Tuning, Dynos, Power Figures Moans etc....

[Ryan_s3]

have you done any boost logs with vag-com dunc?

[DavidR]

have you done any boost logs with vag-com dunc?

I've not found VAGCOM to be particularly useful for boost logging. It's maximum reading is 2540 mbar, or 1.5ish bar in our usual language.

Most remaps are running to about 1.5bar peaks, anything more and you'll just get 2540 on VAGCOM but in reality the boost may be a lot higher.

[ChrisG]

My understanding is that Tyre pressure, ride height, spings and dampers etc etc will all have an effect on a rolling road.......

and presumably tyre width also. I'm sure all this has to taken into account in Germany if the tuners are seeking TUV approval - regulations are really strict. This should mean that 250 bhp advertised is 250bhp on all rolling roads (?) and certainly over the years I've also been told that 250 bhp in germany can be regarded as the minimum you are likely to see -- you know trade descriptions stuff!
S2 Tuner can you confirm this ?

Didn't Geoff Everett (AmD) work for Bosch ( & BMW) before he started AmD with Mike? In the early 1990s he was tweaking KE injection on a modified 80 Sport we had, obviously only the timing side as it was basicaaly mechanical, but talking to him at the time he seemed to know a lot about Mr Bosch's Motronic systems, ( although I know nathing ) . He was very quick off the mark with Digifant when it arrived.
(Anybody know what happenened to him, does he still live in Oddington?)

Presumably the making more power with less boost is because of the huge heat implications with high boost ( expotential isn't it ?)

[Ryan_s3]

hi dave ,
I know on the s3 the map sensor can only read up to 1.5bar(2.5bar sensor) so it's more likely the range of the sensor rather than vag-com itself.

have you done any boost logs with vag-com dunc?

I've not found VAGCOM to be particularly useful for boost logging. It's maximum reading is 2540 mbar, or 1.5ish bar in our usual language.

Most remaps are running to about 1.5bar peaks, anything more and you'll just get 2540 on VAGCOM but in reality the boost may be a lot higher.

[DavidR]

Ryan, I'm not so sure (but am happy to stand corrected)

I beleive the MAP sensor reads higher than that as certain remaps now incorporate a higher boost threshold for triggering the ECU limp mode. AmD will remap a car allowing over 1.6bar boost and reprogram the ECU limp mode threshold in order to acheive this.

The MAP sensor on a standard car will trigger soft limp at 1.5V, whether this relates to 1.5bar I'm uncertain.

The MAP sensor is also not the only pressure sensor monitored by VAGCOM. I was speaking to RossTech who led me to beleive that it was VAGCOM that was limited, rather than the ECU sensors.

[DavidR]

On my car I can run the boost profile in several different ways. All over VAGCOM 2540 Mbar, but only higest boost mode (peaking at 1.89bar!) will trigger limp mode. I would have thought that if the MAP was limited to 1.5bar then all modes will cause limp. The Alternative theory is that other pressure sensors (at I/C, or MAF air flow rate) are to play...

[ChrisG]

Perhaps your car had a light remap to trick the reviewers with it being a press car...

Dunc[/quote]

Feasible, told by Geoff that he did jobs for some of the guys at MK who wanted 'their' cars to go better. I asked about warranty reply was along the lines of not a problem for them was it !

[Ryan_s3]

Was told by mike at jabbasport that the map is rated to 1.6 bar but can be rescaled to trick the ecu so you avoid limp mode,also after 1.6bar a would think that the injectors are running at 100% duty anyway so thats as much as it can take irrespective of boost pressure.

ChrisG,
Wouldn't be suprised if mines had a little tweak although when i had it RR@d at AMD they said it wasn't there remap??Does geoff still work there?Will be interesting when i pull the ecu.

[DuncS3]

Geoff runs the company that supplied the one click and DMS automotive chipping systems - so he is still about...

Regarding boost logging, my car has had loads of logging and actual and requested boost has been fine - my map doesnt peak above 1.5 bar, more like 1.4 to 1.45 maximum. In fact I am sure they are posted on this site somewhere.

So I dont have a leak

Dunc

[S2tuner]

The S3/RS4 MAP sensor can only measure up to 2540 hPa or mBar. The ECU is also programmed for those maximum values. A 3000hPa MAP sensor out of a 1.9TDI 150 HP PD engine can be used with hardcore program code disassembling in the ECU.

IMHO there's not much point in going much above 1.45 bar on an S3, as the turbo is already not working very efficiently anymore. power and torque are all a matter of balance and compromise. If you run 1.6Bar at low revs, you'll get loads of torque, but at the detriment of power at the top end, simply because by the time the engine has reached 5500-6000 RPM, the intake air is so hot that you can't make much over 240HP.

The injectors duty cycle definitely has nothing to do with measured boost in an ME7 equipped engine, like the S3. The injector duty cycle is only calculated on basis of the air flow measured by the MAF and different fuel maps contained in the ECU. About limp modes and things like that, the ECU can be programmed so it never goes into limp mode, even at 2.5 Bar, it's a matter of programming and understanding the code once again.

Boost isn't all in power and power is also a matter of air flow and efficiency. This is what tuning is all about, and this is what certain people don't seem to understand. Even if I can tune an S3 to run 2 Bar at 7000 RPM, what's the point in doing it if the car is going to make lower than stock power? Same for 1.6 Bar at 7000 RPM or 1.6 Bar period, which is too much for me.


HTH,

Mihnea

[DuncS3]

That helps Mihnea, good to read your input!

Dunc

[bjacks]

Perhaps that's why your car doesn't ever give great power Dunc. I seem to remember comments on how the Revo cars always seemed to get really warm on the dyno.

Keep this up lads, very interesting thread.

Cheers

Ben

[DuncS3]

I dont think many Revo cars (RS or S) have given that great figures but I always put it down to that they manipulate the timing, which would be something that suffers on a dyno. I mean by this that Revo have fuel specific maps.

Maybe Revo figures are correct and its some of the others that are over quoting?

Dunc

[DavidR]

IMHO there's not much point in going much above 1.45 bar on an S3, as the turbo is already not working very efficiently anymore. power and torque are all a matter of balance and compromise. If you run 1.6Bar at low revs, you'll get loads of torque, but at the detriment of power at the top end, simply because by the time the engine has reached 5500-6000 RPM, the intake air is so hot that you can't make much over 240HP.

Interesting points, but ones that haven't quite worked out practically on my car.

On the same dyno, on the same day my car will make 265bhp (average) and 280lbft (average) running at 1.5bar mean. If I modify the boost to peak at 1.89bar and mean 1.6 then I get 275bhp and 330lbft (again the average of 3 runs)

The torque figure is accounted for by altering the N75 acutation, giving the 1.89bar peak figure at 3000rpm, and therefore making good torque, but holding a higher boost up past 5000rpm also yields a power advantage...

Mihnea, I spoke with you briefly at Star a few weeks ago at the RR, but can you confirm the mean and peak figures for your S3 maps? Can you comment on why the Leon Cupra Rs are getting apparently better figures (270-275bhp) at 1.45bar when compared with the S3s?

Thanks.

[DuncS3]

ohh I love this thread

Dunc