View Full Version : Who needs a rolling road!
Steve3961
03-01-2002, 18:52
Reading someone else's comments (i think Bills) about being able to check you engines torque through 1551 (and i think VAGCOM) I decided to try it at work today. And guess what......
It works!
In measuring value 120 you can check your engines torque at what rpm so with the correct equation you can work out BHP!
Very handy!
Tried on a 1.8T Audi A6, The display said 220NM of torque and the book said it should have 210NM (Had done 70000miles) hence the higher figure.
Bill, I think this will be particully usefull to you to check for your lack of power without expensive rolling road time.
And is a easy way to check power output!
ibizacupra
03-01-2002, 20:34
Originally posted by Steve3961
Reading someone else's comments (i think Bills) about being able to check you engines torque through 1551 (and i think VAGCOM) I decided to try it at work today. And guess what......
It works!
In measuring value 120 you can check your engines torque at what rpm so with the correct equation you can work out BHP!
Very handy!
Tried on a 1.8T Audi A6, The display said 220NM of torque and the book said it should have 210NM (Had done 70000miles) hence the higher figure.
Bill, I think this will be particully usefull to you to check for your lack of power without expensive rolling road time.
And is a easy way to check power output!
Excellent.
I still have'nt had time to try this... Got to do so now though.
Thanks for confirming it to me.
regards
Bill
On the 1551 you normally have 4 figures when displaying a display group number (ie 120 as you have stated). Is it obvious which one is Torque and what do the other figures represent??? I do have access to a 1551 but unable to get any other info from VAG without going to a Dealer. I need to check the figures on my newly aquired Ibiza Cupra before it is APR chipped.
does any1 know if this also works on the new vas5051 computer as i find it easier 2 use than the 1551/52.
it's nice 2 have a big screen 2 look at:D
thanx
ben
Steve3961
04-01-2002, 21:05
5051 is a glorified 1551 so i think it would work.
The torque is display group 3 in channel 120 on function 08 (read measuring value) on engine electronics.
Hope this helps!
ibizacupra
05-01-2002, 18:05
Well I have been testing and datalogging today on my "210" Ibiza.
the figures measured from block 120 via VAGCOM confirm the figures measured on the RR remarkably closely.
Summary of runs lb/ft test gear
Max bhp @rpm Max Torque @rpm gear ratios
Run#1 185.7 4960 214.0 2960 4th 1.029
Run#2 180.3 5040 205.3 2760 4th 1.029
Run#3 189.4 4880 212.5 3160 3rd 1.308
Run#4 172.5 5400 209.6 3000 4th 1.029
Results can be seen on my website here> http://www.badger5.demon.co.uk/bin/dynoplot-vagcom2.pdf
Anyone want to comment on these results?
The same figures keep appearing...... Are these going to be dismissed as well? VAG ecu not outputting the right figures perhaps? (sarchastic head on there)
Same shape torque curver to the RR results.. > http://www.badger5.demon.co.uk/bin/dynoplot-1.jpg
http://www.badger5.demon.co.uk/bin/vx51hkk-dynoplot1-halfsize.jpg
http://www.badger5.demon.co.uk/bin/vx51hkk-dynoplot2-halfsize.jpg
I would like to know how the ECU measures the torque output though.... cleaver, but how? Direct? Indirect via calculation?
regards
Bill
chungster
05-01-2002, 19:10
My my........2 different ways of getting some figs....and both give the SAME fig (there or there abouts).
This is now very interesting.......
I don't know what to say Bill......so i'll stay stum for now.
ibizacupra
05-01-2002, 19:22
Originally posted by chungster
My my........2 different ways of getting some figs....and both give the SAME fig (there or there abouts).
This is now very interesting.......
I don't know what to say Bill......so i'll stay stum for now.
The really cleaver bit is the fact the factory ecu has the ability to measure or determin its torque output... Amazing.. Block 120 is described as part of the TCS system measurements.
Fair play to VAG.. they have a very complex ecu.
i keep going round in circles and getting the same end result.
