontal as a result.
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Old 5th July 2007, 15:56   #110
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Quote:
Revvmatching is not a problem but in my case what happens is that the GC of the car is very low(lancer SFXi), Second gear will stall before the bump so I need to brake before the bump to a slower speed and 1st gear and then accelerate over the bump.
In that case, the only option you have is to come to a complete halt before the speed bump, slot into 1st and then accelelrate.

Quote:
The down shift to a lower gear is easy but she doesn't slot into 1st unless the car is almost stationary. A little bit more speed and she refuses to slot in 1st from second.
I've heard that some of the older synchromesh gearboxes didn't have synchronizers for the 1st gear. Not sure how the Lancer gearbox has been designed.

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Heel n toe I can't do as my legs are too long they touch the steering column and the I cant turn the foot horizontal as a result.
I have the same prob on the OHC Vtec but with practice, i've found ways to overcome this prob. Another contibuting factor to heel n toe technique is the pedal design/placement.

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Old 5th July 2007, 17:13   #111
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Quote:
Originally Posted by vid6639 View Post
The down shift to a lower gear is easy but she doesn't slot into 1st unless the car is almost stationary. A little bit more speed and she refuses to slot in 1st from second.
Vid - I don't know about the Lancer but on my car I sometimes shift into 1st with the car moving & it happens without any issues. What I do here is not try & snap it into gear but rather gently coax it & it works like a charm. Try & see if it works.

Also I should mention that I started doing this 1st gear shift right from the early days of my car so that could be why she shifts easily.
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Old 5th July 2007, 19:39   #112
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Vid, you should be able to put your Lancer into first gear when it's moving. I have done it on my friend's Lancer.
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Old 6th July 2007, 11:18   #113
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Default Clucthing on neutral

I am new to driving so this question.
When I see a speed breaker I shift to neutral and wait till the car slows down or apply breaks and then shift to 2 grear (assuming I was on 4th). Is this the correct way or should I break to slow down then shift to 2nd gear. Which is better and which gives a better FE.
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Old 7th July 2007, 05:07   #114
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the right way would be brake whilein fourth then if necessary shift into 3 continue braking then into 2
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Old 7th July 2007, 11:33   #115
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Quote:
Originally Posted by sastradhar View Post
I am new to driving so this question.
When I see a speed breaker I shift to neutral and wait till the car slows down or apply breaks and then shift to 2 grear (assuming I was on 4th). Is this the correct way or should I break to slow down then shift to 2nd gear. Which is better and which gives a better FE.
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Originally Posted by paras211 View Post
the right way would be brake whilein fourth then if necessary shift into 3 continue braking then into 2
Guys,

Theres an entire thread discussing that.... check it out, and do continue the discussion there >

http://www.team-bhp.com/forum/techni...tml#post226145

cya
R
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Old 8th December 2010, 16:26   #116
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Default Heel-Toe

Resurrecting an old thread as,

I am yet to get hang of heel-toe while braking and going down a gear or two.

Is this Car* dependent? On type of fuel the Car runs?

I know the advantages of blipping and I can't go down a gear on my Motorcycle w/o blipping, but in a Car...
(While starting the Motorcycle in cold early mornings, the gear just doesn't go home (up) and a blip and it smooth-ens out).

*on the placement of pedals?

Edit--searched for videos, but found Senna's videos everywhere. Can some bhpian help A video illustration will be nice.

Last edited by Sheel : 8th December 2010 at 16:29.
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