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Really? Oh my please pardon my ignorance. I certainly am not aware of any device that is able to identify the terrain, track conditions or the car's drag coefficient! Maybe you could point us in the right direction?
So long as the tester states terrain and track conditions, (and the Russians did indicate same), that is good enough for amateur discussions.
Aero is irrelevant in this particular case as we are all discussing the same vehicle, so variances wouldn't be significant.

However, I'll tell you what IS significant.

Vehicle mass.
At 125 MPH
1450 KG is equivalent to 485 HP, which one would hardly consider amazing
However, at
1640 KG (my car) it would be equivalent to 555 HP, which one would have to consider entirely extraordinary .

I suspect the truth is somewhere in between; however we shall never know without the actual vehicle mass, shall we?
 

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So long as the tester states terrain and track conditions, (and the Russians did indicate same), that is good enough for amateur discussions.
Aero is irrelevant in this particular case as we are all discussing the same vehicle, so variances wouldn't be significant.

However, I'll tell you what IS significant.

Vehicle mass.
At 125 MPH
1450 KG is equivalent to 485 HP, which one would hardly consider amazing
However, at
1640 KG (my car) it would be equivalent to 555 HP, which one would have to consider entirely extraordinary .

I suspect the truth is somewhere in between; however we shall never know without the actual vehicle mass, shall we?
Oh you're saying all these info is now good enough for amateur discussions? Well, the same can be said about the weight as well then.

So then why the need to specify the weight or else it is considered irrelevant?

Unless you're now cherry picking what you think is significant and what is not to your own convenience? ;)

Users who use the GPS based measuring devices comprises of amateurs and serious professionals all over the world. You called everyone who didn't factor in weight being pointless and silly so I want to call you out on this.

Back to the Russians, the only information stated by them are vague information on the tune, hardware mods, fuel, dyno used, temperature, elevation and density air from the Dragy application which gets the information via GPS signal and external sources of temperature info as the unit itself doesn't have a temperature sensor built in.

They did not state whether the car has CPC nor TCU flash. So we can either assume that the car doesn't and it is still stock, or we can just say they are just being pointless and plain silly just like how you put it.

The same can be said for the weight as well, if they didn't state it, we can just assume it is the stock weight or we can just say they are just being pointless and plain silly just like how you put it as well.

So again, why the need to specify the weight or else it is considered irrelevant? Why not everything?

Come on, you can do better than this. You came in to the forum announcing you have over 50 years of experience. Anyone who doesn't factor in weight in their time measurement are all being pointless and silly like you said.

So once again, how can we all have large enough samples of data and turn this a lab precision small deviation margin of error confidence?
 

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Oh you're saying all these info is now good enough for amateur discussions? Well, the same can be said about the weight as well then.

So then why the need to specify the weight or else it is considered irrelevant?

Unless you're now cherry picking what you think is significant and what is not to your own convenience? ;)

Users who use the GPS based measuring devices comprises of amateurs and serious professionals all over the world. You called everyone who didn't factor in weight being pointless and silly so I want to call you out on this.

Back to the Russians, the only information stated by them are vague information on the tune, hardware mods, fuel, dyno used, temperature, elevation and density air from the Dragy application which gets the information via GPS signal and external sources of temperature info as the unit itself doesn't have a temperature sensor built in.

They did not state whether the car has CPC nor TCU flash. So we can either assume that the car doesn't and it is still stock, or we can just say they are just being pointless and plain silly just like how you put it.

The same can be said for the weight as well, if they didn't state it, we can just assume it is the stock weight or we can just say they are just being pointless and plain silly just like how you put it as well.

So again, why the need to specify the weight or else it is considered irrelevant?

Come on, you can do better than this. You came in to the forum announcing you have over 50 years of experience. Anyone who doesn't factor in weight in their time measurement are all being pointless and silly like you said.

So once again, how can we all have large enough samples of data and turn this a lab precision small deviation margin of error confidence?
I consider a possible variation in the developed power from 485 to 555 HP, to be highly significant, from a number of perspectives.
The problem is that the "stock" quoted weight, (by MB) varies by around 100 KG, depending upon spec., and if the Russians were serious about running a hot number, seat removal (around another 100KG all up) is pretty straight forward.
So there is no way to "guess" at what actual weight they were running.
I am not debating how they went about tune, hardware mods etc. That is an entirely separate discussion.

What i am trying to get through to you, is that without vehicle mass, any meaningful discussion about their results, (NOT how they achieved them), is actually impossible.
We currently have no way of knowing whether the results of their mods were simply average, absolutely spectacular, or somewhere in between.

