ZF4hp22

[guyh2]

I am looking into running a Mshift with a ZF4hp22 out of an old BMW.
It is actually being mated to a Land Rover 300tdi and being installed in a horsebox!

Obviously, due to the end application this needs to be reliable. I have been searching for info on the PWM control of the EPC solenoid which controls the line pressure. Frequency? duty? anything?

And its use, is this modulated by load to stop clutches slipping or is it varied to allow 'soft' shifting or both?

Has anyone 'scoped an OEM ECU?

Are there any 4hp22s up and running?

Cheers
Guy

[spurge]

Hi, i've just ordered a kit to work with a ZF4 HP24 which i'm fitting to my range rover classic behind a BMW 3.0d(td6) engine. I've spoken to someone that has the ZF technical data for these gearboxes and is going to dig it out, he got it for when he was involved with modifying compushift to work with the ZF box several years ago. I will let you know how i go on and if the information turns up.

[Mustang68]

For customer I have msshift a 4hp24 in a Freelander (only the looks, it has a tube frame) offroad rally car, the engine is controlled by a MS3pro. It has already some miles on it but it is now down because of some other 'problems'. They have also a older Rangerover rally car also ms3(x) but has a compushift controlling the 4hp24 this maybe the car they modified the compushift for. (They used a MOTEC to control the engine before the MS3(x) so the compushift is older).
I build the msshift like a 4L60E, Lance changed some code for the gear-selector inputs. We used the older rangerover reliably selector which pulls to ground (like a 4L60E), the newer unreliably expensive selector puts out 12v (the compushift uses this one).

I don't know if bmw are using the same parts.

But we are going to build a Landrover Defender with a MS3pro and Msshift for a daily drive.

Jacco

[guyh2]

Good news that there are others trying this

I have lots of technical info on the boxes, but the bits I am missing are the 'Holy Grail' ones, the OEM type ones i.e. the stuff ZF would have sent to BMW/Land Rover/Jaguar etc telling them how best to control the box. That would answer all the questions

I know these questions can be answered by experimentation, but I am not too keen on burning out clutch packs! Not enough time to keep stripping the box down.

I have found that the EPC solenoid is run at about 7-8Khz
Pressure-wise, in the non-electronic box, 100psi @ idle & 150psi is a 'ballpark pressure' for normal driving. The only test info for the 'electronic' box I could find was a 8.5 - 10.5v measured on the EPC line in 'D' at idle, wheels off the ground.

[spurge]

Hi, have now got my kit and going to start building, is there anything i need to do differently for the zf gearbox? Still haven't found the elusive pressure PWM info, have lots of vehicles in and out the workshop with these boxes, could try recording whats happening on these, whats the best thing to use? And would it help?

[guyh2]

Hi, have now got my kit and going to start building, is there anything i need to do differently for the zf gearbox? Still haven't found the elusive pressure PWM info, have lots of vehicles in and out the workshop with these boxes, could try recording whats happening on these, whats the best thing to use? And would it help?

Any info would certainly help. Confirm PWM frequency, PWM % vs load & rpm & during changes vs load & rpm - they would all be very useful
The other way would be to drive a similar (or your existing vehicle) through a set routine trying to explore all variations and then tune the Mshift setup to imitate that. Then you can tweak to your own driving style.
I don't have that luxury as I am installing a box in a completely different vehicle that, for starters, weighs double the original and mated to an engine that never had the electronic box - so lots of unknowns

As to the 'best thing' a multichannel digital storage scope / logic analyser would be best
Depending on how 'tech' you are, you could easily make a full datalogger with an Arduino (or similar) with an SD card and a bit of coding.

The real question is what do you have available to hook up?

[spurge]

Basically anything land rover, always got a p38 range rover or disco 2 auto in the yard somewhere, they would give relevant data for what we are trying to achieve. Will let you know how i go on, thanks for the reply.

[zen]

any updates?