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Dragy for me too, preferably 100-200 kmh
Copy that, thanks for the advice.
The Dragy certainly appears to be a fraction the price of the Race Logic product.
Given they are both UK products, what do you locals think of their relative value?

With respect to the Dragy product, are there any model variations and is one superior in performance to another?
 

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The race logic product was first in market many years ago, and had steadily been updated throughout the years to its current iteration. It is the closest in accuracy, but expensive.

Dragy and Racebox are very much newer entrants to the market, but they all use the same GPS Doppler frequency shift technology, it all comes down to the individual calibration/configuration of the units themselves, but even with Dragy or Racebox, you're never going to be further than 0.2s adrift from absolute values, and even then, only in certain measurements.

Value for money wise, it's very difficult to justify an additional £300 for that last 0.2s, especially as there are so many other factors that will give you a larger variance than that ;)

With all these systems, the more satellites you let it acquire, the higher the accuracy and resolution.
 

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I have Dragy too. If used with phone camera the times are shown on top of video 👍
 

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OK guys, so what do I get that you will all accept as comparable to what you are doing yourselves?

Makes little or no difference to me, just want to be able to provide uncontested data,
Dragy.
 

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The race logic product was first in market many years ago, and had steadily been updated throughout the years to its current iteration. It is the closest in accuracy, but expensive.

Dragy and Racebox are very much newer entrants to the market, but they all use the same GPS Doppler frequency shift technology, it all comes down to the individual calibration/configuration of the units themselves, but even with Dragy or Racebox, you're never going to be further than 0.2s adrift from absolute values, and even then, only in certain measurements.

Value for money wise, it's very difficult to justify an additional £300 for that last 0.2s, especially as there are so many other factors that will give you a larger variance than that ;)

With all these systems, the more satellites you let it acquire, the higher the accuracy and resolution.
Cutting through all that I'm hearing Dragy. So fairly unanimous.
 

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One upmanship as one would expect from Shaun.
 

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Before any of us get too excited, can anyone here tell us from what Dyno these figures are originating?

I can see the control software they are using, (SuperFlow WynDyn) which is American in origin.

I have looked at their website and am not sure as to the. Make of the dyno bed, although I believe it probably also a SuperFlow.

However, the REAL question is; how they are getting from the Tyre power number they are obviously measuring, to the Engine Power number in the graph.?

I have emailed them with this question and if they respond, will obviously post it.
 

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One upmanship as one would expect from Shaun.
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!!
 

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Before any of us get too excited, can anyone here tell us from what Dyno these figures are originating?

I can see the control software they are using, (SuperFlow WynDyn) which is American in origin.

I have looked at their website and am not sure as to the. Make of the dyno bed, although I believe it probably also a SuperFlow.

However, the REAL question is; how they are getting from the Tyre power number they are obviously measuring, to the Engine Power number in the graph.?

I have emailed them with this question and if they respond, will obviously post it.

I have looked at SuperFlow's site.
They claim they basically undertake the same process as the Maha to obtain Flywheel numbers; however apparently just don't show it on screen.
If they do and it is done well, then I guess those numbers are probably close to a Maha's.
The Italians obviously getting close to the Russians!! :)
 

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I've tested my Dragy against a friend's VBOX Performance Box Touch and the difference is between 0.01 - 0.02 seconds, I think the times are close to each other mainly due to both using the same sampling frequency at 10hz.

The higher range of VBOX equipment is able to log at higher frequency up to 100hz but I am not able to lay my hands on it to test the differences at the moment.

In my opinion mainly the slope correction feature is one of the reasons many would prefer over the traditional measuring devices despite the higher logging frequency.
 

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I've tested my Dragy against a friend's VBOX Performance Box Touch and the difference is between 0.01 - 0.02 seconds, I think the times are close to each other mainly due to both using the same sampling frequency at 10hz.

The higher range of VBOX equipment is able to log at higher frequency up to 100hz but I am not able to lay my hands on it to test the differences at the moment.

In my opinion mainly the slope correction feature is one of the reasons many would prefer over the traditional measuring devices despite the higher logging frequency.
Since you have obviously has significant experience with the Race Logic product, do you believe it is worth the difference in price?

In Australia, as close as possible to like for like models, it is almost four times the price of the Dragy unit,
 

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Since you have obviously has significant experience with the Race Logic product, do you believe it is worth the difference in price?

In Australia, as close as possible to like for like models, it is almost four times the price of the Dragy unit,
It really depends on the model you're looking at @Turbo Ed but if you're referring to VBOX Performance Touch I really can't seem to justify spending the extra now that I know they're both similar in terms of measurement.

Perhaps may I suggest you go with Dragy first while over here I'm trying to locate a Racelogic product with a higher sampling frequency and test it out to see whether it is worth the extra amount.

I'm also trying to determine whether the higher models actually has slope correction feature built in.

On the side note, I am also going to get my car's weight measured after I have collected it from Mercedes Malaysia as I sent it in for a minor paint job.

In that way not only we can have measurements from Dragy and but also with the car's weight included. :)
 

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It really depends on the model you're looking at @Turbo Ed but if you're referring to VBOX Performance Touch I really can't seem to justify spending the extra now that I know they're both similar in terms of measurement.

Perhaps may I suggest you go with Dragy first while over here I'm trying to locate a Racelogic product with a higher sampling frequency and test it out to see whether it is worth the extra amount.

I'm also trying to determine whether the higher models actually has slope correction feature built in.

On the side note, I am also going to get my car's weight measured after I have collected it from Mercedes Malaysia as I sent it in for a minor paint job.

In that way not only we can have measurements from Dragy and but also with the car's weight included. :)
OK Dragy it is.
They are so cheap it really doesn't matter if I have to throw it away after you have completed your investigations.

One of the things which appears nice about the more expensive Race Logic products is the ability to link my engine data logging directly into it.
Which, cost aside I must admit, would be useful.


My biggest problem right now is a test location in the middle of a seriously enforced 9 PM to 5 AM Curfew
 

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When Shaun used to get figures from his pBox, he was very insistent on not only using vbox verify, but also a separate verification program to take into account the slope factor.

The front page of vbox verify has a sample chart from a 100Hz device:
(Ignore the “calculate your car horsepower”) !!!!

In addition to all this - whenever I do runs, I always choose a strip of (private) road where I can do the run in both directions, and then take the average of the two figures from both directions.

in addition to running it through the verification program.
 

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When Shaun used to get figures from his pBox, he was very insistent on not only using vbox verify, but also a separate verification program to take into account the slope factor.

The front page of vbox verify has a sample chart from a 100Hz device:
vBox Verify
(Ignore the “calculate your car horsepower”) !!!!

In addition to all this - whenever I do runs, I always choose a strip of (private) road where I can do the run in both directions, and then take the average of the two figures from both directions.

in addition to running it through the verification program.
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.
 

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However, the REAL question is; how they are getting from the Tyre power number they are obviously measuring, to the Engine Power number in the graph.?
This is always the bit that fills me with dread, especially if/when plucking a number of of thin air for drivetrain losses, which will be greater for AWD!
 

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Maybe i should just go for the Race Logic with the data logging Channel expansion boxes from the get go.
Go for the Dragy to start. They really are that cheap it’s always useful to have around anyway, even if you decide to have a Racelogic setup later.
 

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This is always the bit that fills me with dread, especially if/when plucking a number of of thin air for drivetrain losses, which will be greater for AWD!
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.
 
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