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More like 2.4 bar (gauge), there's more than just boost.
There had better be more than just boost!! :)

However, I am not sure to what you are referring.
1) Compressor discharge temps?
Then, no you are wrong, it IS just boost and compressor efficiency (along with compressor inlet temp from which you start, of course)
I agree with you about the 2.4 BAR number, as that is what I have also been told and shall re run the numbers on that basis. (I'll post those separately)
OR
2) Tuning, overall?
Well, yes, there is obviously more than simply boost; however when you cut out all the considerable tuning work necessary to "avoid", "get around" or "negate" all the fail safes the OE's have instigated in an attempt to prevent us from doing any of this, it all comes down to Ignition advance and Air/fuel ratio. (Not discussing drivetrain, of course, just the engine)
OR
3) Eventual Power Output
Now, this is the interesting one and I hope the one to which you were referring in your cryptic response, as this is the subject which brought me onto the forum in the first place.
I want to know, where is the missing 200 BHP?
 

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I was not told of anything as I didn't ask anyone, just based on my outrageously less than 50 years of experience in tuning cars. 2.4 bar should get us that +50 hp. 3.4 and 3.5 bar is absurd I dunno how that came out.

The other thing I said was that there's a lot more into tuning than just boost, but then you already know that. I dunno what kind of firewalls have been in place, but I have yet to see a tune that's only about boost. It's gotta be a very shitty one, if there is one. Probably one that you really will find wrapped up in a rag of cloth at your local flea market, as I was saying on that other thread.
 

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More like 2.4 bar (gauge), there's more than just boost.
Ok here are the compressor discharge numbers at 2.4 BAR boost, assuming 20C compressor inlet temps.

60% efficiency line 215C This is where you are at on the map at 465 HP. (Or, approx. 10% increase over stock)
55% efficiency line 235C
50% efficiency line 260C

Regarding our Intercooler system and resultant engine inlet manifold temps, again with 20C compressor inlet temps, the stock setup results in the following:-

Compressor discharge 180C
inlet manifold temp 50C
So a drop across the Intercooler of 130C

This temp drop will NOT improve as mass flow across it increases, (due to increased power).
It will, if anything, remain the same or actually decrease, depending obviously upon intercooler capacity.

In other words, even at only a 10% power increase, using the stock turbo and intercooler, the inlet manifold temp (at a 20C ambient) will be of the order of 215C-130C = 85C

Don't think this matters, as compared to the stock 50C inlet manifold temperature? IE a 35C difference?

Well, every 6C is worth around 1% in power, so we are looking at a 6% power loss. relative to what could be achieved by simply maintaining stock levels of efficiency.
Personally, I am hoping that it will be possible to improve on the stock levels of efficiency, as I think it should be possible to do better than the 130C temp drop over the stock intercooler.

In any event, I certainly don't want to go backwards, in terms of overall system efficiency, that is for sure.

Elements like this all contribute to the missing 200 HP
 

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I was not told of anything as I didn't ask anyone, just based on my outrageously less than 50 years of experience in tuning cars. 2.4 bar should get us that +50 hp. 3.4 and 3.5 bar is absurd I dunno how that came out.

The other thing I said was that there's a lot more into tuning than just boost, but then you already know that. I dunno what kind of firewalls have been in place, but I have yet to see a tune that's only about boost. It's gotta be a very shitty one, if there is one. Probably one that you really will find wrapped up in a rag of cloth at your local flea market, as I was saying on that other thread.
I don't think anyone is talking about 3.4 an 3.5 BAR BOOST numbers.
If those numbers were mentioned they would Pressure Ratios, or perhaps ABSOLUTE pressure numbers, as some data logging measures that way.

Of course, you are correct, a 2.4 BAR Boost figure , with the correct complimentary tuning, should certainly result in at least a 10% power increase (i.e. 40HP) and probably slightly more, depending upon how overly rich the stock A/F's are set at WOT by MB to protect their Cat matrix,
 

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I don't think anyone is talking about 3.4 an 3.5 BAR BOOST numbers.
If those numbers were mentioned they would Pressure Ratios, or perhaps ABSOLUTE pressure numbers, as some data logging measures that way.

