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Discussion Starter · #61 ·
Yeah, interested to see what you find. The cost /performance improvement of current tunes and mods has me scratching my head a bit.
Aus delivered cars don't have the particulate filter, are there other differences as well in the exhaust system?.
With the exhaust button on I find my A45s loud enough.
Our cars have the AMG performance exhaust as standard; however don't know the case in other markets.
Noise level is no where near as important as back pressure.
I could care less what it sounds like, (so long as I don't get stopped!! :)), so long as total system back pressure, as measured at the turbine outlet, is less than 0.5 PSI

i think it is probably true to say that our spec vehicles are as good as it gets for a standard, as delivered, A45S.

It will be months for me to obtain the data as outlined in my previous post, so please don't hold your breath.

In addition to the points listed, I am also going to need to monitor the fuel pressure at the tank mounted pump outlet and to the inlet port injectors, along with getting said injectors flowed.
At the end of the day, no point in bulk air, if there is problem with fuel volume delivery,
 

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Discussion Starter · #62 ·
And still upgraded turbo for an additional 5 hp.


Why don't you tell me what you find strange.

Well gpf cars should be able to make more than 6 hp once that thing gets out of the way. Not saying it's gonna be anything like S3 8p, MK6 Golf R, Edition 30 GTI etc whopping exhaust gains. BYD engine in specific (found in Edition 30 GTI / Pirelli Edition in Australia), 230 hp stock but every single one of them dynoed at no less than 240, made 310-320 at 100oct RON setting which may seem impressive for just a tune, but as it was a detuned version of S3 8p (265 hp stock) it was pretty much expected. What was truly impressive though, was the exhaust gains (plus hpfp and ic) to 370 hp. That's 50-60 hp gains from stage 1 to stage 2+ (there was also a stage 2 that involved keeping the stock hpfp but nobody kept it stock - you often had to upgrade anyway as it was already worn and not able to keep up with 135bar iirc). Nowadays hot hatches come off the factory with plenty of upgrades already, so you don't have to go far, like you said, you're already there. MQB gen for instance. MK3 Seat Leon Cupra (gpf version, 290 stock), makes 370 hp with just a tune at 100oct RON. Stage 2 does not involve an exhaust, just an intake, ic and a small tweak in the tune and you can make as much as 400 hp at 100oct RON. So we're talking stage 1 to 2 +30 hp as opposed to 60 of those older hot hatches. So it's obvious newer cars come off the factory at a significantly better state, where almost all additional power comes right off the bat with a tune.

Same thing with the A45s. Almost all power should come with the tune, however, I believe Euro spec A45s should make at least +20 hp with a 200 cell gpf-delete cat. There's no way that thing is only 6 hp restrictive.

As for the intake. I don't think intakes make much of a difference, but they do make some difference, in certain applications. Some tuners even require them, such as the case of the Seat Leon Cupra 290. And it's not a marketing thing, as you can get any intake you want, you don't have to buy their in house product. So it does something. In the context of the stock Turbo's Choke Flow I dunno, but mass flow definitely.
I need to make a correction to my Akrapovic comments.
1) It was just over 6KW, not 6 HP . so call it 8.5 HP
2) It was not for their 200 CPI downpipe, but rather their exhaust system. They make NO claims for increased power from their 200 CPI downpipe.
Which raises two new points.
What are they actually comparing to what? I really don't' know.
Either way, the actual power gains from what I think we can all agree is a high end product, are minimal.

Why is this so is just one of the many things which i want to understand before I start to seriously mod my vehicle,
 

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I need to resolve an issue with mine before pulling the trigger.

Dunno if you've read my posts but at WOT I've been getting hiccups at the top of 3rd or 4th gear and sometimes even sudden massive power drops, so intense it feels like you're hitting a wall. But other times it runs flawlessly. Definitely not fuel involved, that I'm sure of. Also doesn't feel like misfires. Today I did a few more runs and had no issues. Yesterday it was hiccups day. No check engine light no warnings no nothing which is weird for a car that will display a warning for pretty much anything; had a time de-synchronization error that occurred sometime during last year's lockdowns, after it was parked for close to two weeks in a basement garage with no reception, so when I took it out for a drive I got a check engine that was quickly resolved at the dealership. And yet no check engine for something that's definitely not normal?

One other thing I actually noticed today, is that if on that driving session it doesn't do anything, then it'll stay that way for the entire session. If I take the car and it starts acting up, it'll do so very early and will keep acting up for the entire session. Also, those times that'll run flawlessly, gear changes will be smooth as silk, I'm talking about changes during a run (Race mode, ESP-sport, Manual shifting just before redline). If gear changes feel rough and jerky, I'll most likely get hiccups too, and some times even a massive power drop.