Which we would have known, if we knew the mass.

Almost none of the other variables you have been discussing will have any significant effect on the 1/4 mile Trap Speed / Weight / HP equation.

The worst case by location would probably be where you are yourself. IE Moderately high ambient with high humidity.
You would simply Trap at a lower speed, indicating less HP, which I presume you would expect.
So long as you stated same, no foul.

It is one of the beauties of this particular calculation.
Unlike 1/4 mile ET's, (which are subject to almost every one of your mentioned variables) Trap speed is basically weight / power / speed and distance.

Like I said at the start of this, ANY serious car enthusiast SHOULD know the actual weight of his vehicle, (not guessed) for two reasons
1) It is the simplest. cheapest piece of data you will ever obtain on your vehicle.
2) It has such a profound effect on vehicle performance.

Without it, everyone is guessing.
Which I know I described as pointless, since, to me anyway, guessing in this game, IS pointless.
 

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I consider a possible variation in the developed power from 485 to 555 HP, to be highly significant, from a number of perspectives.
The problem is that the "stock" quoted weight, (by MB) varies by around 100 KG, depending upon spec., and if the Russians were serious about running a hot number, seat removal (around another 100KG all up) is pretty straight forward.
So there is no way to "guess" at what actual weight they were running.
I am not debating how they went about tune, hardware mods etc. That is an entirely separate discussion.

What i am trying to get through to you, is that without vehicle mass, any meaningful discussion about their results, (NOT how they achieved them), is actually impossible.
We currently have no way of knowing whether the results of their mods were simply average, absolutely spectacular, or somewhere in between.

Which we would have known, if we knew the mass.

Almost none of the other variables you have been discussing will have any significant effect on the 1/4 mile Trap Speed / Weight / HP equation.

The worst case by location would probably be where you are yourself. IE Moderately high ambient with high humidity.
You would simply Trap at a lower speed, indicating less HP, which I presume you would expect.
So long as you stated same, no foul.

It is one of the beauties of this particular calculation.
Unlike 1/4 mile ET's, (which are subject to almost every one of your mentioned variables) Trap speed is basically weight / power / speed and distance.

Like I said at the start of this, ANY serious car enthusiast SHOULD know the actual weight of his vehicle, (not guessed) for two reasons
1) It is the simplest. cheapest piece of data you will ever obtain on your vehicle.
2) It has such a profound effect on vehicle performance.

Without it, everyone is guessing.
Which I know I described as pointless, since, to me anyway, guessing in this game, IS pointless.
Ah, so you're too in the guessing game just like the rest where you're adamant on the weight where anyone who isn't is just being pointless.

That's disappointing albeit entertaining as I was expecting more from someone with the claimed years of experience to have more to back it than just because he states it and thinking that is the fact.

Okay, please carry on then! (y)
 

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Ah, so you're too in the guessing game just like the rest where you're adamant on the weight where anyone who isn't is just being pointless.

That's disappointing albeit entertaining as I was expecting more from someone with the claimed years of experience to have more to back it than just because he states it and thinking that is the fact.

Okay, please carry on then! (y)
No definitely NOT in the guessing game. EVER. ( Over 50 years!! :))
I really don't understand your comment here, sorry,

Hence the Dyno work I am about to undertake on various types of machine and the results which I shall subsequently post..

After that work, then the data I intend to pull from our engine and shall also post.

NEVER guess, always measure.

Happy for you to use that phrase to describe me!! :)
 

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No definitely NOT in the guessing game. EVER. ( Over 50 years!! :))
I really don't understand your comment here, sorry,

Hence the Dyno work I am about to undertake on various types of machine and the results which I shall subsequently post..

After that work, then the data I intend to pull from our engine and shall also post.

NEVER guess, always measure.

Happy for you to use that phrase to describe me!! :)
It sounds guessing to me but again, if you are saying you're not, you're not.

Okay, looking forward to see how your car does.
 

