ECU Remap

BeenThroughItAll

Gloomendoom wrote: »

Didn't I just say that?

Well, that wasn't how I read it. I read 'in Low range I have loads of torque' and inferred a torque value-gearing correlation being suggested.


Whereas, as we clearly both understand, you have the same amount of torque in Low/High range and the way in which it is delivered in terms of performance changes.

Gloomendoom

BeenThroughItAll wrote: »

Well, that wasn't how I read it. I read 'in Low range I have loads of torque' and inferred a torque value-gearing correlation being suggested.

Ignoring frictional losses, clutch slip and torque converters, there is a direct and linear torque value-gearing correlation. The lower the gear the higher the torque.

It may be at the wheels, but that is where it is needed.

Nodding_Donkey

Gloomendoom wrote: »

I'm not convinced by this. In low 1st, my old Land Rover has torque by the bucketful.

I can't see it winning many races though.

Look at it this way, two Land Rovers with identical gearing, one produces more torque than the other so can go up the hill in 2 low whereas the first needs 1 low. Who gets to the top first?

Gloomendoom

Nodding_Donkey wrote: »

Look at it this way, two Land Rovers with identical gearing, one produces more torque than the other so can go up the hill in 2 low whereas the first needs 1 low. Who gets to the top first?

The one that has an engine that can rev more?

Slowly_does_it..

The question is not to get to the top first, the question is which landrover will get to the top more often and easiest without boiling, and both are towing a large trailer.

Would the auto box not be expecting the torque to be there, so would drop a gear and use the higher revs lower down in the box, therefore negating any increase in torque? Would an increase in torque remove some higher rev HP therefore confusing the box when it tries to use the higher revs?

I think it is a very valid question, watching for updates!
(personally I prefer petrol for towing, but I am different)

Gloomendoom

At the very least, the box will take into account the road speed, engine rpm and throttle position (load) and attempt to select the correct gear. If you mess with the output of the engine, you do risk confusing the gearbox. However, if the torque curve remains the same shape, the original settings should work... as I understand it anyway. It is possible (and quite easy) to remap the gearbox ECU to complement the remapped engine characteristics. I haven't found this to be necessary.

One thing I was advised to do when towing a heavy load with this particular gearbox was to lock the box out of top to prevent premature wear. This was from an Australian chap who had retired early on the proceeds of repairing knackered autoboxes.