Of course, you are correct, a 2.4 BAR Boost figure , with the correct complimentary tuning, should certainly result in at least a 10% power increase (i.e. 40HP) and probably slightly more, depending upon how overly rich the stock A/F's are set at WOT by MB to protect their Cat matrix,
Sorry Theo, just seen my previous typo.
Apologies, but this is what happens when I am switching backwards and forward between compressor maps, which are notated in pressure ratios and Boost figures for general discussion.
I shall edit it immediately,
 

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No problem. To be honest for a second I did think you meant to say 2.4 - 2.5 as at 3.5 the turbo would be shot into orbit.
 

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Well The DTUK box arrived today. I was a bit concerned looking at the hardware as it had no model reference on it but on reading the instructions, I can see that they're specific to our cars.

I guess the hardware is generic and they just flash each box to match the order. View attachment 8549

Iain at Litchfield is happy to fit it for me, just need to see if I can squeeze it onto the Maha...

Any news yet on fitting,
 

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Any news yet on fitting,
Still trying to sort it... Iain hasn't got back to me with a date nor a quote for before and after dyno.

I'll give him a chase on Monday but am then running up against the arrival of my Akra with a different garage. If Litchfield don't come through will have my Akra guy fit the box while its up on the ramp for the exhaust.
 

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Depends on who your asking.
 

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So in summary 465bhp is the limit?
Depends upon many factors; however NOT just who you are asking.

Probably the single most important factor being, your personal risk / benefit analysis.

THIS will certainly depend upon who you ask, that is for sure.
What one person thinks in this regard can certainly vary to another.

Just think about the following:-
1) Our cars, standard, run, if not the highest boost level for a production gasoline powered vehicle, it must be close to it, at 2.1 BAR gauge, or 30.45 PSIG.
2) Even to achieve 465 HP, every Tuner i have been able to get to admit to what they do, acknowledges increasing this to at least 2.4 BAR, or 34.8 PSIG.
3) Even this increase in power, using the standard turbo, will increase the air temperature in the inlet manifold by a minimum of 35C. (or 70%)
4) To attempt to increase the power beyond 465 HP on the standard turbo, simply makes the above situation, worse.(Not to mention, over revs the turbo)

Now, only you can decide whether you want to do that to your own vehicle, no one else,
 

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Depends upon many factors; however NOT just who you are asking.

Probably the single most important factor being, your personal risk / benefit analysis.

THIS will certainly depend upon who you ask, that is for sure.
What one person thinks in this regard can certainly vary to another.

Just think about the following:-
1) Our cars, standard, run, if not the highest boost level for a production gasoline powered vehicle, it must be close to it, at 2.1 BAR gauge, or 30.45 PSIG.
2) Even to achieve 465 HP, every Tuner i have been able to get to admit to what they do, acknowledges increasing this to at least 2.4 BAR, or 34.8 PSIG.
3) Even this increase in power, using the standard turbo, will increase the air temperature in the inlet manifold by a minimum of 35C. (or 70%)
4) To attempt to increase the power beyond 465 HP on the standard turbo, simply makes the above situation, worse.(Not to mention, over revs the turbo)

Now, only you can decide whether you want to do that to your own vehicle, no one else,

Hi what do you think of these,

Performance chips – Chip tuning by RaceChip for MB A-Class (W177) A45 S AMG (310KW) | RaceChip

Extra 69hp its saying??
 

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I think this particular German company, (of whom I have known for some years) has a flair for marketing.
I would start by requesting before/ after, on the same vehicle, dyno run sheets, as tested on a Maha dyno.
( Not marketing department redraws, the original graphs as come off the Printer connected to the Dyno.)
They are German, (as is Maha), so a more than reasonable request, I would have thought?

Given you are in the UK, if I was looking for a Tuning Box, I think I would go with a DTUK box.
a) Their 470 HP claim seems quite reasonable and essentially as safe as any of this product can ever be.
b) They appear to be a rebranded, British version of the most reputable of the German Tuning box companies, DTE, whose claims, are not surprisingly, basically identical.
c) Given they are local to you, hopefully verification of DTUK's claims is not as difficult as I suspect will be the case if you request it from Race Chip in Germany.
 