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And thanks for all the knowledge you've shared. I'm still boggled by that 10% of headroom and I'm not the only one, but I can't argue about things of which I have zero knowledge. And I guess time will tell whether all these cars running 470+ HP tunes (which is the majority) will remain reliable in the long term. I believe they will be.
[/QUOTE]

Theo, (et al)
Let's talk about Rolling Roads. (Love that so English expression!! :)
Going to be an encyclopaedia, so buckle in!
Before I start, some short personal CV so you know the basis on which I am writing.
Hate for you to think I was just " guessing"!! :)

1) Dyno Dynamics.
In 1995 I was the Technical Manager who specified and oversaw the commissioning of, the first commercial AWD DD machine.
(They had built a smaller, non commercial "Proof of Concept" machine for a local Technical college, immediately prior to our machine)
2) Mainline
Around 2012, by then as GM, I signed off on and oversaw my replacement as Technical Manager's complete conversion of the original DD machine to Mainline.
IE We refurbished and retained the original DD bed; however, the entire control system was now Mainline.
3) DynoJet and their erstwhile US competitor, Mustang Dynos.
From the early 90's until the GFC in 2008, I spent literally months in any given year, working with workshops in the USA, using both of these machines.
4) Maha
Almost no experience at all and absolutely none on the MSR500, which in my view, is really the first performance orientated AWD dyno which the company has offered.
They definitely HAD AWD dynos before the MSR500, which I have seen, however from my observations they had not been intended by their manufacturer to be used in performance work.

So, to start.
A lot of the differences which I am about to outline are regional in origin and it is definitely when one region's approach clashes with another, that confusion occurs.
What's more, I cannot overemphasise the absolutely critical requirement to always use exactly the same dyno for all performance development work.
Not even two different workshops with the same brand/ model of machine.
It needs to be exactly the same machine, every time.

AUSTRALIA
In Dyno's generally, not just AWD, DD ruled the market from the 80's until the late 00's.
Mainline got serious as a competitor during the 00s and by around 2010 definitely had superior controls, (Hence the swap which we did)
However, the data provided to the customer had been defined by the Chief Engineer at DD , many years' before and Mainline simply had to fall in line to compete.
That DD individual was strongly of the view that there was no accurate method to extrapolate Engine Power, from numbers measured at the tyres.
So, Australia's performance dyno market developed as Tyre Power measurement market, period.
No one ever talked anything ese.
Both DD and Mainline concentrated on building Tyre Power measurement dynos of ever increasing capacity.
When they both had 2WD units more or less measuring around 2,000 HP at the tyres, they ran into the predicable traction problems and started offering Hub Dynos, to address the issue.

This situation could have remained like this for ever, except for one thing.

In 2002 and again in 2004 I personally conducted an in depth, (weeks on each occasion) investigation of the UK's AWD Dyno equipped performance Tuning industry. (We were looking for potential UK Distributors Customers for our performance product).
That is where / when I saw Maha's predecessor to the MSR500.
Now, I am not going to write in detail on a predominantly UK site, on what I saw / concluded from those two trips, (if you are interested in detail, PM me) except to state the following facts.
1) There were approx.15 AWD Maha, mostly quite old, and none fit for purpose, in the UK, servicing a market of 60M.
2) In Australia at the same time, there were over 50 AWD dynos servicing a market of 20M. (Today there are over 200, between DD and Mainline, although the population has risen to 25M )

As we were quite close commercially at the time, I reported same to the then management of Dyno Dynamics.

UNITED KINGDOM
As a result of my reports, DD saw the obvious commercial opening.
By 2006 they had their first AWD dyno in service in the UK.
Between then and 2014 when Lichfield chose the first Maha SR500 sold in the UK, I don't know how many DD (and later I believe Mainline also) Australian AWD dynos went into the UK; however I believe a relatively significant number.
In addition, DD in particular, started to make sales in Europe. Perhaps not Germany itself, but definitely places like the Czech Republic, Poland, Italy, Scandinavia, etc.
However, both the Aussies had a marketing problem, didn't they?
Both in the UK and Europe generally, the performance market were accustomed, even then, to talk Engine Power, as that was the normal data provided, (who knows with what real accuracy) by the predecessor to the MSR500.
I am absolutely mortified to have to admit, that as Litchfield quite rightly and very politely outlines on their website (in their rationale of their 2014 Maha MSR500 purchase), that the Aussies cheated and took the technically simple way out.
Remember, they did not need Engine Power for their principal volume home market.
They were selling a handful of units into the UK / Europe, and 10's into the low 100's in their home market, where nobody talked Engine Power.
So, what did they do?
As Litchfield obviously identified at the time, they simply applied a percentage loss number within the electronic controls, which required no real re-engineering of the equipment.

The problem is, this is NOT correct and the driveline loses are NOT a fixed percentage of the power as measured at the wheels.
Simple to do electronically; however technically WRONG.

Which is precisely WHY I said to you on the other thread, if you have ever seen ANY real correlation between Engine Power as measured on either of the Aussie Dynos and a MSR500, it was simply a fluke, nothing more.

