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2016 A45 FL | Stage 1 @ 430bhp / 475ft-lb
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Is that THE Shaun, of Subaru STI, to Mercedes W176 to Audi RS3 to BMW M4 fame?

Where do you find 200 KPH privately owned roads in a country a small as the UK?

Or is "private" a euphemism for airfields?

You are starting to give me second thoughts about all this.

Maybe i should just go for the Race Logic with the data logging Channel expansion boxes from the get go.
Didn't realise Shaun had a BMW M4? Where can I find his build?
Dragy is fine.
 

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One upmanship I clearly understand; however I would rather save it for things of more interest to me!! :)

Dragy it is!!

Now I just need to find an accessible 200 KPH test site, accessible at night, with the city in the middle of a 9.00 PM to 5.00 AM curfew!!
Only just catching with the jetlag from Spain :LOL:

I'd like to see how the excuse goes when the police stop you for breaking curfew. "Sorry officer I was lead astray by our colonial masters in the UK" 😂
 
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Is that THE Shaun, of Subaru STI, to Mercedes W176 to Audi RS3 to BMW M4 fame?

Where do you find 200 KPH privately owned roads in a country a small as the UK?

Or is "private" a euphemism for airfields?

You are starting to give me second thoughts about all this.

Maybe i should just go for the Race Logic with the data logging Channel expansion boxes from the get go.
It's not a one time attempt, unless you're jailed of course for breaking curfew. So just give it a spin and see what the numbers look like. We can chew the fat over the correction factors once we see what you get.
 
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While I occasionally do race other cars between stop lights and always late at night when traffic is very low, for my dragy runs I prefer the freeway, again late at night and when there's clear road ahead for my entire run and the nearest car behind me is like 300 feet away. 110mph is good for random street racing, but for dragy runs I wanna see what the car does to 150, which I believe isn't safe unless your on an empty freeway. I also use it if I'm racing a friend (or a family member 😂) and we wanna see what happens at higher speeds. Luckily the nearest freeway is only 5 minutes away from my place, but to get there in such a short time you have to take a toll road, otherwise it's a 20-25 minute drive, which of course is your only option after a cold start.

On a different note, is it possible that our cars have FWD losses after a certain speed? I'm saying that because it should be the only way I can be neck and neck with our 370hp and 500nm stage 1 Cupra which is FWD from 50 to 130mph. The Cupra weighs in at about 1420kg and that means we have the same crank power to weight, so our result makes perfect sense. Of course above 130mph I do creep away and that's down to gearing and bigger turbo but up to 130 there is absolutely nothing in it. How could that be possible if I'm having AWD losses? I need someone to explain that to me.
 

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Yup, A35 and A45 & A45s are not full time permanent AWD systems.
But it won't revert to pure FWD losses, as it's still driving the rear prop shaft and input to the rear diff clutches at all times.
 

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While I occasionally do race other cars between stop lights and always late at night when traffic is very low, for my dragy runs I prefer the freeway, again late at night and when there's clear road ahead for my entire run and the nearest car behind me is like 300 feet away. 110mph is good for random street racing, but for dragy runs I wanna see what the car does to 150, which I believe isn't safe unless your on an empty freeway. I also use it if I'm racing a friend (or a family member 😂) and we wanna see what happens at higher speeds. Luckily the nearest freeway is only 5 minutes away from my place, but to get there in such a short time you have to take a toll road, otherwise it's a 20-25 minute drive, which of course is your only option after a cold start.

On a different note, is it possible that our cars have FWD losses after a certain speed? I'm saying that because it should be the only way I can be neck and neck with our 370hp and 500nm stage 1 Cupra which is FWD from 50 to 130mph. The Cupra weighs in at about 1420kg and that means we have the same crank power to weight, so our result makes perfect sense. Of course above 130mph I do creep away and that's down to gearing and bigger turbo but up to 130 there is absolutely nothing in it. How could that be possible if I'm having AWD losses? I need someone to explain that to me.
I think the AWD drive losses will be higher in the A45s where we have the rear drive gears as standard. I'm guessing that's why we get the + added to our 4matic as well.

