Logging accelleration with Vagcom

[newsh]

I remember reading recently on here about using Vagcon to log accelleration by recording the time taken to go a certain change in RPM in a certain gear. This would give a figure that could be used to compare with other cars and determine relative power.

Firstly can someone tell me the details of the test and secondly how to log with Vagcom because I've never done anything apart from pulling codes and doing output tests.

[newsh]

Found this bit, just need to know how to do the log..

Do a single block log from 4200rpm to 6500rpm in 3rd gear with Vagcom (even the £10 copy cables will do this). The time it takes, along with the weight of the car and driver will provide an excellent estimate of the real power. Make sure to be at WOT from around 3000 to 6800rpm to ensure that the entire 4200-6500 rpm interval is done with proper spool.

[EspenW]

Excellent! Great if we can get some more FATS data on the B4's.
Quite simple: Just go to "engine" and then "measuring blocks". Open for example channel 3 and log that.
Press "log", then "start" and "stop" when done. This will create an excel file that will be placed under "logs" in the vagcom folder.
Only log one channel, as that gives the best data resolution.
What you need is time vs rpm.
Go WOT from around 2500rpm in 3rd and stay WOT until well past 6500rpm.
The log will be saved in an excel file, and you can plug the data into for example MRC's FATS calculator.
Remember that the B5S4 3rd gear ratio is supposed to be 7% longer than our 3rd gear (but I suspect that at least some US spec S4s were shipped with RS4 ratios)
The B5 RS4 3rd gear ratio is the same as ours (for 6 speed boxes), so the RS4 data is directly comparable.

Note: in order to get the highest possible sample rate, go to "options" on the Vagcom main menu. In that, set "Blk int" to 25 and "Char int" to 0 for best resolution.

Test in a safe place, and make sure the road is as flat as possible. Do pulls in both directions if possible.

[Greg_S]

Did you have a go at this newsh? what were the results like?

[newsh]

Annoying .. Went out just now to do it and the laptop wouldn't connect, tried it on the coupe all ok, went back to the avant and tried with a different ecu, still no go, so there must be a broken wire on the black or white connector under the fuse box. It worked last time I did it before the latest work was done

[newsh]

Is there any way to test the wiring of the black and white odb connectors?

Is there a fuse?

[newsh]

Had a read of S2 Central.. Fuse 21 was blown.

The black socket is loose in its holder and tends to come adrift when unplugging the lead, it needs fixing in properly.

I will try and run the test again tomorrow.

[s2_wot]

This feature could be really useful, looking forward to see how it goes for you

[newsh]

Got a 4.55sec and a 4.6sec. Outside temp 10deg, engine temp logs at around 70deg. Pulls really well to 7k.

[newsh]

This puts me around 350 BHP according to S4 times but I have to correct the 7%.. so that would make my time around 4.9 which is still maybe 320 BHP?
Andy C has a time of 5sec and power around 300 so 4.6 is pretty good!


Spec is:
S2 Avant, stock apart from..
Hoffer76 K24 with Focus RS comp wheel
Hoffer76 Chipset
RS2 Inlet and Exhaust Manifolds
Stock Downpipe, gutted cats
3" Milltek


Also this was on Esso "Supreme" as its a bit of a drive to get V-Power

[newsh]

I'm seeing lambda of 1 at WOT, from doing some reading HERE it would sem this is too lean

[prj]

From what are you seeing the value?
Do you have a wideband on the car?

If you are just seeing it from VAG-COM, then ignore it, as the narrowband sensor is useless for anything other than showing leaner or richer than stoich.
I would check the AFR with a wideband though.

[EspenW]

In addition to my own RS2, I have FATS tested a B6 A4 1.8TQ Avant and a MTM tuned B5 RS4. Claimed power from MTM is 463ps and 580nm. Same 3rd gear ratio as the 6speed S2/RS2, but this RS4 had 20" rims and tires that made for approx 3% longer gearing (in addition to being slowed from rotational inertia).
8C ambient temp
1860kg test weight with two on board.
I had the Vagcom hooked up for the first 3 pulls, and could only get times around 4.5s. It laid down approx 340whp and 465nm during those pulls.
It started to pull better later, didn't have the Vagcom connected then, but the 60-90mph times from the accelerometer dropped by approx 0.3s, so FATS times would have been around 4.2s. During those pulls, it put down 365whp and 485nm to the wheels as best.
With driver only, times should have been just below 4.0s. Still slower than I would have guessed beforehand.

The B6 A4 1.8TQ did 8.4s FATS with the stock map and 6.5s with the BSR map. The A4 has a 3rd gear ratio that is 4% shorter than the S2/RS2

[EspenW]

Got a 4.55sec and a 4.6sec. Outside temp 10deg, engine temp logs at around 70deg. Pulls really well to 7k.

Hmm, I assume that is coolant temp from channel 1?
70degs sounds rather low, and if the car was properly warmed up, I suspect the thermostat might not be working quite properly. I see coolant temps between 90-93degs in my RS2 logs, 90-92C for the RS4 and 99C for the A4.

[newsh]

From what are you seeing the value?
Do you have a wideband on the car?

If you are just seeing it from VAG-COM, then ignore it, as the narrowband sensor is useless for anything other than showing leaner or richer than stoich.
I would check the AFR with a wideband though.

No I don't have a wideband, it was just from Vagcom. I need to get one really, been thinking about it long enough