Basically the Aussie Dynos are excellent Tyre Power measurement devices, not Engine Power.

Whether the Maha MSR500 is as good at providing legitimate Engine Power numbers as most Brtish.and Europeans Tuners say it is, I look forward to seeing for myself as my personal project proceeds. The fact that there is actually one in my city, certainly at least makes this practical.

USA
I think I have written more than sufficient to this point, don't you?? :)
However, if you want to hear about the biggest joke in the legitimate Tuning world, being the "Drum of Concrete" ( DynoJet), just ask and we can continue on.
 

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@Turbo Ed Please do me a favor and have a look here. This is a CLA45s running under 500hp as the owner says. Are you saying the 70kg lighter A45s would need to have somewhere around 555 to trap just 3-4 mph higher? Honestly, comparing the two results, the Russian car don't look stripped to me. But it could be running just over 500hp.
 

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Theo,
LOL!!
No, that is NOT what I said.

I said if the car weighs what mine does, IE 1640 KG, it would need 555HP to run 125 MPH in the quarter.
At the other end of the spectrum, if the Russian car was built on a stripper, as is available in Europe, (but not UK or Australia) and then they took out the rear seats and front passenger seat (which you would NOT be able to see in their video), it would probably end up around 1450 KG and only need around 485 HP to run 125 MPH in the quarter.

THEN I said, the truth is probably somewhere in the middle.

Which IS the most likely case.
It PROBABLY has around 500 HP, or a little more and weighs somewhere between 1500 and 1550 KG.
Yes, the Tune is set on "KILL" but hey, you know those crazy Russians!!!
One thing for sure, on their roads, (on which I have driven), no one is holding WOT for any serious length of time!! :)
Autobahns they are not!!

However, NONE of the above was the point I was trying to make.
I was trying to use this case as an example of why KNOWING THE EXACT WEIGHT of the vehicle on which you are working, is important.

"Probably" is nearly as bad as outright guessing, and I take it that you already know my views on that?? !! :)
 

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@Turbo Ed Please do me a favor and have a look here. This is a CLA45s running under 500hp as the owner says. Are you saying the 70kg lighter A45s would need to have somewhere around 555 to trap just 3-4 mph higher? Honestly, comparing the two results, the Russian car don't look stripped to me. But it could be running just over 500hp.
Didn't you read what he posted earlier about calling anyone comparing acceleration times etc with GPS based measuring device without knowing the actual weight is being pointless and plain silly?

But for magical reasons the moment you're able to provide the weight of the car, all other variables becomes irrelevant. 🤣

I almost have to get someone to perform a brain exorcism on me to unload what I read had not at the end I realised I was wasting my time as he's also in the guessing game just like everyone else in their own way (though he's denying he isn't and still thinking the so called 50 years of experience was really a compliment rather than the other way around)
 

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Didn't you read what he posted earlier about calling anyone comparing acceleration times etc with GPS based measuring device without knowing the actual weight is pointless and plain silly?

But for magical reasons the moment you're able to provide the weight of the car, all other variables becomes irrelevant. 🤣

I almost have to get someone to perform a brain exorcism on me to unload what I read had not at the end I realised I was wasting my time as he's also in the guessing game just like everyone else in their way (though he's denying he isn't and still thinking the so called 50 years of experience was really a compliment rather than the other way around)
Putting words in my mouth.
We are only discussing 1/4 mile Trap Speeds here as related to Power and Vehicle Mass.
The majority of variables you wised to introduce ARE irrelevant, purely in that context and assuming we are talking about the same model vehicle each time, which we are .

As for ignoring you poor attempts at personal attack each time, well, I guess that is simply my preferred style.

Finally, I reiterate, don't guess, measure.
Starting with the real weight of your own vehicle.
 

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Putting words in my mouth.
We are only discussing 1/4 mile Trap Speeds here as related to Power and Vehicle Mass.
The majority of variables you wised to introduce ARE irrelevant, purely in that context and assuming we are talking about the same model vehicle each time, which we are .

As for ignoring you poor attempts at personal attack each time, well, I guess that is simply my preferred style.

Finally, I reiterate, don't guess, measure.
Starting with the real weight of your own vehicle.
Sure mate, whatever you say ;)

How is that considered an attack when you come in announcing your glorious years of experience but all that is seen here is like a scholar trying to ace that academic paper without any real life examples and being called out?

Just show us your car and what you've done with it (rather than what you are about to do to it) maybe?
 