With some of the numbers people are getting where the engine is producing well over 421 bhp and 369 lbs ft it will be interesting to see @Turbo Ed pre and post numbers. And with Australia still in its cooler months we should hopefully get some good numbers.
 
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Maybe our losses is somewhere in between then, but perhaps closer to the approximate FWD number which is 12-13%. Maybe it's 16% or something and at the same time my car actually makes 435 crank which is possible from what I've seen here. In that case, If you put down the numbers, the Cupra still has wheel power to weight advantage but I suppose it's small enough for our gearing and bigger turbo to compensate. It just wouldn't make sense if I had the full 24% losses, so thanks @veeeight for clarifying that.
 

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2021 AMG A45 S Plus, Sun Yellow, DTUK 470 PS, Akrapovic Evolution in Ti
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Maybe our losses is somewhere in between then, but perhaps closer to the approximate FWD number which is 12-13%. Maybe it's 16% or something and at the same time my car actually makes 435 crank which is possible from what I've seen here. In that case, If you put down the numbers, the Cupra still has wheel power to weight advantage but I suppose it's small enough for our gearing and bigger turbo to compensate. It just wouldn't make sense if I had the full 24% losses, so thanks @veeeight for clarifying that.
The Maha measured my stock WHP at 369.2 and calculated Crank HP at 437.7 so a loss of 15.65%
 

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The Maha measured my stock WHP at 369.2 and calculated Crank HP at 437.7 so a loss of 15.65%
We'll probably get an update from a jail cell from @Turbo Ed overnight of what he achieves.
 

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Yup, until this day seems like everyone has their own way of calculating drivetrain losses (me included).

Because I did the dyno measurements of my previous Golf R and the W176 A45 on the same exact dyno for the current CLA so I just used the same differences of the manufacturer claimed output vs measured power at the wheels as the drivetrain losses ratio solely for my own references.
The problem with this approach when applied in a Macro, worldwide, sense, (as opposed to your personal "micro" situation) is the genuinely massive differences in power levels as measured at the tyres by the various brands of Dynos. ( let alone the differences between two dynos of exactly the same make and model, installed in two different countries)

Which is precisely the reason that doing what you do, is the ONLY way to use a dyno.
Precisely as you say, always use the exact same dyno and simply use the numbers as a reflection of before/ after change.
NOT as an absolute number.

Now, of course, the Dyno which supposedly eliminates all the preceding is the Maha MSR500.
Obviously Litchfield believes it does, reinforcing their original 2014 decision by presumably spending significantly more money to update to the latest spec sometime in the last couple of years.
I see an increasing number of UK Tuning shops also adopting the MSR500, so there is obviously something there.
I don't believe there is a reputable Tuner in Germany NOT using the MSR500 these days.

I just wish I could get my car onto to the only one in my city.
I haven't given up yet though! :)

Internationally though, the most confusing Chassis dyno in widespread use, particularly in the States; however, in various other locations around the world, is the DynoJet..
There is literally NO method of comparing DynoJjet numbers with any other chassis dyno, let alone engine power numbers, as it works on an entirely different method of measurement

IE It is an inertia measurement device, as opposed to the the more normal load measurement device.

The reason for the difference?
COST, nothing else.
The DynoJet is literally a fraction of the cost of a real load measurement chassis dyno.

.
 

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The problem with this approach when applied in a Macro, worldwide, sense, (as opposed to your personal "micro" situation) is the genuinely massive differences in power levels as measured at the tyres by the various brands of Dynos. ( let alone the differences between two dynos of exactly the same make and model, installed in two different countries)

Which is precisely the reason that doing what you do, is the ONLY way to use a dyno.
Precisely as you say, always use the exact same dyno and simply use the numbers as a reflection of before/ after change.
NOT as an absolute number.

Now, of course, the Dyno which supposedly eliminates all the preceding is the Maha MSR500.
Obviously Litchfield believes it does, reinforcing their original 2014 decision by presumably spending significantly more money to update to the latest spec sometime in the last couple of years.
I see an increasing number of UK Tuning shops also adopting the MSR500, so there is obviously something there.
I don't believe there is a reputable Tuner in Germany NOT using the MSR500 these days.