Bizzar or what !
i like the torque figure and its delivery.... seems to be at the expence of the bhp though. Other chips seem to have another 30-40lb/ft of torque again though...
hmmm. The plot thickens.
Bill
ibizacupra
06-01-2002, 00:22
Here's a posting from a knowledgeable guy on how the #120 block works. Works it does though.
regards
bill
written by johnS on VWVortex 1.8T forum.. (http://forums.vwvortex.com/zerothread?id=179853)
VAG-COM numbers are net flywheel torque consisting of the force generated in the combustion process minus engine frictional losses, gas-exchange losses and torque required to drive ancillaries. Some here may not realize it but the torque values are not directly measured but are derived based on engine parameter inputs and known outputs. Engine speed, air mass, inlet temperature, barometric pressure, air pressure before and after the throttle, coolant temperature and run time are measured. Cylinder charge dilution, inertial effects on charge air and fuel, engine friction including pumping losses and ancillary drain are modeled based on test stand data. The data includes values for exhaust backpressure. Fuel delivery, throttle position and ignition timing are commanded. All of this is used to estimate the net torque generated by each cylinder firing. The model uses manifold pressure and engine speed in part to estimate pumping losses; engine speed, coolant temperature and run time to estimate engine drag. The cylinder charge air flow estimate includes adjustments for delays based on the pressure before and after the throttle along with throttle angular velocity and current throttle position. This also goes into estimating fuel delay. Intake storage and release requires additional estimates of intake port and valve head temperatures (derived from intake temp, coolant temp and run time) as well as the change in manifold pressure. Charge efficiency adjustments are made based on backpressure which itself is adjusted based on barometric pressure along with manifold pressure, engine speed and valve timing. Combustion efficiency is adjusted based on air temp, coolant temp, air/fuel ratio, charge dilution and ignition timing. The controller is a torque based management system so every effort is made to accurately derive its value.
Chassis dynos tend to show lower values than VAG-COM, or for that matter, actual road values for a number of reasons.
1) Driveline losses including tires (tire losses are greater on a roller than on a flat road).
2) Static loading and inertial coupling of the dyno with the car.
3) Air flow over radiator and intercoolers. Too low a flow and the drop will be much more than just the density change of air due to temperature. Ignition timing, fuel delivery and charge pressure all interact detrimentally with increasing temperature.
Test stand data tends to show higher numbers. When I did test stand dyno runs 25 years ago, engine coolant was supplied by city water and circulated by an external pump, draft air flow by an external fan and a metal hose connected the exhaust manifolds to the intake of an exhaust blower for evacuation out of the dyno room. I don't know to what degree this "cheating" is done with today's numbers. In prior years they even motored the engine and took those numbers to add to the output numbers.
[Described is how the Bosch ME-Motronic ECU works on the Audi TT. Not all ECUs have the same number of inputs. Your torque estimate may vary. See manufacturer (or look under your hood) for details.]
johnS
Very interesting....
Where do you get VAGCOM from? Is it just software and a special lead?
How much does it cost?
I know that you can see loads of stuff on the centre console if you put it into diagnostics mode, including an accurate speed display (Unlike the dash speedo!), but I guess it would be hoping for too much to get a Torque readout! :)
So, now you have some more evidence, but what can you do with it? I'm not sure where you can go from here.... lets see what happens on the 19th.
Ben
ibizacupra
06-01-2002, 17:26
Originally posted by BenS1
Very interesting....
Where do you get VAGCOM from? Is it just software and a special lead?
How much does it cost?
I know that you can see loads of stuff on the centre console if you put it into diagnostics mode, including an accurate speed display (Unlike the dash speedo!), but I guess it would be hoping for too much to get a Torque readout! :)
So, now you have some more evidence, but what can you do with it? I'm not sure where you can go from here.... lets see what happens on the 19th.
Ben
I got my vagcom from www.ross-tech.com for $199.
The software is a free download, which runs some features if you have the lead ((I bought mine from ross-tech and it arrived in 2 days from the US - Well impressed)
The software is activated when you read a serial number form the downloadable software, and email it back to ross-tech, who then email back an activation code which opens the software fully. Its easier than I've probably described.
its impressive stuff.