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Sure mate, whatever you say ;)

How is that considered an attack when you come in announcing your glorious years of experience but all that is seen here is like a scholar trying to ace that academic paper without any real life examples and being called out?

Just show us your car and what you've done with it (rather than what you are about to do to it) maybe?
Happy to admit I have done NOTHING to it mechanically as yet and with the exception of the Posaidon box, will do nothing to it before Christmas, as I have posted on a number of occasions previously.
Partly because of our Lockdown; however far more the result of wanting to do a lot of data acquisition work, on the standard car, FIRST.
This is not news, I have made a number of references to this fact in the past.

However, while I am answering your latest pleasant post, I had better admit that by the end of this, I am going to need to offer you a partial apology.
The following list is, I think, as complete as you posted.
If I have missed a variable you would like addressed, I am sure you will bring it to my attention. :)

Remember, the notes are strictly in the context of the Russian example which we are discussing and their possible affect on the Trap Speed at the end of a 1/4 mile. NOTHING ELSE

Terrain:
I am not sure what you meant by this; however I believe the street surface in the video to clearly illustrate that there is no issue here.
Temperature: Yes, this will have some effect, granted and it would certainly have been nice if he had posted an ambient temp.
Air Density: Coming from where you do, I can see why this would of concern. However, in Moscow at night? No, no issue here.
Elevation: Ditto above.
Track conditions: Well they are pretty obvious here in the video as no issue. However, in addition, unless you are in the pouring rain or iced, generally speaking these do not ever have much effect on the Trap Speed.
Drag Coefficient: Again, in this particular case we are dealing with the same model vehicle, so no issue here..
However, let's say we were dealing with two different model vehicles, with different aero. In this case, there is no measurable effect on the Trap Speed at the end of the 1/4 Mile until the Trap Speed exceeds 150 MPH..
Driver behaviour. I think we would all agree that our car's launch control essentially eliminates this as an issue here. The Russians were most certainly using it ! :)
Timing Equipment: BANG!! This where you really have got me and for which I owe you an apology.
I have personally had very little to do with the "Dragy" equipment, being an old school conventional drag racer. and I really should have researched this better before originally answering you. As it transpires, for extremely good technical reasons, the Dragy, in this speed range of around 125 MPH, will show the quarter mile speed around 2 MPH faster than that which you would measure on the drag strip, old school and which is the basis for my formula calculations.

So, with the vehicle actually 1/4 mile drag strip trapping at 123 MPH, it obviously changes the calculations.
I apologise again for missing this variable.

Of course, ALL of the above are basically irrelevant, if you don't know the real mass of the vehicle being tested.
 

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Theo,
LOL!!
No, that is NOT what I said.

I said if the car weighs what mine does, IE 1640 KG, it would need 555HP to run 125 MPH in the quarter.
At the other end of the spectrum, if the Russian car was built on a stripper, as is available in Europe, (but not UK or Australia) and then they took out the rear seats and front passenger seat (which you would NOT be able to see in their video), it would probably end up around 1450 KG and only need around 485 HP to run 125 MPH in the quarter.

THEN I said, the truth is probably somewhere in the middle.

Which IS the most likely case.
It PROBABLY has around 500 HP, or a little more and weighs somewhere between 1500 and 1550 KG.
Yes, the Tune is set on "KILL" but hey, you know those crazy Russians!!!
One thing for sure, on their roads, (on which I have driven), no one is holding WOT for any serious length of time!! :)
Autobahns they are not!!

However, NONE of the above was the point I was trying to make.
I was trying to use this case as an example of why KNOWING THE EXACT WEIGHT of the vehicle on which you are working, is important.

"Probably" is nearly as bad as outright guessing, and I take it that you already know my views on that?? !! :)
But it is what you implied. You said at 1640kg (your car) it would be equivalent to 555hp. Then I showed you a CLA45s running under 500hp, weighs an extra 70kg and traps only 3-4mph lower than the Russians. How would you need this much power in a 70kg lighter car to cover a mere 3-4mph gap? In other words, I think your numbers are off.

As for the weights, although it's always a good thing to know, 99% of the time you don't. I challenge you to start a poll see how many owners have actually weighed their car. So what do you do if you don't know? You look at the average, yes you guess @Turbo Ed that's what you do and there's no shame in that. You can't measure everything, but I suppose after 50 years of experience in the turbo business I can understand precision has become second nature to you. You take the lightest spec vs heaviest spec (which is about 1580 to 1640 for the A45s and btw mine is probably about as heavy as yours, as I got it fully loaded) and take a wild guess, and your best bet is taking the average, which would be about 1610, maybe 1620 as most A45s's that I've seen are kinda loaded.