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Now booked in at Litchfield for the 24th with before and after dyno runs on the Maha
 

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Now booked in at Litchfield for the 24th with before and after dyno runs on the Maha
Whilst dyno charts can be useful, I personally prefer vbox pbox dragy numbers, as well as how the car drives, drivability at low speeds etc. which a dyno chart can’t give.
 

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I have a Dragy so no problems with getting some before and after timings. The box will be fitted while I wait, less than an hour so the full Maha will depend on whether its available
As you're taking the car in next week it would be good to see what the pre-tuned version can achieve while you can still time it.
 

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Whilst dyno charts can be useful, I personally prefer vbox pbox dragy numbers, as well as how the car drives, drivability at low speeds etc. which a dyno chart can’t give.
Respectfully, I disagree.

What I think we all want to see is the measured increase in power and this can ONLY be done on a quality chassis dyno with a skilled operator on the same vehicle on the same day.
Which nn7man has extremely kindly organised to have done.
We should all be very grateful to him.

While your On-Road test requests are very valid and completely understandable, the results of this sort of work can be very misleading.
It is no accident that the men (and increasingly women) who do this sort of On-Road back to back evaluation for a living are both highly skilled and consequently, well paid!! :)

Definitely not something I would claim to be able to do and with all due respect, unlikely, (although admittedly, not impossible) to be accurately undertaken by the general enthusiast.

So then completely unintentionally, one ends up with misleading results.

Definitely much safer to assess the value of any tuning work on a quality chassis (rolling road) dyno with a skilled operator,
 

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To get a drivable car, you need both.

Dyno charts can’t give that all important 0-60/62 pub bragging launch time, nor can’t tell you if it can actually put down all that power through the rubber on the road at launch (there are many tuned cars out there that can’t actually utilise their tune at launch).

There are plenty of wonderful looking gains on Dyno charts, but cars that are just completely undrivable in terms of daily use. Kangarooing, mysterious low speed drivability issues, flat spots, terrible throttle responses.

Believe me, I’ve over 50 years in the automotive industry. :p
 

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Respectfully, I disagree.

What I think we all want to see is the measured increase in power and this can ONLY be done on a quality chassis dyno with a skilled operator on the same vehicle on the same day.
Which nn7man has extremely kindly organised to have done.
We should all be very grateful to him.

While your On-Road test requests are very valid and completely understandable, the results of this sort of work can be very misleading.
It is no accident that the men (and increasingly women) who do this sort of On-Road back to back evaluation for a living are both highly skilled and consequently, well paid!! :)

Definitely not something I would claim to be able to do and with all due respect, unlikely, (although admittedly, not impossible) to be accurately undertaken by the general enthusiast.

So then completely unintentionally, one ends up with misleading results.

Definitely much safer to assess the value of any tuning work on a quality chassis (rolling road) dyno with a skilled operator,
Respectfully, I disagree.

You seem completely oblivious to the existence of a central powertrain controller (CPC) that exists in the car which basically monitors and controls the output of the power/torque the engine is making. It has a counter that keeps track of the number of times the excess power/torque is violated and basically it sends a signal to the ECU to reduce power to keep it in check.

Whatever figures that you're making on the dyno (after putting the car in dyno mode) where the CPC doesn't interfere is not going to be able to be fully utilised once you get out of dyno mode and when you're actually on the road doing a roll, unless you have your CPC remapped to have the torque limiters raised.

Which is also why vbox, pbox, draggy numbers are one of the many measurements to indicate how well the car actually performs on the road, because it also factors in slope in the measurement, at the same time showing the temperature, elevation and air density etc which all affects the actual performance on the car.

Nobody is asking one to put their lives at risk if they want to do a non-dyno quality measurement of a tuning work.

But again, what do I know. I do not have 50 years of experience like you do so please feel free to chip in if you think you have a better assessment on this.
 
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