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We are very pleased to announce the arrival of the "Compushift" for the ZF 4HP22/24 EH

Brief Description of operation

The Compushift is a "stand alone" ECU that controls the electronic version of the 4HP22/24. It takes 4 inputs from the vehicle and calculates the shift points, shift pressures and converter lock up speed depending on the shift tables or "maps" in the ECU. This is a major step forward for those using the ZF in different applications as you are able to map your own shift speeds and pressures very easily and quickly without the complexity or hassle of a laptop.

Inputs

The ECU needs to be wired to accept a minimum of 4 inputs as mentioned above, these are :

1) "XY switch" on the selector shaft to the left of the electronic ZF is a position switch, the loom of the Compushift needs to be wired into this switch so the ECU knows what gear you have selected with the shifter. You also wire the reverse lights through this switch (no relay needed) and the starter inhibit through the low current starter solenoid signal wire. All wires are colour coded in the fitting instructions to make this easy.

2) Clean 12V ignition switched feed.

3) Throttle Position Sensor (TPS). The ECU needs to know the throttle position, this signal takes the form of a 0 > 5 V signal which can come from either the existing vehicle TPS if you are converting a TD5 or 2.4 TDCi or you can use a small linkage connected to the throttle mechanism and use this to activate a separate small TPS. On startup this needs to be calibrated but it"s very easy, you just press the relevant button on the ECU or display and you have 5 seconds to fully stroke the throttle to max and back to zero, the signal "self calibrates".

4) Temperature Sensor, this is used for 2 reasons, the shift pressures are adjusted depending on the oil temp to allow for the changing viscosity and if the system is used with the optional display you can monitor this temp and check for overheating. The Sensor will need to be brazed into the autobox sump below the oil level line.

Display

Included in the kit price is a display unit which plugs into the ECU and allows you to utilise more functions of the ECU as well as making the "Mapping" setup much easier and allows you to watch what the transmission is doing as you are driving, ie what gear you are in, oil temp, converter lockup, vehicle speed, Etc. Click for Photo of Display

Driving modes

You are able to choose from 4 types of driving modes :

1) "Automatic", Just like a stock auto,

2) "Automatic with Switch shift", if you fit a rocker switch into a plug on the loom and select this mode you can do one of two things depending what value you input into the setup option called "SW shift %". Note down shift from 4 to 3 and 2 will give engine braking but "D" 1st is a free wheel on overrun so will not give engine braking.

a) If set to say 5% the vehicle will drive as an "auto" but when you press the rocker switch it will change gear and you will have manual control until you drop the throttle below 5% at which point it will revert back to being in "auto". You can also shift up with the switch at a standstill and it will pull off in 2nd.

b) If this value is set to 0% it will drive as an "auto" but when you press the rocker switch to change gear it will now stay in manual mode irrespective of throttle position. Moving the shifter from D to 3 and back will return to normal auto mode. The ECU will look at the shift tables and the max engine RPM and block shifts outside these parameters.

3) "Automatic with Tow mode", you will need to fit a switch between the neutral and the up-shift wire and when this mode is selected the vehicle will drive as an auto but when you press the switch both the shift speed and pressures will be changed to the values you have pre-set, described below. Note the converter will stay locked until you shift down to 3rd, this gives improved downhill engine braking but if you use this mode you will need to adjust the shift tables accordingly so you don’t pull the revs down too low before the converter unlocks.

4) "Manual" This mode must be used with extreme caution!! Position 1 on the shifter is just 1st, Pos 2 in just 2nd, Pos 3 is just 3rd, Pos D is just 4th. It does not look at the shift tables to inhibit unwise shifts, if you put it in 1st at 70 either the engine or the box or both will fail !

Setting up

As mentioned above you are able to choose from 3 preset maps depending on the engine type and then you can just leave it at that or you can scroll through the menus using the display unit and adjust a number of other factors such as:

"Pressure Adjust", this will raise or lower the shift pressures on the chosen map, this can be adjusted either using the display or if you don"t have the display you can adjust this with a screw on the ECU.

"Shift Speed Adjust", this will raise or lower the shift speeds on the chosen map, this can be adjusted either using the display or if you don"t have the display you can adjust this with a screw on the ECU.

"TCC Enable Speed", once the transfer case ratio, diff ratio and tyre size are inputted you can input the speed at which you would like the converter to lock up.

"TCC Max Throttle", this allows you to adjust the percentage throttle position that you would like the converter to drop out of lock up,

"Downshift Offset" this value adjusts the kickdown sensitivity, the higher the value the more readily it will kickdown.

"Max upshift RPM", to prevent over revving, the ECU knows the engine speed from the preset ratios and the autobox speed sensor.

Applications

We have helped develop the Compushift for the conversion of the 2007 2.4 TDCi Defender to Automatic but it can be used anywhere the ZF 4HP22/24 EH is used, ie.

Defender TD5 conversions, 2.8 TGV auto conversions, V8 competition vehicles.

This system is perfect for the conversion world as you can adjust all the variables to suit your application to get the vehicle driving as you want it to drive.