Now I would surely suspect the Russian car was stripped if it trapped let's say over 130mph and they claimed stock turbo. But as I said, for only 3-4mph above a CLA45s running under 500hp, there's no way that A45s is stripped. But if it was, I agree, it would require less power at 1450kg, in fact under 485 in my opinion (I believe 450 would be enough at that weight), but what if it was half-stripped, what if only the front passenger seat was removed, what if only the rears, what if the driver was 50kg, what if he was a behemoth that barely fit in the car and had to strap himself on the chassis? Power numbers would change every time. Fact of the matter is, guessing can go on indefinitely. Why don't we just save ourselves the trouble and take the average which is 1620kg and assume the A45s is not stripped and is running a bit over 500hp, which makes perfect sense!!
 
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Didn't you read what he posted earlier about calling anyone comparing acceleration times etc with GPS based measuring device without knowing the actual weight is being pointless and plain silly?

But for magical reasons the moment you're able to provide the weight of the car, all other variables becomes irrelevant. 🤣

I almost have to get someone to perform a brain exorcism on me to unload what I read had not at the end I realised I was wasting my time as he's also in the guessing game just like everyone else in their own way (though he's denying he isn't and still thinking the so called 50 years of experience was really a compliment rather than the other way around)
I think he just goes way to deep trying to analyze pretty much everything. It's like you want to hang a hammock between two trees, but it slips. What are you gonna do are you gonna get a sample, send it to the lab and have it analyzed to see what kind of hammock fits best? Or find a Y shaped stem and be done with it in two minutes.
 
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Happy to admit I have done NOTHING to it mechanically as yet and with the exception of the Posaidon box, will do nothing to it before Christmas, as I have posted on a number of occasions previously.
Partly because of our Lockdown; however far more the result of wanting to do a lot of data acquisition work, on the standard car, FIRST.
This is not news, I have made a number of references to this fact in the past.

However, while I am answering your latest pleasant post, I had better admit that by the end of this, I am going to need to offer you a partial apology.
The following list is, I think, as complete as you posted.
If I have missed a variable you would like addressed, I am sure you will bring it to my attention. :)

Remember, the notes are strictly in the context of the Russian example which we are discussing and their possible affect on the Trap Speed at the end of a 1/4 mile. NOTHING ELSE

Terrain:
I am not sure what you meant by this; however I believe the street surface in the video to clearly illustrate that there is no issue here.
Temperature: Yes, this will have some effect, granted and it would certainly have been nice if he had posted an ambient temp.
Air Density: Coming from where you do, I can see why this would of concern. However, in Moscow at night? No, no issue here.
Elevation: Ditto above.
Track conditions: Well they are pretty obvious here in the video as no issue. However, in addition, unless you are in the pouring rain or iced, generally speaking these do not ever have much effect on the Trap Speed.
Drag Coefficient: Again, in this particular case we are dealing with the same model vehicle, so no issue here..
However, let's say we were dealing with two different model vehicles, with different aero. In this case, there is no measurable effect on the Trap Speed at the end of the 1/4 Mile until the Trap Speed exceeds 150 MPH..
Driver behaviour. I think we would all agree that our car's launch control essentially eliminates this as an issue here. The Russians were most certainly using it ! :)
Timing Equipment: BANG!! This where you really have got me and for which I owe you an apology.
I have personally had very little to do with the "Dragy" equipment, being an old school conventional drag racer. and I really should have researched this better before originally answering you. As it transpires, for extremely good technical reasons, the Dragy, in this speed range of around 125 MPH, will show the quarter mile speed around 2 MPH faster than that which you would measure on the drag strip, old school and which is the basis for my formula calculations.

So, with the vehicle actually 1/4 mile drag strip trapping at 123 MPH, it obviously changes the calculations.
I apologise again for missing this variable.

Of course, ALL of the above are basically irrelevant, if you don't know the real mass of the vehicle being tested.
Nope, the notes is in the context of measuring acceleration with GPS based measuring device where the Russians were the conversation that led into this where you called everyone who is doing acceleration measurement without knowing their vehicle weight is being pointless and plain silly, and I called you out.

And measurement of acceleration includes 0-100, 100-200 and quarter mile as per the video shared by the Russians, not just solely focusing on quarter mile alone.

You're not getting it, I am agreeing with you that vehicle weight is important after you mentioned it. However, when you started making statements that the other variables aren't relevant just because that ONE sole vehicle weight is missing, I called you out again.

