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Just to let you guys know I had a PM response to my question about the gearbox being a possible reason for the MB engine restrictions and he thinks it can take more power and torque. So it may well be the engine itself.
 

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It would be interesting to know from MB what the reason is as they are not doing the same to the A35. I'm guessing with the €1bn they spent on developing the rear multi-gear set up they have resolved any PTO problems.
 

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The main challenge of the PTO is the traversal layout of engine and gearbox, to derive a drive to send power to the rear you need to turn 90 degrees out of the gearbox hence why the PTO will always have a torque limit, even in the A45s.

Plus there the matter of slightly overdriving one axle (by a small amount, it’s not exactly 1:1) so the bevel gears will always be under strain of some sort.
 

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The main challenge of the PTO is the traversal layout of engine and gearbox, to derive a drive to send power to the rear you need to turn 90 degrees out of the gearbox hence why the PTO will always have a torque limit, even in the A45s.

Plus there the matter of slightly overdriving one axle (by a small amount, it’s not exactly 1:1) so the bevel gears will always be under strain of some sort.
I don't disagree that by the laws of physics the PTO will have a torque limit but can't understand why the A35 is not being treated the same way by MB.
 

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Because it’s not a highly strung 4-cyl engine compared with the M139 :p

We know there’s more headroom in that modified M260.

Guys,

ALL transmission components have a torque limit.
Does not matter whether it is the PTO / Gearset or any other component within the driveline.
( Even the half shafts, or CV joints at either end of them)
Our driveline is manufacturer (not AMG, another company) torque rated to 520 Nm.
However, transmission Engineers usually work on a 40% load rating to failure.
That also presumes total traction.
IE NO tire slip.
Therefore, as long as we apply sufficient clamp load to the clutch plates, we should be able to transmit around 730 Nm
Given I figure @changchewsoon is applying around 750 Nm, he is real world proof of this situation.
Although I have never asked him about wheel spin.
Would be interesting to know

The well documented W176 issues were related to the use of a 360 Nm rated drivetrain, having 450Nm + being applied.
IE AMG were well into using A LOT of the 40% safety margin, as delivered, standard.

My personal gearbox issue was related to the type of Dyno I was attempting to use, initially.
NOTHING to do with the box structurally. IE Applied torque.
It was related to the dyno confusing the transmission with different front/ rear axle speeds and affecting the selection process.

So, we are definitely back to the engine, which I never left, personally!! :)
Remember Brabus's home market is one of their biggest and they warrant most of their product.

If they have concluded after last Summer in Germany that they cannot warrant the "Tuned" A45s for extended WOT use at VMAX on the Autobahn, then their easiest solution is to simply stop selling the product.
 

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Re emissions it’s more nuanced than that.

DI is better for reducing CO2 emissions, but considerably worse than IDI for Particulate emissions (PN) hence why most other manufacturers use the IDI at part load to reduce PN.

Particulate Emissions is a huge problem with DI, the main reason why our cars are fitted with GPF in UK/EU & US (but not Aus!)
@veeeight
OK I have half the answer to the fuel system supply question.
I am having trouble getting the pump module flowed, as it is a brushless motor with a fixed regulator in the module and its output is controlled by a variable voltage output Pump Control Module.
Currently trying to determine if this is a seperate item or incorporated into something else, such as the CPC.

In any event, I do have the Injector / fuel rail answers.
1) The fuel rail does not restrict the injectors..
However, it is Dead Head" and thus the fuel obviously gets sufficiently hot in operation, that AMG felt it necessary to monitor it.
2) The injectors are KILLER!!
To describe them as "auxiliary" is definitely NOT doing them justice.
AT WOT, full load, differential fuel pressure of 4.6 BAR (6.7 BAR fuel pressure- 2.1 BAR boost), 100% duty cycle, they flow 820 cc /Min!!

Now, no car company likes to run 100% duty cycle and generally work on 75%, so call them 615 cc / min.

At a 12:1 A/F ratio, you need around 5 cc /min / HP.

So call them 120 HP per injector, although it is probably a little less given AMG are probably running somewhat richer than12:1 at WOT in order to save the Cat at V Max on the autobahn.

Even by OEM standards and their safety margins we are looking at upwards of 480 HP in total.
"Auxiliaries" ???
I am beginning to think my individual fuel flow meters are going to show zero flow to the direct injectors at WOT!!!
 