I just wish I could get my car onto to the only one in my city.
I haven't given up yet though! :)

Internationally though, the most confusing Chassis dyno in widespread use, particularly in the States; however, in various other locations around the world, is the DynoJet..
There is literally NO method of comparing DynoJjet numbers with any other chassis dyno, let alone engine power numbers, as it works on an entirely different method of measurement

IE It is an inertia measurement device, as opposed to the the more normal load measurement device.

The reason for the difference?
COST, nothing else.
The DynoJet is literally a fraction of the cost of a real load measurement chassis dyno.

.
The MSR500 is not held in high regard without reasons.

I myself am not a fan of inertia dyno at all like the Dynojet, I always joke about it and call it the "happy" dyno.

I mean yeah the operators claim their model has additional eddy current brakes (some of them calls it retarders) to simulate load yada yada, but still an inertia dyno is an inertia dyno regardless how they put it.

And unfortunately for unknown reasons (maybe really due to the much cheaper price) that is the only brand that all the operators here are using within my area so I had to make due with whatever that is available. In a way, it is kind of depressing actually when come to think of it.

At the end, I am just treating it as a tool to measure the before/after numbers regardless of the accuracy (because we know it is all happy numbers on the Dynojet) and yes if anyone tries to argue that the numbers the Dynojet puts out is absolute will absolutely get an earful from me. 😁
 

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The MSR500 is not held in high regard without reasons.

I myself am not a fan of inertia dyno at all like the Dynojet, I always joke about it and call it the "happy" dyno.

I mean yeah the operators claim their model has additional eddy current brakes (some of them calls it retarders) to simulate load yada yada, but still an inertia dyno is an inertia dyno regardless how they put it.

And unfortunately for unknown reasons (maybe really due to the much cheaper price) that is the only brand that all the operators here are using within my area so I had to make due with whatever that is available. In a way, it is kind of depressing actually when come to think of it.

At the end, I am just treating it as a tool to measure the before/after numbers regardless of the accuracy (because we know it is all happy numbers on the Dynojet) and yes if anyone tries to argue that the numbers the Dynojet puts out is absolute will absolutely get an earful from me. 😁
The "happy" dyno? :) Cute!! :)
Around here they are know as the "Drum of Concrete" dyno, although I believe there are are only a couple in the entire country.

You are 100% correct in both your comments.
a) Only ever use it as a before/ after tool, although as you will see in another post, that applies equally to ALL chassis dynos, even of the same brand/ model.

b) Workshops, even in their home country of the States, only ever purchase a DynoJet for one reason, COST.
I can give your some home country costs, for AWD performance models which although a few years out of date, still illustrate the relativity.
I have made them all Pounds Sterling, in deference to the Colonial Masters.
All prices starting costs, in their home country without options. (Maha's options can add 50% to their price!!)
Maha 100,000 Pounds..
Superflow 80,000 Pounds
DD or Mainline 80,000 Pounds ( they both offer "lightweight", cheaper models; however, I am trying to keep the comparison valid to the Maha)
Mustang 60,000 Pounds
DynoJet 40,000 Pounds

Of course, this is prior to any sort of Customs Duties or VAT which may apply in any final use country.
 

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Another book coming in...
Apologies in advance!!! :)

I'll. TRY to keep it as simple as possible.