I am saying terrain, temperature, air density, elevation, track conditions, drag coefficient, driver behaviour, timing equipment are EQUALLY important as the vehicle weight. Some might even go the extreme to argue to even include tire pressure, tire temperature and humidity in order to be even more precise.

Well, in my opinion sure if all these information can be made available, that is great then because we can now better understand how the vehicle performed in those environment. However, in real life that isn't always the case is it?

So what is wrong with the people who uses a GPS based measurement device like VBOX, Dragy for example to measure and compare vehicle performance when they do not know the exact weight of their vehicle?

They're all being plain silly and pointless?

And really? Aero has no effect on the car's speed until it exceeds 150 MPH? Do you have any solid proof/data to back that claim? I am no expert myself but a simple research online would tell you a completely different figure and yours is way off.

And for arguments sake let's just say even it is the same vehicle, how do you know the Russian's A45S doesn't have any aero packs on them? But then you conveniently brought up the issue of the possibility of their vehicle being stripped down to have lesser weight?

Cherry picking much?

And PLEASE keep your backhanded apology to yourself when you're still harping on the fact that vehicle weight is the only thing that matters here. I know it is not easy for an aged person to admit their shortcomings, but that's okay.

Instead, I urge you to please back your claims with facts/real-life data to prove it, anyone with some self respect and dignity at this point would just walk the talk. Especially when you claimed you have over 50 years of experience.

And since you said that you're not going to do anything to your car until Christmas, then you really won't have any access to real life data would you? I mean that's perfectly fine if you want to continue a theory based approach in your analysis.

But then how can we all have large enough samples of data and turn this to a lab precision small deviation margin of error confidence then?

Well I say please carry on then, this is a free world after all and you may continue to post and share any opinions that you want. Of course, just that there would be people here to call you out, that's all.
 

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Which is precisely WHY I said to you on the other thread, if you have ever seen ANY real correlation between Engine Power as measured on either of the Aussie Dynos and a MSR500, it was simply a fluke, nothing more.
I guess it was a fluke that repeated itself, perfect.

Anyways f.. that, there's something else I want to ask you. Why on earth would you be interested in finding out if Maha is accurate? Are you some kind of dyno critic? It's like I'm about to buy a house but first I wanna see for myself if the architect is as good as people say he is, so I run background checks on his technique, rather than just walk around the house see if I like the darn thing and make it mine. Better yet, it's like I'm having a frigid cold Starbucks Frappuccino but before taking my first sip, I wanna see for myself if the blending machine is as good as they claim, so I ask for specs along with a full demonstration of the blending process. I've been trying to understand your way of thinking since your first post and to tell you the truth, you are one of a kind.
 

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But it is what you implied. You said at 1640kg (your car) it would be equivalent to 555hp. Then I showed you a CLA45s running under 500hp, weighs an extra 70kg and traps only 3-4mph lower than the Russians. How would you need this much power in a 70kg lighter car to cover a mere 3-4mph gap? In other words, I think your numbers are off.

As for the weights, although it's always a good thing to know, 99% of the time you don't. I challenge you to start a poll see how many owners have actually weighed their car. So what do you do if you don't know? You look at the average, yes you guess @Turbo Ed that's what you do and there's no shame in that. You can't measure everything, but I suppose after 50 years of experience in the turbo business I can understand precision has become second nature to you. You take the lightest spec vs heaviest spec (which is about 1580 to 1640 for the A45s and btw mine is probably about as heavy as yours, as I got it fully loaded) and take a wild guess, and your best bet is taking the average, which would be about 1610, maybe 1620 as most A45s's that I've seen are kinda loaded.

Now I would surely suspect the Russian car was stripped if it trapped let's say over 130mph and they claimed stock turbo. But as I said, for only 3-4mph above a CLA45s running under 500hp, there's no way that A45s is stripped. But if it was, I agree, it would require less power at 1450kg, in fact under 485 in my opinion (I believe 450 would be enough at that weight), but what if it was half-stripped, what if only the front passenger seat was removed, what if only the rears, what if the driver was 50kg, what if he was a behemoth that barely fit in the car and had to strap himself on the chassis? Power numbers would change every time. Fact of the matter is, guessing can go on indefinitely. Why don't we just save ourselves the trouble and take the average which is 1620kg and assume the A45s is not stripped and is running a bit over 500hp, which makes perfect sense!!
Theo,
I take it you "missed" my supposed backhand apology to our friendly Malaysian?
I cocked up the the Dragy Tech, through admitted lack of experience with it.

So 125 Dragy is actually close enough to 123 MPH in the quarter.