I think I remember Mark_APR saying they carried this, so it might be worth a call to them, being UK based..
regards
Bill
Steve3961
07-01-2002, 19:29
This is not the sort of software that you should use if you don't know what your doing.
You can cock up a lot of things to do with your cars electics.
We get lots of cars come in because customers have played with things they shouldn't and suprise suprise car won't start afterwards.
Its also worth knowing that VAGCOM will log a code into the control unit that it is interegating and Garages can see if you have played with things.
And then its Bye Bye warranty. :eek:
ibizacupra
07-01-2002, 20:59
Originally posted by Steve3961
This is not the sort of software that you should use if you don't know what your doing.
You can cock up a lot of things to do with your cars electics.
We get lots of cars come in because customers have played with things they shouldn't and suprise suprise car won't start afterwards.
Its also worth knowing that VAGCOM will log a code into the control unit that it is interegating and Garages can see if you have played with things.
And then its Bye Bye warranty. :eek:
True, true.... This tool in the wrong hands without the right experience and information on how to use, "can" screw things up.
Personally I am not too curious o nhow to change stuff (or even ask why I would have to) so use the block read and datalog functions as they are Read Only and safe.
Beware it is'nt a toy... but it is one hell of a diagnostic tool.
I have'nt come across anything that mentions the code logged by the ecu that you mention... :eak: indeed if true!
regards
Bill
I was under the impression that the code you are talking about is more like a key, and a dealer can see if it has changed,
And i also thought that the Vag-com from ross tech actually was rather intelligent in this respect as it took the key so that it could read the codes, but when finished and logged out of the ecu, it puts the same dealer code back that it found when it logged in?
Or am i wrong in my understanding?, doesnt really matter to me anyway cos my warranty runs out very soon as i will be over 60,000 miles!!
I a garage noticed that you have a VAGCOM eventcode stored on the ECU then couldn't you just say that your car wouldn't start so you pushed it to a nearby garage and they attached it to some computer thingy?
Is one of the conditions of the warantee that no other garages are allowed to touch it?
Uwe@Ross-Tech
08-01-2002, 00:30
> This is not the sort of software that you should use
> if you don't know what your doing.
That depends on how you use it. If all you're doing is checking fault codes and looking at measuring blocks, it's pretty difficult to hurt anything (except the buggy airbag controllers documented on our ISSUES page).
> You can cock up a lot of things to do with your cars electics.
Sure you can, but you have to try pretty hard to do that.
> We get lots of cars come in because customers have played
> with things they shouldn't and suprise suprise car won't start
> afterwards.
To the best of my knowledge, we've never had a customer who made his car undriveable with our product.
> Its also worth knowing that VAGCOM will log a code into the
> control unit that it is interegating and Garages can see if you
> have played with things.
No, it won't. Doing things like reading and clearing fault codes and looking at measuring blocks doesn't transfer any traceable data from the tool to the car. On the other hand, using the Recode (07) or Adaptation (10) functions does. Nonetheless, if you leave the WSC on VAG-COM's Options Screen set to 00000, VAG-COM is extremely stealthy -- it puts back whatever WSC was there to begin with!
> And then its Bye Bye warranty.
I don't know anything about UK consmer/warrantee laws, but I can tell you that in the USA, that the above statement would be patently false. A manufacturer cannot "void" your warrantee, all they can do is to refuse to pay for repairs IF they can show that the damage was caused by the consumer rather than a defect.
-Uwe- http://www.Ross-Tech.com
ibizacupra
08-01-2002, 09:18
Thanks Uwe.
Confirmation from the man himself.
I think the product is superb personally... It allows you the customer to confirm and check things and not to be a slave to the dealers, as they are the only ones with the kit.
We all know some dealers are better than others :D
If have VAGCOM and don't have the information on how to adjust things, then my advise is don't try.... Read blocks, clear DTC's, is easy and safe.
regards
Bill