There are two entirely separate questions here

1) The variation in measurement of power at the tires..
No two dynos, even of the same brand and model, will give exactly the same results.
Which is why it is essential that you use exactly the same dyno every time you make changes you want to quantify.
Why, you ask, do they all give different numbers?
The full explanation WOULD take the book to which Forrester refers :)
So, I'll just give you arguably the single biggest reason.
Control of ambient test conditions.
Those of you that are interested in this subject, please go to Litchfield's website, or better still go to their facility and look at their Test Cell.
It looks pretty good, although I designed and commissioned a better one around fifteen year's prior to theirs's being built.
Why was ours better? Simply because it was designed to keep test conditions within a an acceptable range, (20 to 25C) in 45 degree ambient.
IE we needed to be able to continue development during a normal Australian summer.
I suspect Litchfield's would be all done on a 30C day; however given the country in which they work, I am sure that is fine.
Just ONE of a number of performance elements arising from this situation.
Intercooler performance.
If you think it doesn't matter whether the ambient air cooling the intercooler is at 20C or 45C, then you really need to do some reading.
A good dyno will have compensation for the temperature of the air entering the engine's air cleaner, however it has absolutely no method of compensating for variations in Intercooler performance..
This is just ONE example of why controlling the test conditions within the Cell is crucial to repeatability. (The Holy Grail of any development engineer)
There are a number of other issues in a similar vein.
So, what is the big deal about all this?
As always, COST!
I don't know what Litchfield spent on their cell in 2014, however, in 1999, I signed off on invoices exceeding the equivalent of 100,000 Pounds, THEN.
( Yes, more than the Dyno, itself)
More to the point, it was no where near OEM standards.

You will read where Maha quite rightly states that many of the German OEM's use their MSR500.
What they DON"T tell you is that the Test Cell in which it is located, probably cost AT LEAST five times the cost of the Dyno itself!!!
Who in the aftermarket is going to spend this sort of money?
The answer is obvious, no one.
So the best you can do as a performance enthusiast is always use the same chassis dyno, note the ambient conditions on the day and only ever treat the numbers as relative change, not as absolute figures.. ( Given that whatever the test condition issues, they are at least much the same for any given dyno install)
NEVER compare the tire power numbers from one chassis dyno to another.
The exception to the above rule, being, in theory, the Maha MSR500, in a correctly designed Test Cell and not using the tire power numbers it shows, but its extrapolated engine power numbers.

2) Which neatly bring us to the question of extrapolating engine power numbers from a figure measured at the tires.

Let's leave Torque converters and slipping clutch plates out of the equation, for simplicity sake.
Where are there drivetrain losses in modern passenger vehicle?
1) Clutch? No (Assuming it is not slipping).
2) Gearbox? No ( Any good dyno operator runs in direct, the equivalent of 1:1)
3) Hypoid gears? A very small figure (where the power change direction)
4) The tires? Think this is strange? I have personally seen over 50 HP alteration on the same vehicle simply by changing tires.
This being ANOTHER one of the variations to which I was referring in the tire power comparison above.
Note to self. Always test with the exactly the same tires.
Just as you have winter and summer tires, if you are serious you should have a set of Dyno wheels/tires.
As some of you already know, I have a set of 255 Continentals on 9s on my vehicle.
I keep the OEM 245 Michelins on the 8.5's for Dyno work.

So, WHICH of the above power train items should change, if one increases the engine power being transmitted thorough them to the tires to the rollers?
The answer is one or two HP through the hypoid gears and Maha claims they can even measure this using their coast down method.
Basically, there IS no substantial change in drive train losses, as the engine power increases.
Or whatever they are, are within the range of normal experimental error and therefore irrelevant.
Given typical aftermarket high performance Test Cells, there will be a lot more variation due the ambient condition change within the cell, than from increased drivetrain loss.

An example?
Let's take our vehicle in standard specification on a Maha
Unless you have a " hottie" like @nn7man's, around 350 at the tires, 70 HP drivetrain loss total 420 HP
Install a hybrid turbo and supporting mods, tune, and increase the tire HP to 450 HP, the Maha will show correctly 520 at the engine, NOT 535 HP, (which is what a DD or Mainline Dyno, for example would incorrectly show)

THIS is why Litchfield, and an increasing number of discerning Tuners around the world have bought/ are buying Maha MSR500's.

If you cannot get onto one, and I for one am having serious problems in doing so, get onto a quality tire measurement dyno, stick to always using the same one and only ever talk about what your car's power changes are at the tires, as you make your mods.

Sorry, Forrester, et al,
I DID try!! :)
 
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