At the Min mass as published of 1550 KG 490 HP
At the Max mass as published of 1670 KG (no idea how you would get to that). 530HP

So, as you say, using an average mass, slightly over 500 HP looks likely and is hardly surprising in any way.
(Particularly as I know how the Russians tune!! :))

What IS so surprising to me is the apparent reluctance of any one here to obtain the the most basic and cheap data on their personal vehicle.
After HP itself, vehicle mass is unquestionably the next most important performance parameter.
****, I could have gone full Race Car and said Corner Mass and then obviously have everyone REALLY freak out.:)

Is it really so difficult (or expensive) to obtain actual total vehicle mass outside Australia?
When I did it shortly after starting to post here on the subject, even in the middle of a locked down city, I was out of the office for less than 30 minutes, most of which was driving the 10 minutes each way!
Cost me the equivalent of 15 PDs Sterling.
Tell me any other single piece of important data on your personal vehicle that you can obtain so easily and cheaply.
 

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Nope, the notes is in the context of measuring acceleration with GPS based measuring device where the Russians were the conversation that led into this where you called everyone who is doing acceleration measurement without knowing their vehicle weight is being pointless and plain silly, and I called you out.

And measurement of acceleration includes 0-100, 100-200 and quarter mile as per the video shared by the Russians, not just solely focusing on quarter mile alone.

You're not getting it, I am agreeing with you that vehicle weight is important after you mentioned it. However, when you started making statements that the other variables aren't relevant just because that ONE sole vehicle weight is missing, I called you out again.

I am saying terrain, temperature, air density, elevation, track conditions, drag coefficient, driver behaviour, timing equipment are EQUALLY important as the vehicle weight. Some might even go the extreme to argue to even include tire pressure, tire temperature and humidity in order to be even more precise.

Well, in my opinion sure if all these information can be made available, that is great then because we can now better understand how the vehicle performed in those environment. However, in real life that isn't always the case is it?

So what is wrong with the people who uses a GPS based measurement device like VBOX, Dragy for example to measure and compare vehicle performance when they do not know the exact weight of their vehicle?

They're all being plain silly and pointless?

And really? Aero has no effect on the car's speed until it exceeds 150 MPH? Do you have any solid proof/data to back that claim? I am no expert myself but a simple research online would tell you a completely different figure and yours is way off.

And for arguments sake let's just say even it is the same vehicle, how do you know the Russian's A45S doesn't have any aero packs on them? But then you conveniently brought up the issue of the possibility of their vehicle being stripped down to have lesser weight?

Cherry picking much?

And PLEASE keep your backhanded apology to yourself when you're still harping on the fact that vehicle weight is the only thing that matters here. I know it is not easy for an aged person to admit their shortcomings, but that's okay.

Instead, I urge you to please back your claims with facts/real-life data to prove it, anyone with some self respect and dignity at this point would just walk the talk. Especially when you claimed you have over 50 years of experience.

And since you said that you're not going to do anything to your car until Christmas, then you really won't have any access to real life data would you? I mean that's perfectly fine if you want to continue a theory based approach in your analysis.

But then how can we all have large enough samples of data and turn this to a lab precision small deviation margin of error confidence then?

Well I say please carry on then, this is a free world after all and you may continue to post and share any opinions that you want. Of course, just that there would be people here to call you out, that's all.
Apologies, again for not making it clearer.
When I said I wasn't doing anything on my car until Christmas, other than the POSAIDON box, I SHOULD have said any further mods.

Between now and Christmas, (and please keep in mind, we are going to be significantly locked down until well into October, at the earliest) , I intend to concentrate on comprehensive data acquisition of the standard engine, both on the dyno and in the real world.
This is simply because, before I start altering a seriously highly tuned stock engine, I want to know all about the approach taken with the original Engineering.
However, I freely admit, that's me. I like to have a fair idea of the implications of change, before I do them.
You can certainly put that down to an Aged Person's shortcomings, if you like.
.
Or, you could call it for what it REALLY is. A professional Engineering approach.

I am not going to comment further on the Russian post, simply because we are at cross purposes.
I took it as being posted to demonstrate the Power being obtained by the Russians.
ALL my comments regarding vehicle mass were in that context. alone.
You appear to have taken it in a much broader sense, which is you right, of course.
Just differently, so I shall leave it at that.

Sorry, you felt my apology was " backhanded" as it really wasn't.
I need to keep up with technology like the Dragy and should have checked the differences in how it functions as compared to traditional Drag Race timing, before I posted,
 
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