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Wow. Personally in terms of WOT power strategy I am averse to running any richer than around 12.4:1 but can only guess that AMG might be running even more simply to keep the temperatures down
 

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Wow. Personally in terms of WOT power strategy I am averse to running any richer than around 12.4:1 but can only guess that AMG might be running even more simply to keep the temperatures down
I am with you; however I have frequently seen 11:1 at WOT used by the car companies to protect the Cats.
Bringing the A/F back to your numbers is one of the common aftermarket Tuner 'tricks" to show improved power output.
I shall know for sure after data logging as I am installing wide band O2 sensors either side of the Cat.
 

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@veeeight
OK I have half the answer to the fuel system supply question.
I am having trouble getting the pump module flowed, as it is a brushless motor with a fixed regulator in the module and its output is controlled by a variable voltage output Pump Control Module.
Currently trying to determine if this is a seperate item or incorporated into something else, such as the CPC.

In any event, I do have the Injector / fuel rail answers.
1) The fuel rail does not restrict the injectors..
However, it is Dead Head" and thus the fuel obviously gets sufficiently hot in operation, that AMG felt it necessary to monitor it.
2) The injectors are KILLER!!
To describe them as "auxiliary" is definitely NOT doing them justice.
AT WOT, full load, differential fuel pressure of 4.6 BAR (6.7 BAR fuel pressure- 2.1 BAR boost), 100% duty cycle, they flow 820 cc /Min!!

Now, no car company likes to run 100% duty cycle and generally work on 75%, so call them 615 cc / min.

At a 12:1 A/F ratio, you need around 5 cc /min / HP.

So call them 120 HP per injector, although it is probably a little less given AMG are probably running somewhat richer than12:1 at WOT in order to save the Cat at V Max on the autobahn.

Even by OEM standards and their safety margins we are looking at upwards of 480 HP in total.
"Auxiliaries" ???
I am beginning to think my individual fuel flow meters are going to show zero flow to the direct injectors at WOT!!!
Further to our fuel pump, it is apparently frequency modulated and given MB Australia will tell me nothing, I am going to have to scope the pump running in my car and then acquire or borrow a frequency generator to simulate its operation on the fuel flow bench.
****, NOTHING is easy on this vehicle!! :)
 

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Guys,

ALL transmission components have a torque limit.
Does not matter whether it is the PTO / Gearset or any other component within the driveline.
( Even the half shafts, or CV joints at either end of them)
Our driveline is manufacturer (not AMG, another company) torque rated to 520 Nm.
However, transmission Engineers usually work on a 40% load rating to failure.
That also presumes total traction.
IE NO tire slip.
Therefore, as long as we apply sufficient clamp load to the clutch plates, we should be able to transmit around 730 Nm
Given I figure @changchewsoon is applying around 750 Nm, he is real world proof of this situation.
Although I have never asked him about wheel spin.
Would be interesting to know

The well documented W176 issues were related to the use of a 360 Nm rated drivetrain, having 450Nm + being applied.
IE AMG were well into using A LOT of the 40% safety margin, as delivered, standard.

My personal gearbox issue was related to the type of Dyno I was attempting to use, initially.
NOTHING to do with the box structurally. IE Applied torque.
It was related to the dyno confusing the transmission with different front/ rear axle speeds and affecting the selection process.

So, we are definitely back to the engine, which I never left, personally!! :)
Remember Brabus's home market is one of their biggest and they warrant most of their product.

If they have concluded after last Summer in Germany that they cannot warrant the "Tuned" A45s for extended WOT use at VMAX on the Autobahn, then their easiest solution is to simply stop selling the product.
Thanks for the rundown. I would guess quite a few of our engines hit the 520Nm as the on paper spec is 500Nm. What you say makes a lot of sense. I won't ask how you worked out @changchewsoon is running 750Nm, it's probably somewhere in the small print of this thread :)
 

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Clearly the idea was to offer the enthusiasts an out of the box tuned car, hence the very limited headroom and the overprotective systems, which I've never seen before. They were like we know you're gonna go down the tuning route, let us do it for you, the professional way. But we'll keep an eye on you 24/7 because you won't be tuning this car. That said, it may be true that no car maker designs a car based on the assumption that the owner is going to tune it, but still they often provide plenty of headroom such as in the case of MK6 and MK7 Golf R and their siblings, although the crown belongs to my Edition 30 GTI, 230hp stock (dynoed 240hp), and compressor map running all the way to 370hp. Now that's headroom! Going into overspeed (adding an aftermarket wg) we could make up to 420hp on w/m and 390hp without it (but strictly on 100 RON fuel). And that's on stock turbo. And you didn't have the computer up your ass either. You could argue back in 2007 the electronics weren't as sophisticated, but still, we weren't lacking safety systems; I've had the car go into limp mode a couple of times. So what I think AMG was thinking is let us build it for you, but they wouldn't go the extra mile without a million sensors around the car. Slap that CPC in as well and enjoy your tuned car.
 

