Thread: Discovery 2 TD5 Torque Converter Mods

I had mine rebuilt. At the time it was a 3000rpm stall converter but had blown out to 3500rpm. It had cooked the friction material so I had it redone as heavy duty as possible while dialing it bak down. The guess is it should now lock up around 2200rpm.

I thought that the lock up was done via the computer on the DII it will come on at 74 kmh and only once the oil is at a certain temperture, but hey I could be wrong

80k's on mine.. and yes not until the temp is correct.

i think they mean the stall revs tho which is about 3000 - 3200 if you nail it or waaaayyy above that in sports mode...

remember its designed for the normal engine and i think its designed for peak torque / power and as its a small engine thats probably why its so high?

Thanks

Steve

Originally Posted by stevo

I thought that the lock up was done via the computer on the DII it will come on at 74 kmh and only once the oil is at a certain temperture, but hey I could be wrong

Your not wrong... The Lock Up is ECU controlled...

Stall speed is around 2250rpm IIRC (Rave not here at the moment)

And I think you'll find the 'torque converter' guy is more than happy to help this bloke lighten his wallet $600.00

It amuses me no end...

Yes, it may be worn or need overhaul, but otherwise, why would a large manufacturer fit a sub spec torque converter when it *could* be lower?

Originally Posted by Robbo

One area that I think my Disco could be improved in is the torque converter. I believe that the lock up RPM or stall Rpm is too high and that the motor tends to be revving more than it needs to be. I am wondering whether anyone else has replaced or has had there standard torque converter modified. I have been speaking to a torque converter specialist and he agrees with me and believes the lock up on the torque converter on a TD5 is about 1000 rpm more than it should be. My TD5 has been re flashed with nothing to crazy but as I said I believe it is the one weak link that I am thinking about altering. I am very interested in hearing other peoples experiences and opinions on this topic. With me doing all the installation and removal it would be about a $600 proposition.

Hi Robbo,

have a read here :

Ashcroft Transmissions

Dave

No I am not talking about the electronic lockup I am referring to the stall speed of the Torque converter which I believe to be too high. (around the 2800rpm). I think the TD5 would benefit from having a stall speed where most of its torque is at it peak and that is around the 2000-2200 rpm.

Why would a large manufacturer fit a sub spec torque converter when it *could* be lower?

Well too answer the question Tombie. Why have you had to do so many mods to your engine to get the best out of it??????????????
Transmissions are often something that don't have as much time spent on the design of the vehicle as the power plant.
I can not understand why the torque converters stall speed is above where the motor has its best torque. It just seems to me that the motor is being revved harder than it needs to be in order to gain speed.

In a nutshell...

The TD5 is a tiny motor... It wont hold 2000rpm under heavy loadings.
And when chipped, peak torque is a little higher....

Also, look at trans behavior as it maintains acceleration. Lowering the stall will reduce this ability.

Originally Posted by Tombie2

Yes, it may be worn or need overhaul, but otherwise, why would a large manufacturer fit a sub spec torque converter when it *could* be lower?

The why alter anything?

Why do ashcrofts fit a lower stall convertor?

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.