Gonna get it scanned for errors some time later this month but I doubt it's gonna show anything.
 

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Discussion Starter · #64 ·
I need to resolve an issue with mine before pulling the trigger.

Dunno if you've read my posts but at WOT I've been getting hiccups at the top of 3rd or 4th gear and sometimes even sudden massive power drops, so intense it feels like you're hitting a wall. But other times it runs flawlessly. Definitely not fuel involved, that I'm sure of. Also doesn't feel like misfires. Today I did a few more runs and had no issues. Yesterday it was hiccups day. No check engine light no warnings no nothing which is weird for a car that will display a warning for pretty much anything; had a time de-synchronization error that occurred sometime during last year's lockdowns, after it was parked for close to two weeks in a basement garage with no reception, so when I took it out for a drive I got a check engine that was quickly resolved at the dealership. And yet no check engine for something that's definitely not normal?

One other thing I actually noticed today, is that if on that driving session it doesn't do anything, then it'll stay that way for the entire session. If I take the car and it starts acting up, it'll do so very early and will keep acting up for the entire session. Also, those times that'll run flawlessly, gear changes will be smooth as silk, I'm talking about changes during a run (Race mode, ESP-sport, Manual shifting just before redline). If gear changes feel rough and jerky, I'll most likely get hiccups too, and some times even a massive power drop.

Gonna get it scanned for errors some time later this month but I doubt it's gonna show anything.
That sort of intermittent error can literally drive both your and your dealership crazy.
As you say, you need to resolve it before proceeding.
I take it you have already put a new set of spark plugs in it?

Talk about these vehicles getting maybe TOO sophisticated, you remember I said I have had the nose cone off mine?
Now it has to go back to the dealer for ECU reset, just because the forward sensors in the nose had been disconnected.
My body guy had never previously seen even a Merc that he could not reset with his scan tool.
First time with our car!! :)
 

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I haven't but highly doubt it's spark related because I'm talking about a couple dozen flawless runs from 1st to 4th or 5th gear (where the problem typically occurs), in one single session. If it was the spark plugs, I would've noticed something. And yet other times I'll get hiccups in every single run. It's like I'm gonna have one flawless session, from engine start to shut down, or it's gonna be all hiccups (at WOT). Also used to think it might have something to do with engine and gearbox temps but as of yesterday it doesn't look like it, as my temps eventually climbed to 103°C and over 90°C respectively and yet the car kept hauling ass with zero issues. In another car several years ago I did have hiccups at one time, but it was caused by misfires which I could feel in the exhaust, it was entirely different, and it was the spark plugs (top of porcelain had turned brown) but the thing is, I had that all the time, in every single run, everyday, until I ruled fuel out and checked the plugs. Now I've already ruled fuel out and I'm on the brink of ruling temps out too, but as I said, there seems to be a pattern with the way it shifts. In those sessions that I get smooth gear changes everything's fine, when they are rough and jerky I'll get hiccups. It seems to me like the ecu is trying to protect the transmission.

I'm gonna start with the diagnostics and see what dealer says. But it's gonna be in a couple of weeks. Oh I am gonna get to the bottom, question is how much it's gonna cost me in fuel; yesterday I went through half a tank in test runs.
 

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Well, several members have reported all kinds of weird issues. I only know this, it's my first time to buy a car that's been out for two months. That's the price to pay I guess. I used to buy cars that were out for at least a year and never had too many issues, that's saying something. If anything, at least I was never a regular visitor at my dealership. Lesson learned.
 

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8534

8535

Perhaps I could suggest that you use a data logger to help you get a clear picture of what is going on.

During the early days of my car after it was tuned, occasionally the car runs less stronger but there wasn't any check light and I couldn't understand why it was so.

Hence, whenever I decided to do a wide open throttle run I would log the ECU via the OBD port and eventually we discovered that certain diagnostic tables were responsible for reducing the boost (to protect the engine I suppose) if it determines that it doesn't like what it is seeing from the various sensor inputs.

You could see that in the first graph, the ECU basically started to reduce boost gradually 3rd gear onwards and when I was done by the 5th gear the boost was reduced so much the car lost most of its "oomph" it felt much slower than usual.

We eventually made some adjustments and in the next graph, you could see that the boost curve is straight all the way until the end and it has been like that ever since.

I know that you car isn't tuned, but still with a logger it would still be able to help you see what is actually happening during the run as you could look at the various channels and determine whether there is something odd or out of the norm that could have caused the car not to behave like it should.
 

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Discussion Starter · #68 ·
View attachment 8534
View attachment 8535
Perhaps I could suggest that you use a data logger to help you get a clear picture of what is going on.