Compushift	£750
We are very pleased to announce the arrival of the "Compushift" for the ZF 4HP22/24 EH Brief Description of operation The Compushift is a "stand alone" ECU that controls the electronic version of the 4HP22/24. It takes 4 inputs from the vehicle and calculates the shift points, shift pressures and converter lock up speed depending on the shift tables or "maps" in the ECU. This is a major step forward for those using the ZF in different applications as you are able to map your own shift speeds and pressures very easily and quickly without the complexity or hassle of a laptop. Inputs The ECU needs to be wired to accept a minimum of 4 inputs as mentioned above, these are : 1) "XY switch" on the selector shaft to the left of the electronic ZF is a position switch, the loom of the Compushift needs to be wired into this switch so the ECU knows what gear you have selected with the shifter. You also wire the reverse lights through this switch (no relay needed) and the starter inhibit through the low current starter solenoid signal wire. All wires are colour coded in the fitting instructions to make this easy. 2) Clean 12V ignition switched feed. 3) Throttle Position Sensor (TPS). The ECU needs to know the throttle position, this signal takes the form of a 0 > 5 V signal which can come from either the existing vehicle TPS if you are converting a TD5 or 2.4 TDCi or you can use a small linkage connected to the throttle mechanism and use this to activate a separate small TPS. On startup this needs to be calibrated but it"s very easy, you just press the relevant button on the ECU or display and you have 5 seconds to fully stroke the throttle to max and back to zero, the signal "self calibrates". 4) Temperature Sensor, this is used for 2 reasons, the shift pressures are adjusted depending on the oil temp to allow for the changing viscosity and if the system is used with the optional display you can monitor this temp and check for overheating. The Sensor will need to be brazed into the autobox sump below the oil level line. Display Included in the kit price is a display unit which plugs into the ECU and allows you to utilise more functions of the ECU as well as making the "Mapping" setup much easier and allows you to watch what the transmission is doing as you are driving, ie what gear you are in, oil temp, converter lockup, vehicle speed, Etc. Driving modes You are able to choose from 4 types of driving modes : 1) "Automatic", Just like a stock auto, 2) "Automatic with Switch shift", if you fit a rocker switch into a plug on the loom and select this mode you can do one of two things depending what value you input into the setup option called "SW shift %". Note down shift from 4 to 3 and 2 will give engine braking but "D" 1st is a free wheel on overrun so will not give engine braking. a) If set to say 5% the vehicle will drive as an "auto" but when you press the rocker switch it will change gear and you will have manual control until you drop the throttle below 5% at which point it will revert back to being in "auto". You can also shift up with the switch at a standstill and it will pull off in 2nd. b) If this value is set to 0% it will drive as an "auto" but when you press the rocker switch to change gear it will now stay in manual mode irrespective of throttle position. Moving the shifter from D to 3 and back will return to normal auto mode. The ECU will look at the shift tables and the max engine RPM and block shifts outside these parameters. 3) "Automatic with Tow mode", you will need to fit a switch between the neutral and the up-shift wire and when this mode is selected the vehicle will drive as an auto but when you press the switch both the shift speed and pressures will be changed to the values you have pre-set, described below. Note the converter will stay locked until you shift down to 3rd, this gives improved downhill engine braking but if you use this mode you will need to adjust the shift tables accordingly so you don’t pull the revs down too low before the converter unlocks. 4) "Manual" This mode must be used with extreme caution!! Position 1 on the shifter is just 1st, Pos 2 in just 2nd, Pos 3 is just 3rd, Pos D is just 4th. It does not look at the shift tables to inhibit unwise shifts, if you put it in 1st at 70 either the engine or the box or both will fail ! Setting up As mentioned above you are able to choose from 3 preset maps depending on the engine type and then you can just leave it at that or you can scroll through the menus using the display unit and adjust a number of other factors such as: "Pressure Adjust", this will raise or lower the shift pressures on the chosen map, this can be adjusted either using the display or if you don"t have the display you can adjust this with a screw on the ECU. "Shift Speed Adjust", this will raise or lower the shift speeds on the chosen map, this can be adjusted either using the display or if you don"t have the display you can adjust this with a screw on the ECU. "TCC Enable Speed", once the transfer case ratio, diff ratio and tyre size are inputted you can input the speed at which you would like the converter to lock up. "TCC Max Throttle", this allows you to adjust the percentage throttle position that you would like the converter to drop out of lock up, "Downshift Offset" this value adjusts the kickdown sensitivity, the higher the value the more readily it will kickdown. "Max upshift RPM", to prevent over revving, the ECU knows the engine speed from the preset ratios and the autobox speed sensor. Applications We have helped develop the Compushift for the conversion of the 2007 2.4 TDCi Defender to Automatic but it can be used anywhere the ZF 4HP22/24 EH is used, ie. Defender TD5 conversions, 2.8 TGV auto conversions, V8 competition vehicles. This system is perfect for the conversion world as you can adjust all the variables to suit your application to get the vehicle driving as you want it to drive.