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Transmission Relay Shift System

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Old 10-23-2007, 03:54 PM
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jaybuni
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Default Transmission Relay Shift System

Hi Everyone,

I apologise in advance if this topic has cropped up before but I did search the archives and couldn't get the answers to my simple questions.

My basic question is what is this and how will this little gadget improve the power delivery of the S4? The product description of the outcome once installed seems promising however need to ask those that have fitted this how good or bad is it?

Also Jager states that it is compatible with stock and their after market gear shifters. I have an aftermarket auto shifter from 928stuff with no acutator button. I simply press down to go past the locked gears etc. Will this be compatible with my gear shifter?

Here's the product from Jager:

http://jageng.com/garage9/product_in...28d7822abc537c

Any comments appreciated.

Thanks in advance

Cheers

Sy.
Old 10-23-2007, 04:17 PM
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Slantnose!
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Hey there.
It basically by-passes the switch under the accelerator pedal and makes it easier to drop down a gear.
Old 10-23-2007, 04:45 PM
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Alan
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Its just a kick down bypass possibly with a relay controlled by the shifter. You can do the same thing other ways.

They allude to the feature on the 94 & 95 Auto's they is called Dynamic Kickdown - this is not what they are offering - that is a much more complex control system. This is probably nice to have on the shifter though... to determine if you like it you could add a switch that does the same thing elsewhere and try it out. You can use it temporarily - but I know some folks drive around with it like this all the time.

Alan
Old 10-23-2007, 05:03 PM
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Charley B
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The activity that the bypass "improves' upon, is the very thing that makes the automatic so much fun to drive.
Old 10-23-2007, 05:14 PM
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jaybuni
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I'm soooo sorry, but I'm lost, confused and don't understand.

Please can someone explain in a bit more.

Cheers.
Old 10-23-2007, 05:16 PM
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Imo000
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Originally Posted by Charley B
The activity that the bypass "improves' upon, is the very thing that makes the automatic so much fun to drive.
The sluggish feel off the line?
Old 10-23-2007, 05:49 PM
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Charley B
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Originally Posted by Imo
The sluggish feel off the line?
Ok, that is funny, but I'm still going to ignore it.
Old 10-23-2007, 06:15 PM
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Alan
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OK look under your gas pedal - there is a switch - when you floor the throttle the switch remaps the shift points on the transmission - at WOT it gives you an earlier downshift and later upshifts - this gets you more performance at the expense of economy. This switch goes in parallel with that switch - so you can fool the car into thinking you are at WOT when you aren't ... you still get delayed up-shifting, 1st gear starts even with gentle throttle openings. you of course can be selective when you use it ... it changes the character of the car - like a "(more) sport mode" I suppose.

Alan
Old 10-23-2007, 06:28 PM
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jaybuni
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Thanks Alan

Having an aftermarket shifter, will this thingy majig work with my one? I don't have an actuator button.

Cheers
Old 10-23-2007, 06:48 PM
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BrianG
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It is hard to say, from that picture, what the kit's actuator mechanism is, and even more difficult to guess what your aftermarket shifter does.

If you can determine that the "push down" function of your shifter reproduces the un-locking action of the OEM "button", it should work.
Old 10-23-2007, 08:38 PM
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Bertrand Daoust
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Here is a link on how to by-pass the switch under the gas pedal:
http://members.rennlist.com/v1uhoh/kickdown.htm

Did't try it but looks quite easy to do.
Old 10-23-2007, 09:25 PM
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Nicole
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Hi Syed:

This system engages the kick-down relay when you press the button on your shifter. However, it is not connected to the shifter itself, but to the shifter mechanism further down in the console - hidden from view. Therefore it does not matter what shifter is installed in your car - it has no influence on the function of this kit.

So how does this work in real life driving situations?

Let's say you are putting along a hiway and want to pass a car in front of you. You could push the pedal all the way and engage the kick-down switch to force the transmission to shift back. Then the car would leap forward full force.

But you don't always need that full acceleration, along with the added fuel consumption at WOT. With the kit you just press your shifter button, the kick-down switch enables, and if your transmission thinks it's safe for the engine to run in a lower gear, it will downshift.

Similarly, you may want to downshift before you accelerate, so you are already in the right gear when you need the full acceleration. With the kit installed, you could trigger a such downshift easily by pushing the button on your shifter.

From what I understand the Mercedes transmission in our cars will not downshift, if it would over-rev the engine - but that's a transmission fuction, not a function of this kit.

The advantages of using this kit are:
1. You can downshift without engaging WOT
2. You won't jerk your passengers around with WOT downshifts when you only need a bit more acceleration
3. You'll save fuel by avoiding unnecessary WOT
4. You can trigger early downshifts, before you need the full acceleration
5. You can use any shifter you like, as long as it fits the 928 otherwise
6. The kit is totally invisible when installed.
7. No extra buttons, or switches from the electronic store...
8. Ergonomic operation with controls that already exist in the car
9. It costs a fraction of money and installation time as retrofitting the dynamic kick-down that Porsche offered in the 94 and 95 models
10. Comes with detailed installation instructions, pre-wired. Only requires drilling one small hole into the shifter mechanism - not visible from outside

Let me know, if you have more questions!

http://www.marketworks.com/storefron...975&i=26458466

Last edited by Nicole; 10-24-2007 at 06:40 PM.
Old 10-23-2007, 09:30 PM
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Charley B
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Nicole, is there anything the bypass does that you can't do by simply selecting a lower gear?
Old 10-23-2007, 09:33 PM
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If you select a lower gear manually, it won't upshift again until you move the lever forward.
Old 10-23-2007, 09:51 PM
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Charley B
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OK, I'll amend my question. Is there anything the bypass does that you can't do by simply selecting a different gear.


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