How to get 400Nm from RRC

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Originally Posted by uninformed

if we are talking road speed and LR aero dynamics then we need more torque and lots of it.

Axles shafts are easy to upgrade for reasonable dollars

IMO the R380 is only so good, even in stock rovers doing real work.

What is wrong with the 3.2 off road. Id have it over the 2.4/2.2 every day of the week. I would also have it over a 2.5 tdi making the same power.

That is not rocket surgery I can tell you that much ;)

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Yes, shafts are easy to upgrade, but even tough ,they break from time to time, specially if you fit tyres above 35" - I´ve expericenced myself rear ring and pinion failures and also an ARB failure.

I really dont know about the 3.2. This is one more time when all looks excellent on paper, but still dont know about real life. Id also have it over the 2.4 and the 2.2. In fact, in theory, I would have it over any other LR engine, but can only have a true honest opinion, if I drive one for a week or so and test it.

Regards

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Originally Posted by uninformed

I certainly would not call it very much either. Even when not comparing it to the stock diesel cars/4x4 we see on our roads and then taking into account the HP those race engines are making from their respective capacities

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For the use and performance figures its not much, for me!...was just a point of view, since someone claimed there was never a "wisp" emitted!

Regards

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Originally Posted by rovercare

“In theory, theory and practice are the same. In practice, they are not.”

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If theory and practice is not the same then either:

a. The practicians do not understand the theory.

or

b. The theory has been (over) simplified so is no longer a sufficiently accurate representation of the system.

Some things are so complex that they should be tested, such as comparing CFD and confirming flow or in the wind tunnel. A blanket hp rating on a motor based on A/F ratios and boost is an oversimplification that does not account for the associated technology and environments.

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Originally Posted by Slunnie

Some things are so complex that they should be tested, such as comparing CFD and confirming flow or in the wind tunnel. A blanket hp rating on a motor based on A/F ratios and boost is an oversimplification that does not account for the associated technology and environments.

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Of course theory should be validated! That is a completely different issue.

(most) CFD is not theory. Most CFD methods are numerical approximations of the theory, for situations where the theoretical equations cannot be solved analytically (completely) - often with many simplifications included. CFD also needs to be validated.

HOWEVER, a correctly implemented DNS (direct numerical simulation) is more accurate than any experiment.

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Originally Posted by Slunnie

Some things are so complex that they should be tested, such as comparing CFD and confirming flow or in the wind tunnel. A blanket hp rating on a motor based on A/F ratios and boost is an oversimplification that does not account for the associated technology and environments.

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There is no blanket HP rating, no such thing was even hinted at.
You need to read that entire post again and then get back to us.

This isn't some wild arse untested theory on how engines work. This is how a/f ratios, torque, egt and smoke interact.

Increasing power and torque substantially comes next. But only once you get the first relationships as it requires understanding of those to build upon.

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Originally Posted by isuzurover

Of course theory should be validated! That is a completely different issue.

(most) CFD is not theory. Most CFD methods are numerical approximations of the theory, for situations where the theoretical equations cannot be solved analytically (completely) - often with many simplifications included. CFD also needs to be validated.

HOWEVER, a correctly implemented DNS (direct numerical simulation) is more accurate than any experiment.

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Indeed, CFD and FEA are approximations requiring thousands or even millions of calculations for situations where analytical calculations aren't practical or can't deal with the detail. But for every critical FEA plot I run, I back it up with hand calcs for verification before complicating the model. Simply because the chance of a typo in any input is very real.

I'll get that intake model sorted for you today Ben. I've been sick.

For the record Jose has done it he has sent me a map that does all I want.
Very little smoke can drive the TD5 like a 4BD1 not like a 2 stroke motor bike.
This guys skills are exceptional.

Thank you Jose

So, with no more questions about A/F ratios and smoke. Lets look at what the TD5 can and can't do in relatively stock form.

Turbo diesel performance hangs entirely on boost and what boost can and cannot be produced by the turbo attached to it.

The stock turbo on a TD5 disco is a garrett GT2052S Model - 452239-0008.
The GT2052S model designation means it has a 52mm compressor wheel, a GT20 turbine and is wastegated.
Turbomaster have the whole parts listing here: Garrett Model GT2052S Repair List - 452239-0008 reference - Turbos - TurboMaster

The 52mm compressor wheels are available in many different trims to bias them towards either more airflow or more boost. Dig through the turbomaster build list above and the compressor wheel used is the 451584-0007.
Turbomaster are kind enough to also list all common garrett compressor wheels here with their measurements: Compressor Wheels - Garrett Racing - Applications - TurboMaster

Scroll down and we find the wheel in the TD5 has a 38.3mm inducer, which with the 52mm exducer works out to 55 trim.
Trim is the area ratio of inducer (intake) to overall diameter. Smaller trim wheels are suitable for higher boost, larger trim wheels are suitable for higher flow.

Garrett don't publish a compressor map for this exact compressor wheel, their 52 trim 52mm wheel is the closest. It is here:
https://www.aulro.com/afvb/images/im...13/09/1386.jpg

I'll plot out some operating points on it soon to show where the stock engine runs and what scope their is for more boost and airflow without exploding anything.

Just to recap.

Stock diesels run A/F ratios of around 20-22:1. A tuner can safely richen the mix to get a small increase in power and torque at the same boost level without melting anything.

The stock TD5 is 300Nm at 1950rpm and 100kw (disco) at ~4000rpm. The green points show where the required pressure and flow points sit on the compressor map:
https://www.aulro.com/afvb/images/im...13/09/1383.jpg

As you can see, the max torque point is right on the edge. There is no real scope to increase boost at that rpm with the stock turbo. The stock power point is in a good spot, with scope for a small increase in boost.

If you just increase fuel to gain more power and torque, you can get to ~360Nm and 115kw safely. This gives you a clean and safe tune that can be happily run with the foot flat for hours with no problems.
But you won't pass the Euro 2 and 3 tests the engine originally did.

The red point is showing boost raised to about 22psi where the engine can safely produce the power, but the turbo can't. It is off the compressor map. Sure you can make it happen, but there is a real risk the turbo will give you the finger and throw it's blades into your intercooler.
Same with the pink point for the boost and airflow required to sustain a safe and clean 140kw.