Discovery 2 TD5 Torque Converter Mods

Torque Converter Upgrades
The ZF auto as used in the LandRover vehicles uses three different diameters of torque converter. Small. Medium and Large.Photo here
"Small" is used on the 300 Tdi, P38 diesel and the TD5 "Medium" is used on the 3.9, 4.0 and the later 4.6 P38 "Large" is used on the early 4.6 P38"s
The converter has a lock up clutch inside and the smaller one struggles to cope with a stock engine, never mind a tuned one.
When the "stage 2" ZF is being used with a V8 or 2.8 TGV you have the option of using the larger diameter 4.6 torque converter at no additional cost but on a V8 you will also need the 4.6 boss and flexplate assy to match the bigger converter. When using on the 2.8 be sure to order the conversion kit to fit the bigger 4.6 converter. This bigger converter is recommended on the big V8"s and the 2.8 as it keeps the revs and heat down.
If you have a tuned TD5 engine, in addition to the stage 1 or 2 options mentioned above we are now able to replace the "Small" diameter torque converter for the "Medium" diameter one. This gives you the benefit of the larger lock up clutch and the lower stall speed V8 torque converter which will take up drive earlier. This option is an additional £ 250.

read this like dave said, usefull info.
Ashcroft Transmissions

cheers phil

OK My apologies...

I'll eat some humble pie on this one :cool:

he he:D
dose it tase as good as they say??:p

stall speeds are also dependant on the power and torque of the motor in question.
i played around with a few in a powerglide on a 308 torry. outta the box the convertor was 3800rpm lock, on the track it was closer to 4200 lock.

cheers phil

if the same torque converter is used for both the diesel and the V8s then there is a good chance that a compromise has been achieved.

When I lived in the UK most of the vehicles were manuals. It has been a few years now so things could have changed but I suspect that the majority of the autos are used with the v8s and the manuals with the diesels. So I strongly suspect that if a compromise has been arrieved at on the TC it would be in favour of the V8. So perhaps there is scope for modifications of the TC when used behind a diesel (as long as the power is there to cope with the lower stall speed)

Quote:

---

Originally Posted by discowhite

he he:D
dose it tase as good as they say??:p

stall speeds are also dependant on the power and torque of the motor in question.
i played around with a few in a powerglide on a 308 torry. outta the box the convertor was 3800rpm lock, on the track it was closer to 4200 lock.

cheers phil

---

Ditto

Quote:

---

Originally Posted by Tombie2

Whoa!!! Where does it say lower? They fit a LARGER diameter unit....

Stall / Lockup is still ECU controlled and goes by the ECUs requests...

---

Lockup can be controlled but stall speed is mechanical;)

urmmm lockup is mechanical under either hydraulic pressure controls or ECU and stall is hydrulic... (just to nit pic...)

what I think would be better suited to the discos is the medium stall speed converter (which is a nice compromise) with manual control on the lockup.

Umble Pie:

Quote:

---

Originally Posted by discowhite

he he:D
does it taste as good as they say??:p

---

I saw it on "The Worst Jobs in History" and it "Umble Pie" - (note Umble not Humble) sounded gross - it's made from offal.

Quote:

---

Originally Posted by Blknight.aus

urmmm lockup is mechanical under either hydraulic pressure controls or ECU and stall is hydrulic... (just to nit pic...)

what I think would be better suited to the discos is the medium stall speed converter (which is a nice compromise) with manual control on the lockup.

---

Correct, but I was talking control, as in stall speed is governed mechanically;) as in stall is by no means governed by the ECU:D

More HP = More flare in stall speed:D

yeah thats why I was nit picking....

did you know you can actually get a torque converter with an adjustable stall speed......

you probabley dont want to know about the cost of one.....

its not what its supposed to do but its a bug in the design.

it works by removing the restriction on the oil flow out of the TC thus more or less elimnating the restriction of the movement of the oil in the TC. By slowly applying the restriction you slowly decrease the flow rate of the oil through the TC which inturn increases the flow of oil around the internals of the TC (which is what provides the driving force) The idea behind it is so that you can leave an engine going flat out while its driving something (like a pump) that requires a preset RPM and lower the % of the power output of the engine to the driveline for creeping.

not the most elegant of explinations but for those who are familiar enough to understand the concept its near enough.