During the early days of my car after it was tuned, occasionally the car runs less stronger but there wasn't any check light and I couldn't understand why it was so.

Hence, whenever I decided to do a wide open throttle run I would log the ECU via the OBD port and eventually we discovered that certain diagnostic tables were responsible for reducing the boost (to protect the engine I suppose) if it determines that it doesn't like what it is seeing from the various sensor inputs.

You could see that in the first graph, the ECU basically started to reduce boost gradually 3rd gear onwards and when I was done by the 5th gear the boost was reduced so much the car lost most of its "oomph" it felt much slower than usual.

We eventually made some adjustments and in the next graph, you could see that the boost curve is straight all the way until the end and it has been like that ever since.

I know that you car isn't tuned, but still with a logger it would still be able to help you see what is actually happening during the run as you could look at the various channels and determine whether there is something odd or out of the norm that could have caused the car not to behave like it should.
Do I take it from your experience that the limit as set by various functions within the the ECU, is effectively 3.5 BAR absolute, (2.5 BAR Boost) except for permitted "flicks' on gear change?
 

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Do I take it from your experience that the limit as set by various functions within the the ECU, is effectively 3.5 BAR absolute, (2.5 BAR Boost) except for permitted "flicks' on gear change?
Perhaps when the two of you have settled the boost debate you can turn it in to english for the rest of us. My reading of this so far is that there is in fact a lot more than 10% headroom in the A45s.
 
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Do I take it from your experience that the limit as set by various functions within the the ECU, is effectively 3.5 BAR absolute, (2.5 BAR Boost) except for permitted "flicks' on gear change?
That is a question that only my tuner can answer, this log was from one of the calibration from the very early days when the car was being tuned.

I've stopped logging the car ever since the car has been running smooth.
 

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Perhaps when the two of you have settled the boost debate you can turn it in to english for the rest of us. My reading of this so far is that there is in fact a lot more than 10% headroom in the A45s.
I definitely think the same as you, but unfortunately I don't have 50 years of experience in the field to be able to prove it. Meanwhile I am just going to enjoy driving the car.
 

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I ask that "50 years of experience" become the forum's favorite quote.
 

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View attachment 8534
View attachment 8535
Perhaps I could suggest that you use a data logger to help you get a clear picture of what is going on.

During the early days of my car after it was tuned, occasionally the car runs less stronger but there wasn't any check light and I couldn't understand why it was so.

Hence, whenever I decided to do a wide open throttle run I would log the ECU via the OBD port and eventually we discovered that certain diagnostic tables were responsible for reducing the boost (to protect the engine I suppose) if it determines that it doesn't like what it is seeing from the various sensor inputs.

You could see that in the first graph, the ECU basically started to reduce boost gradually 3rd gear onwards and when I was done by the 5th gear the boost was reduced so much the car lost most of its "oomph" it felt much slower than usual.

We eventually made some adjustments and in the next graph, you could see that the boost curve is straight all the way until the end and it has been like that ever since.

I know that you car isn't tuned, but still with a logger it would still be able to help you see what is actually happening during the run as you could look at the various channels and determine whether there is something odd or out of the norm that could have caused the car not to behave like it should.
It's a good idea. Yours has a perfect interface btw, clear and easy to read. I used to have a VCDS cable for my previous cars, but only got it after the tune. I didn't think I was gonna need it in the A45s while still stock. Little did I know.
 

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Discussion Starter · #74 · (Edited)
I ask that "50 years of experience" become the forum's favorite quote.
Snide comments aside,
let me start to show you what ANY turbo experience will tell you:-

At the stock 2.1 BAR boost:-
Assuming 20C compressor Inlet Temps. which is probably a tad optimistic, even in the UK ! :)
Comp. Discharge Temp
Stock rated HP (65% AE) 180C
At the 60% efficiency line 195C
at the 55% efficiency line 215C
At the 50% efficiency line 240C

The problem is, I doubt ANY of the Tuners, Box or ECU recalibration, are running the stock 2.1 BAR boost.
I am waiting for answers to some questions I have asked; however I am going to bet that even at 10 to15% power increases, they are running 2.4 to 2.5 BAR.
This makes the above situation significantly WORSE.
When i have some Tuner boost figures, I'll re run the above temperature numbers.
Anyone who thinks this is acceptable, simply doesn't have ANY turbo experience, let alone 50 years.

Do we have a good intercooler system on our cars?
I believe so, although I have no data yet.
It will be interesting to see just how well it does cope with the above.
 

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More like 2.4 bar (gauge), there's more than just boost.
 

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Discussion Starter · #76 ·
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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Discussion Starter · #78 ·
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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Discussion Starter · #79 ·
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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Discussion Starter · #80 ·
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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