A727 Shift points

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Pete
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A727 Shift points

Post by Pete »

One for the techies...

Is it possible to change the shift points on a 727 and still retain its automatic valve body?

I assume the shift points are triggered by internal line pressures acting on the servos?

I would like to retain the automatic characteristics of the gearbox but have the shift points much higher.

We would like to get the race car to shift automatically but at 6000+ rpm for each shift.

I am sure this is "Too hard to do" but it is worth an ask to understand how the box functions.....
Pete Wiseman; Cambridge.

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AllKiller
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Post by AllKiller »

Why s that Pete, one hand on the wheel and the other holding a bacon sarnie ?
:lol:

Wont it make it an absolute Bananarama! to drive in traffic ?? and your MPG will be even more cream crackered
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Blue
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Post by Blue »

Yep, you need to change the governer weights inside the tailshaft, can be done in situ. Everything works on fluid pressure and engine speed as sensed by the kickdown linkage and the governer weights.

http://www.aandatrans.com/Departments/C ... -Kits.aspx

Not sure how this affects part throttle shifts as I've never messed with the weights before, my guess is it will only change the full throttle shift point.
Last edited by Blue on Sun Oct 20, 13 2:48 pm, edited 1 time in total.
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Pete
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Post by Pete »

AllKiller wrote:Why s that Pete, one hand on the wheel and the other holding a bacon sarnie ?
:lol:

Wont it make it an absolute Bananarama! to drive in traffic ?? and your MPG will be even more cream crackered
Race car, chap ;)

Thanks Blue and also thanks to Dave Bishop for his call :thumbright: :thumbright:
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MilesnMiles
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Post by MilesnMiles »

Pete, see this article to go with Blue's
http://www.moparmusclemagazine.com/tech ... ewall.html

I extended my gear shift points by lengthening the kick down rod. Worked for me, but not to 6000rpm :)
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shovelheadrob
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Post by shovelheadrob »

Full manual valve body, solenoid operated shifter, rpm chip to activate the solenoid. Easy to change & won't shift early if you lift a bit.
You can't have too much power, only a lack of traction!
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AllKiller
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Post by AllKiller »

Pete wrote:
AllKiller wrote:Why s that Pete, one hand on the wheel and the other holding a bacon sarnie ?
:lol:

Wont it make it an absolute Bananarama! to drive in traffic ?? and your MPG will be even more cream crackered
Race car, chap ;)

:
Benefits ?
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Pete
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Post by Pete »

Roydon wants both hands on the wheel for the 1-2 shift and the 2-3 shift and as he is built like a Hobbit he cannot use the shifter lock-out lever for reverse when he is strapped in - he is worried about the consequences if he overshoots the staging beam....

I think he will re-engineer the Bananarama! set up in the closed season as per Robs suggestion but at present he does not have a long enough shifter cable an will have to get one made to measure...
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AllKiller
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Post by AllKiller »

Ah got you :thumbright:
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Pete
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Post by Pete »

Blue wrote: .....Not sure how this affects part throttle shifts as I've never messed with the weights before, my guess is it will only change the full throttle shift point.
Thanks Blue and Miles - reading the article now...

So with regard to your comment above; I am lead to believe that if you did this modification on a Transmision with a standard Valve body, and if you drove the car "sensibly" on the street then it would up-shift at relatively low RPM. However, if you drive it like you stole it (i.e. Kickdown mechanism fully engaged) it would default to physopath mode and upshift (depending on the governor used) in excess of 6000+ RPM????

sounds great (and possibly too good to be true??)

I ask as I would not want to modify a street car to ONLY up-shift at 6000+rpm on every shift in every gear.....
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Pete
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Post by Pete »

Any views on the merits of B&M Transpacks as opposed to Shift Kits?

Cheers.
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shovelheadrob
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Post by shovelheadrob »

You can't have too much power, only a lack of traction!
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Pete
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Post by Pete »

Cheers Rob; I have been reading that; I just wanted any personal feedback from anyone with practical experience?
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Les Szabo

Post by Les Szabo »

I have practical experience of.......watching the Tach going past 7000 on the launch!.....grab 2nd QUICK!!!, pulled on steering wheel, cars goes left some......think you may have seen the vid?.......not so good, but could've handled it ok after a few runs.

Better way around it from what your suggesting may be>

http://www.jegs.com/c/Shifters_Shifter- ... 5/10002/-1


Les
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Pete
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Post by Pete »

Welcome back, Les.

This application is for a Column shift car - I have gone Air shift on the AWB....
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