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Thanks for the rundown. I would guess quite a few of our engines hit the 520Nm as the on paper spec is 500Nm. What you say makes a lot of sense. I won't ask how you worked out @changchewsoon is running 750Nm, it's probably somewhere in the small print of this thread :)
It seems that the standard applied pressure to the clutch plates copes with around 550 Nm without trouble.

By the time you approach 600Nm, you need two things, as @changchewsoon has already proven.
1) Alteration to the the max torque threshold as set within the CPC
2) Increased clutch plate clamp pressure which apparently can be accessed within the engine ECU.
IE you don't need to access the TCU

Self evidentially, to achieve the preceding one requires both the correct software AND a knowledgeable Tuner.
It would appear @changchewsoon has both.

As for @changchewsoon's engine's torque output, even though he does not have access to a Maha MSR500, he has provided sufficient data for me to be sure of his number within a 5% margin of error,
 

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Clearly the idea was to offer the enthusiasts an out of the box tuned car, hence the very limited headroom and the overprotective systems, which I've never seen before. They were like we know you're gonna go down the tuning route, let us do it for you, the professional way. But we'll keep an eye on you 24/7 because you won't be tuning this car. That said, it may be true that no car maker designs a car based on the assumption that the owner is going to tune it, but still they often provide plenty of headroom such as in the case of MK6 and MK7 Golf R and their siblings, although the crown belongs to my Edition 30 GTI, 230hp stock (dynoed 240hp), and compressor map running all the way to 370hp. Now that's headroom! Going into overspeed (adding an aftermarket wg) we could make up to 420hp on w/m and 390hp without it (but strictly on 100 RON fuel). And that's on stock turbo. And you didn't have the computer up your ass either. You could argue back in 2007 the electronics weren't as sophisticated, but still, we weren't lacking safety systems; I've had the car go into limp mode a couple of times. So what I think AMG was thinking is let us build it for you, but they wouldn't go the extra mile without a million sensors around the car. Slap that CPC in as well and enjoy your tuned car.
@Theo
The crux of your post is in your last phrase, "enjoy your tuned car".

The point is where and how. (you enjoy it, I mean)
I'll just give you two extremes to make my point.

One guy uses his tuned A45S in the UK to run the occasional SS 1/4 mile and 100 to 200 KPH blasts, the later usually at night.
This car is unlikely to ever demonstrate any issues, so long as a reasonably competent Tuner undertook the work.

The other guy uses his tuned A45S in Australia to run the occasional standing mile during the day, (35C +) and 100 to 200 KPH blasts the later usually at night.
This engine's likely life?
Well, not the same as the vehicle in the UK, that I can guarantee you!!

The cost of replacement of a blown M139 is DEFINITELY going to take the "enjoy" out of enjoyment !!! :)
 

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@Turbo Ed - did you have any issue with MB replacing your gearbox if the damage was done by the dyno?
They knew it happened on a Dyno, just not the TYPE of dyno and I did not enlighten them.

Their primary concern was that the vehicle was standard and it certainly was at the time damage occurred.

NOTE Do not use a HUB dyno on our vehicle.
 

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They knew it happened on a Dyno, just not the TYPE of dyno and I did not enlighten them.

Their primary concern was that the vehicle was standard and it certainly was at the time damage occurred.

NOTE Do not use a HUB dyno on our vehicle.
I'm surprised MB didn't dig further. Maybe they don't know what we know about a HUB dyno. There are videos on line of people just going and buying them. Getting some training and taking them home on trailers.
 

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I'm surprised MB didn't dig further. Maybe they don't know what we know about a HUB dyno. There are videos on line of people just going and buying them. Getting some training and taking them home on trailers.
To be fair to the workshop involved, they are one of the top five reputationally in my city and have 100,000 Pounds Sterling worth of HUB dyno in a 50,000 Pounds Cell

My major complaint is that I queried them extensively, (I am sure you can imagine!! :)) BEFORE they started the work, regarding front/ rear absorber "linkage"
They assured me it was done electronically. (As it is obviously not mechanical)
So, they either lied or were ignorant.
Not good either way.
 

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Sorry I've been out of action lately due to work, and wow at least a few pages of this thread I needed to read to catch up on what was missing!

@Turbo Ed glad to see that you finally gotten your car back and it seems like you've already done quite a bit of work on it! I've seen a couple of GR Yaris in my country and they're really fast too! Yes I have a 500 whp Yaris myself and it still gives me over 400 KM of mileage on a full tank.
 
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