Liquid S3 Readings!!

[S£]

Right guys i need some help, took the car out for a spin to check things over and noticed my Maf reading was 180 g/s max... BHP 233 max and 283 torque, by this i would say that the maf is ******** thats why my BHP is down, but i did some research and I'm lead to believe that a maf reading of 180g/s is right for a S3 with 225bhp but not a mapped S3 like mine.. it should be 205g/s ish...but why isn't my torque down as well or wouldn't it be?? or is my car not down on power the maf reading & BHP do add up right, and it's the crap map it's self, i don't know who done the map, all i and the previous owner know was it was done from new, so 7 years old, but why is my torque how a mapped S3 should be... with a loss of 25bhp Grrrrrrrhhhh

maybe the same monster that stole kiteyboy's horses stole mine too!!

Also does anyone know what my air/fuel ratio should be and also what my lamba reading should be?

Thanks if anyone can help me!!

 

[s3ollie]

i belive the correct (perfect) AF ratio is 12.5/1

 

[s3ollie]

the optimun lambda reading (stoichiometric point) should be 0.45v

 

[s3ollie]

re the torque: are you sure its not calculating in NM's? coz 280 NM is stock

 

[freegeek]

Best thing to do is to create a dyno plot and then post up a picture of it. But your maf may or may not be faulty,

I high torque reading means that you are getting good bhp at low revs which is what you want. However the chances are it is a very short spike.

The peak torque you are reading is almost certainly due to a spike in the boost pressure beyond what your map is asking for, my tt does this too. If you plot the actual and requested boost you will be able to see this spike. If the overshoot is big you will also get a big torque spike.

But your max bhp dooes look on the low side, I would be looking for at least 255/260 from a mapped 225 car, or a maf of at least 210g/s. Did you take it all the way to the red line, you probably will hit max bhp at 6.5k revs

So it could be an odd map or a dodgy maf.

Hers is my dyno,

 

[freegeek]

Also, does your S3 have a narrow band or wide band lambda sensor. The liquid is set up for a wide band at the moment, I'll add narrow band support sometime later.

 

[freegeek]

Also you will find that no two runs will be identical, and unless you do a bit of gentle cruising between runs, heat soak will set in and impact your readings, so do a few runs to build up a feeling for what you can achieve.

Have you decided what you are going o do for a mount yet?

 

[freegeek]

Finally, did you have any faul codes?

 

[themanthatcan]

Also, does your S3 have a narrow band or wide band lambda sensor. The liquid is set up for a wide band at the moment, I'll add narrow band support sometime later.

I think that's quite key information that maybe people should have known about earlier. The BAM engine (225) is the only one on the S3 to have a wideband O2 I believe, so what are those people running narrow-bands actually missing out on?

 

[freegeek]

"What are they missing out on?"

Well the AFR display, it does not impact any other displays, but it is easy to rectify.

If someone can post up a vag-com log of the narrow band sensor for a WOT it would help with the modificaion to the software.

Once I make the change I'll put the selection of narrow band/wide band ino the setup menu and have it as a preset default.

FYI software upgrades are provided free of charge (plus small postage handling charge).

I have already sarted on this feature and was using the info from here

http://www.supracentral.com/index.php?option=com_content&task=view&id=77&Itemid=42

 

[scott_johnson]

pics of any mounts on the s3??

 

[S£]

my engine is the 210 amk so i presume then i have narrow band lambda then, i'll have a look at the readings on that tomorrow, also i didn't really have a play with the dyno, i presume it's a standing start in 1st then to the red line to get the reading?? I'll check for a fault code tomorrow aswell.

Jim i'm going to mount it in the vent, nev has mine at the mo so hopefully i'll have some pics up next week!

 

[themanthatcan]

my engine is the 210 amk so i presume then i have narrow band lambda then, i'll have a look at the readings on that tomorrow, also i didn't really have a play with the dyno, i presume it's a standing start in 1st then to the red line to get the reading?? I'll check for a fault code tomorrow aswell.

Jim i'm going to mount it in the vent, nev has mine at the mo so hopefully i'll have some pics up next week!

Yep the AMK is narrow-band. Well that's what JKM told me anyway.

Power runs are generally done in 3rd or 4th gear from around 2k RPM to the redline. Obviousky you'll need to find a suitable private road as you can be hitting 80 in 3rd gear near the redline.

 

[freegeek]

3rd gear is best as you get a good amount of data points, 1 and second are over too quick and 4th and above are too fast.

