auto gearbox diy compushift..geeks only..

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zen

zen

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gonna be fitting p38 zf hp24eh box in my 2 door..anyone know whats required elecy front..do i need the p38 autobox ecu? (i hope not as it seems to talk to body ecu and engine and transferbox ecu..)
wondering if i can manually control box via the solenoids..if so how?
never had auto before..so a learning curve..(steep no dought)

whats the torque converter lock up solenoid for?

aiming to make..(dont pooh pooh,once i understand how box works the electronics will be simple enough)..a diy compushift...fancy sequential semi auto (manual clutchless) and full auto at a flick of a switch...
 
zen said:
gonna be fitting p38 zf hp24eh box in my 2 door..anyone know whats required elecy front..do i need the p38 autobox ecu? (i hope not as it seems to talk to body ecu and engine and transferbox ecu..)
wondering if i can manually control box via the solenoids..if so how?
never had auto before..so a learning curve..(steep no dought)

whats the torque converter lock up solenoid for?

aiming to make..(dont pooh pooh,once i understand how box works the electronics will be simple enough)..a diy compushift...fancy sequential semi auto (manual clutchless) and full auto at a flick of a switch...
Click to expand...

hmm interesting,lock up solenoid does what it says by locking clutch in t/c so its straight through drive ,box is basically the earlier box with solenoids instead of the govenor
 
If you have RAVE look in the gearbox section it tells you how it works and you probably need an ecu for the torque reduction to work the other solenoids should be able to be wired with a bit of inventive wiring to a gear lever to make it a manual automatic but I doubt if you will get it fully automatic without ecu and all sensors that control the changes.
 
If you use the ECU from the P38 ZF4HP22, I'm pretty sure it will work without the BECM or transfer box ECU with a bit of electrical jiggery pokery, but you will need all the sensor inputs.
 
I would think making it a semi-auto box similar to tiptronic or steptronic wouldn't be so difficult as all you would need to do is actuate the solenoids required for each gear shift....making a full auto would be quite a task as the box would need info from various sensors and engine torque values etc so it knows when to shift and to which gear etc...
 
Ashcrofts sell a unit that allows playing with all the settings.
Operating the solenoids manually and controlling oil pressure would be fraught with problems, miss sequence the shift, goodbye gearbox.
 
didn,t need a ecu , but you have to check the oil sensor the xyz switch and all those
switch in the box ,, the early ion and the old version is not the same but don,t known much about { mean the electric connector plug is not the same ) so you have to switch over for the 4hp222 to the 24

success
 
To have it working as a full automatic, then you need the g/box ecu, but it requires an engine speed signal from the engine ecu and if you loose this signal it defaults to 3rd gear. You also need a throttle angle signal from the engine ecu to get the kickdown to work properly. It would probably be easier to get the gearbox to work in a semi auto mode as this requires a common 12v feed for the solenoids and pressure regulator and these are activated by grounding the individual valves. However as implied above not sure what will happen if you select 1st gear at 90mph!
 
cheongthong said:
didn,t need a ecu , but you have to check the oil sensor the xyz switch and all those
switch in the box ,, the early ion and the old version is not the same but don,t known much about { mean the electric connector plug is not the same ) so you have to switch over for the 4hp222 to the 24

success
Click to expand...
Not so, the ZF4HP22e and ZF4HP24e have identical connectors on the P38.
 
so...are all the valves just 12v/gnd operated?..no need for pulse modulation then??
semi auto sequential is fine for now...cant afford ashcroft box at present..
i have all the sensors required though, ie speed tps etc, though they are feeding ms ecu for engine..
ms do a gearbox ecu, but that has no info on zf, and by all accounts wont be easy to do..
 
zen said:
so...are all the valves just 12v/gnd operated?..no need for pulse modulation then??
semi auto sequential is fine for now...cant afford ashcroft box at present..
i have all the sensors required though, ie speed tps etc, though they are feeding ms ecu for engine..
ms do a gearbox ecu, but that has no info on zf, and by all accounts wont be easy to do..
Click to expand...
Oil pressure solenoid is modulated, the other are sequential on/off, get the tining wrong and BOOM
I can give you some technical info on the boxes if you PM me with an email address.
Still think the easiest way would be a P38 ZF4HP22 ECU which would take care of oil pressure and sequencing and you can still use it as a manual.
 
Think this is a load of bollocks idea, not worth bothering with. As i see it you cannot run the box without the ECU it simple will not work. The ECU is interfaced with engine speed, load and road speed info to make changes electronically the two door simply does not have those interfaces. It is a none starter for me.
 
wammers said:
Think this is a load of bollocks idea, not worth bothering with. As i see it you cannot run the box without the ECU it simple will not work. The ECU is interfaced with engine speed, load and road speed info to make changes electronically the two door simply does not have those interfaces. It is a none starter for me.
Click to expand...
You could run the box with a Rasbery Pi if you were any good at programming, it's not that difficult.
 
ok..yep pwm at about 1knz for oil..will look into hp22 ecu.that sounds promising,save alot of work..

getting sequence wrong..well i wont...simple..

oh and wammers..i have all inputs on car ecu will need..ie speed,tps,injection load..etc..though i can see issue inthat lr ecu will not be compatable with megasquirt

though..once i can get my head around how it all works..which is what i am attempting to do, i can use the info to setup megashift ecu..this is so much cheaper than compshift, and better..ie allows maps,etc AND importatly will talk with engine ecu for all inputs required..


though all i am after at present is manual operation of gearbox..i can live without full auto...
pm sent
 
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what happens with solenoids when in..neutral.park or reverse..nothing in rave i can see to suggest state they in...
i assuming at present that reverse is mechanicaly selected, but what to set the forward gear solenoids to...same with neutral and park..

getting the converter solenoid to energise will need something to monitor forward speed, thats not too hard, and i guess oil solenoid can be crudely set with 2 settings to allow smooth or quick gearchanges...(via switch controlling pwm signal generator,)
this i am assuming is a constant signal and not just on gearchanges?
 
Interface to Petrol Engine Control Module (ECM)
(Z132)
The Auto Gear Box Control Unit (Z255) takes the
engine torque, engine speed and throttle angle
signals from the ECM, calculates which gear is
required, outputs to the solenoid valves and sends a
torque reduction signal back to the ECM, thereby
retarding the ignition point on each of the cylinders
and so giving a reduction in engine power during
gear changes that result in a smooth change.
The engine torque is received by the Auto Gear Box
Control Unit (Z255) on its pin 21, the engine speed
on pin 3 and the throttle angle on pin 47. The torque
reduction signal is sent to the ECM from the Auto
Gear Box Control Unit (Z255) via its pin 32.

from rave...

i would be hoping if these are analogue signals?? ie

not can bus as on seperate pins..would be nice if taking pulse from injector for torque.
direct tps voltage for throttle angle
engine speed 5v or whatever ignitor feed signal...
 
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