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Auto gearbox 3 - 4 - 5 gear lag

Posted: Sat Jan 19, 2013 8:13 am
by Zoro2006
Seems that users with Auto gearbox has lag going with 3 or 4 or even 5 gear. Doug maybe you have ideas why this happens ? 1st and 2nd gears don't have these problems.

Re: Auto gearbox 3 - 4 - 5 gear lag

Posted: Sun Jan 20, 2013 11:21 pm
by sass
My friends has same problem.

avtomat gear
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tiptronic gear
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Re: Auto gearbox 3 - 4 - 5 gear lag

Posted: Mon Jan 21, 2013 12:29 am
by Zoro2006
maybe it's due torque convertor which Auto gearboxes have ?

Re: Auto gearbox 3 - 4 - 5 gear lag

Posted: Wed Feb 20, 2013 5:22 am
by Mounty
From what the boys and girls at flashrpotuning.com have confirmed, and you should have noticed this yourself, is that it happens at vtec crossover. When the vtec mechanism turns on, needing oil pressure to move that "pin" inside the Rockerarms, there is a slight lobe. They said it would not be a problem to have that 'ironed' out. I will have to buy an e-tune from them, but at the moment, I am not finished installing parts, so I will have to wait, to get the complete tune job.
This happens to me too in 3rd and 4th, also in ss mode, but not as noticeable.
Mounty

Check out my vid on youtube... on the dyno... vtec lobe is audible... http://www.youtube.com/watch?v=SEouSBMSKP8

Re: Auto gearbox 3 - 4 - 5 gear lag

Posted: Fri Mar 01, 2013 12:59 am
by Zoro2006
Mounty wrote:From what the boys and girls at flashrpotuning.com have confirmed, and you should have noticed this yourself, is that it happens at vtec crossover. When the vtec mechanism turns on, needing oil pressure to move that "pin" inside the Rockerarms, there is a slight lobe. They said it would not be a problem to have that 'ironed' out. I will have to buy an e-tune from them, but at the moment, I am not finished installing parts, so I will have to wait, to get the complete tune job.
This happens to me too in 3rd and 4th, also in ss mode, but not as noticeable.
Mounty

Check out my vid on youtube... on the dyno... vtec lobe is audible... http://www.youtube.com/watch?v=SEouSBMSKP8
this is not due VTEC crossover, this is two different things.

Re: Auto gearbox 3 - 4 - 5 gear lag

Posted: Sun Mar 31, 2013 4:46 pm
by mabo
Read bout converter lock\unlock, this dip is caused by this function of AT tranny, usually looks like one more small gear has changed. Often see this under part throttle acceleration when rpms r almost still but speed continue rising. 1-2 gears have big torque multiplication and this function ( converter lock ) not working under full throttle to reduce stress on tranny, but i can cofirm that 2nd gear can behave like this under light throttle accel.
This function was implemented to save on losses in converter duruing cruising. I can be wrong but gear ratios r fixed and nothing else on a way from crank to wheels can cause this rpms dip.