 

[S£]

ah ok i'll try the dyno tonight and see what i get. As for fault codes no didn't have any other than a break light one. My lambda reading thismorning was 0.950ish to around 1.100ish then when i let off the accel to free run, it quickly spiked to 1.990 off the scale, then back to .950 so i wouldn't know what to make of that but i presume it's wrong as i have the narrowband.

Also jim, how accurate are the bhp and torque readings? Are they better than having a rolling road done?

Anyway so far i'm really happy with it and the fact that jim can update it and add suff is handy too as I'm sure when this becomes more popular people will be coming up with new requests for readings etc..

Top work Jim!

 

[themanthatcan]

Also jim, how accurate are the bhp and torque readings? Are they better than having a rolling road done?

These sort of devices can only ever be taken as a rough guesstimate when it comes to power readings. The figures are all based on calculations performed on certain readings taken from sensors on the car. If you want a proper "accurate" power reading then you need to get the car on a dyno.

 

[S£]

These sort of devices can only ever be taken as a rough guesstimate when it comes to power readings. The figures are all based on calculations performed on certain readings taken from sensors on the car. If you want a proper "accurate" power reading then you need to get the car on a dyno.

But people always go on about how unreliable figures are on a dyno on this forum, so surly the differance can't be much, a rough idea is good enough for me!

 

[freegeek]

ah ok i'll try the dyno tonight and see what i get. As for fault codes no didn't have any other than a break light one. My lambda reading thismorning was 0.950ish to around 1.100ish then when i let off the accel to free run, it quickly spiked to 1.990 off the scale, then back to .950 so i wouldn't know what to make of that but i presume it's wrong as i have the narrowband.

Also jim, how accurate are the bhp and torque readings? Are they better than having a rolling road done?

Top work Jim!

My lambda typically looks like this http://racediagnostics.com/images/lambda.wmv , let me know how this compares to yours.

Any time that your engine goes into over run, the ecu cuts the fuel to the engine to improve mpg so you will see the the lambda flick up to the max value.

As for the accuracy, I calculate BHP = MAF/0.8, now you can argue till the cows come home about this but globally this is acceped as the best approximation.

Ther was a long thread about this on the TT-forum, i'll try to dig it out and post a link.

As for the accuracy of rolling roads, I would be willing to bet that you will never get the same results twice from any car on two RR set ups. All car forums are full of arguments over this.

With the liquidS3 at least comparisons between "before and after mods" and between cars is going to be a better comparison. And you get instant results.

 

[S£]

Jim, I've done a couple of runs, what do you think!!!? a bit all over the place! The first one, i think i didn't start right, seems to climb way too quickly.. The maf was still showing 180g/s today, i also went out in my friends S3 too, mapped to 265 by Jabba, with a new maf on, he was hitting 195 g/s and similar bhp & ftlb but he does have a knock sensor code up which keeps reappearing, so he was low on power too.

On the way home i did get fault code 16487 come up...MAF?!?!?
but these runs were before the code came up. http://wiki.ross-tech.com/index.php/16487/P0103/000259

 

[Essflee]

Just like to know...these calculations that are used to work out the power output, are they based at the fly wheel or at the wheels ??

Also the TT that was tested, what was the boost pressure for the Turbo, mine and S£ were very similar and peaked at 1.550 bar / 23psi.....

 

[freegeek]

To get a good plot, get into 3rd gear on a flat section of road with the revs at 1500rpm, the car should be happy to chug along at this speed, next select the dyno plot and wait a couple of seconds at the same speed. As soon as the liquid syncs up with the engine management ECU (about 2 seconds) values will apear in the results box, then floor it to the redline. It looks like you went a bit early in the plots above.

As for the max bhp numbers they do look low but your getting a great mid range 3k boost which matches up with the best runs on my TT. Normally my tt will max out at mid 270 to 280ftlb but will occationally give me a 290+ spike.

You will be able to see the cause of this if you do a few plots of the boost pressure and command pressure on the same chart, occationally you will see the actual boost take a blip much higher than the commanded value.

As for your trouble code, it could be intermittant so clear it down and watch out for it appearing again.

Here is an example of the over boost spike, not a great example but you will se it spike much higher from time to time. The area is actual boost and the while line is the command (requested) boost.

This is a dyno run i did tonight with an example of an unusually high torque figure.

Ohh and last here is a video of me playing with the secret super hidden feature here.

 

[freegeek]

Just like to know...these calculations that are used to work out the power output, are they based at the fly wheel or at the wheels ??

Also the TT that was tested, what was the boost pressure for the Turbo, mine and S£ were very similar and peaked at 1.550 bar / 23psi.....

All the numbers are at the flyweel.

My TT peaks at about 1.45 so is not making as much mid range power as yours, yours is also spooling up fater than mine by about 200rpm, always interesting to see what bhp you are getting at 3k rpm.

However it seems that mine is holding a higher boos than yours at the higher revs.

Having this tool is great for comparing various maps and chosing what you are looking for.

Eventally we should have a good database of all the remaps out there.

 

[S£]

To get a good plot, get into 3rd gear on a flat section of road with the revs at 1500rpm, the car should be happy to chug along at this speed, next select the dyno plot and wait a couple of seconds at the same speed. As soon as the liquid syncs up with the engine management ECU (about 2 seconds) values will apear in the results box, then floor it to the redline. It looks like you went a bit early in the plots above.

As for the max bhp numbers they do look low but your getting a great mid range 3k boost which matches up with the best runs on my TT. Normally my tt will max out at mid 270 to 280ftlb but will occationally give me a 290+ spike.

You will be able to see the cause of this if you do a few plots of the boost pressure and command pressure on the same chart, occationally you will see the actual boost take a blip much higher than the commanded value.

As for your trouble code, it could be intermittant so clear it down and watch out for it appearing again.

Here is an example of the over boost spike, not a great example but you will se it spike much higher from time to time. The area is actual boost and the while line is the command (requested) boost.

This is a dyno run i did tonight with an example of an unusually high torque figure.

Ohh and last here is a video of me playing with the secret super hidden feature here.

Ahh so command pressure is what the ecu is asking for and you can compare against actual in the graph menu can you?? i thought you could only have boost or requested boost? how can i get both up, not played with it to much to find that out yet!

and yeah i think it will be really good when a few get this and we can all compare, different maps,mods, etc... It will be interesting to find out!

I did check the lambda, mine is the same as yours so i presume i have the wideband one too, Leggys reacted the same too. so i presume all is ok in that department!!

As for the Maf code it does come up every so often i normally clear it and it comes back with in a few days, so i presume its an intermittent fault otherwise it will come back straight away, i might just buy a new one and see where i get to, see if my readings will get above 200g, then if it doesn't at least i know my car is probably running ok and is just the map itself

I'm interested in how much difference a FMIC will make to the intake temp, i think putting a custom one together over the winter will be in order!

I can see a long battle with me and this little computer to achieve the best readings i can!!

 

[freegeek]

You can do it either way around, once you are in the boost graph display, push the joystick up, it may take a couple of trys because of the micro concentrating on the communications. This will put the secondary display on. To freeze the screen, push the joystick to the right.

PS its all in the user manual.

As for the FMIC, you won't improve your best figures but you will be able to maintain it when driving hard.

 

[freegeek]

How accurate is the 0.8 calculation -

There was a long thread about this on the TT-forum, i'll try to dig it out and post a link.

OK I found the link with the 0.8 discussion, here is the conclusion,

An oft quoted figure is BHP = MAF/0.8 for the standard VAG inlet barrel/MAF and Bosch Motronic 7.1 injection system used on nearly all VAG 20V1.8 NA & T engines

This is very approximate and is an empirical fugure derived from many rolling road sessions. It represents, crudely, power at the flywheel and is backed up (approximately) as follows:

MAF @ 210g/s = 16.8g/s fuel at 12.5:1 ratio (WOT) = 23cc/s fuel

1cc/sec fuel = ~45HP @ 100% efficiency

23cc/sec fuel @ 25% efficiency (best case at optimum running point)
= ~260BHP = ~MAF reading/.8

The full thread is here but it is is 11 pages long, the above is on page 8. http://www.tt-forum.co.uk/forum/viewtopic.php?f=2&t=113502&p=1215611#p1215611

 

[Essflee]

Freegeek.....the graphs that have been put up on this thread were all S£'s... i know my outputs were very similar but i dont know about the graphs. When we took my car out i was struggling to get over 185 on the maf reading, do think that would be down to the weather or do think it could do with a clean ? I know i have a knock sensor issue which the car is going in for soon, perhaps that is causing the poor bhp figures....S£ said that apparently the maf reading on a remapped S3 should be about 205-210ish....

 

[freegeek]

Its difficult to say, but 185 is really low for a remapped car, could need a clean, but that has its own dangers.

A good how to is here http://www.wak-tt.com/mafclean/mafclean.htm