Proposed S2/RS2 Performance Test & Database

[Rusty]

As discussed in the latter stages of this thread, a few of us thought that an S2/RS2 perfromance test similar to that of the S4 FATS time would be a most useful metric. The idea being that we get a database of mods and some real world performance times.

There are a few issues, firstly FATS uses VAGcom, secondly that 3/4/5 are different between 3Bs and the rest and thirdly that using 3rd+ means silly speeds, the top in an ABY in 3rd is 96mph ish and in a 3B it's 100+, 7k is approx 90mph (will be nearly 100 indicated), 4k approx. 50mph, how many places are there to safely do a 50-90? Only the country's private test tracks are suitable for that. Puls you'll need to do multiple runs to iron out inconsistencies.

So, as a proposed soultion:-

• Second gear (virtually the same for all S2/RS2 cars, guess S4/6 too).
• Speed between 40 and 65 mph (simple to test this and means 4k to 7k rev range).
• Use of GPS or accelerometer timing device (enable use of Racechrono on any GPS enabled phone).

A few notes:-

• I have been trying a few 30-60 runs and let the car drop to 1500-2000 rpm and then sharply apply WOT and hang on to the rev limiter.
• I would suggest that 6 runs are taken, the highest and lowest runs are deleted and then the remaining 4 are averaged.
• If there is a large spread in the results then it is worth checking that you are doing things in the same way.
  Expected times are around 3s for a chipped S2 so your measuring device will be more accurate with a higher refresh rate.

There are a few other threads that relate to this:-

Cheap Performance Meter - for those looking to measure performance on a budget.
Real World Performance Comparison - a previous thread with some 30-60 times.

Suggest logging the data using:-

Car description:
Modifications:
Tyre size:
Ambient temp:
Estimated bhp:
Estimated ftlbs/Nm:

Runs:
1 -
2 -
3 -
4 -
5 -
6 -
avg (mid 4 runs)

What do we think?

Oh, we also need a catchy name for it

Something like

SPOT - S two / rs two PerfOrmance Test
SPAM - S two / rs two PerformAnce Meaurement

SPAM test, I like that

[dest]

Surely using GPS or similar could bring too more posisibly of inconsistant results?
If someone has their GTech setup incorrectly then it could throw all the results out?
You cant go wrong with Vagcom data, so why not use that and just have 2 seperate databases for ABY and 3B

[GazzaG60]

well my vagcom data would be pretty useless along with Vas, S2Martyn and max to name a few.

also a bigger turbo car will get trounced by dropping to 1500rpm then WOT in 2nd.

not having a go, its a good idea in general but collecting (accurate) results will be hard.

you may find the list ends up being standard and homefry cars along with the odd mrc only

[AndyP]

You cant go wrong with Vagcom data, so why not use that and just have 2 seperate databases for ABY and 3B

I'm sure the 3B ECU does not have this function.

[Rusty]

No method where many different users are doing the measuring is ideal, even using VAGcom there are errors in interpolation and user inexperience. I think this is a good start, hence posting it up as a starting point. Using 3rd means that speeds are higher although people with larger turbos won't cry as much but some will still have issues.

[S2central.net]

You are right on the 3B front Andy - very limited logging on VAGCOM there.

I am realistic enough to know that one mans GPS data is not going to be really comparable to anothers cos of effects of weather, weight and of course how flat the road is. We should try and standardise things as much as possible though so people can get best out of whatever method they use to quantify performance.

I would certainly like to do multiple runs with VAGCOM, GTech, Dynolicious and Racechrono for comparisons - maybe someday when there is nothing else to do.

[Greg_S]

If we can work some proper conversions etc out I will have a go at building a script to standardise the figures into one format

[Rusty]

Cheers Greg. As in the first post I proposed the data required, again, this is a starting point but no additions or deletions have been proposed as yet.

[A80Avant]

im happy to provide the perfomance box which is easy and straightforward for this

[EspenW]

True that bigger turbos will have more gain in higher gears.
A K03 equipped car will only show 10ftlbs and 5whp difference between 2nd and 3rd, but on my Netic E50 equipped RS2, the difference between gears is much bigger,
I put down approx 380whp/400whp/410whp in 2/3/4th gear respectively, and a much bigger difference in peak torque between the gears, but 2nd gear covers real world speeds. The point is to have the interval start at approx 4000rpm and then go to redline. This is the rpm range that is used when pushing the car. Sub 4K performance only comes into play when you are stuck in a lower gear, like starting from a standstill or passing someone without downshifting. Once you shift out of the starting gear, your revs will not drop below 4K on the subsequent gear changes (unless you shift real slow). Performance between 4K and 5K is important though, unless you extend the powerband by a similar amount of rpm. It is all about average power over the rpm range that is used per gear.

[Rusty]

40-65 is very close to that 4k to 7k range, as discussed before.

[EspenW]

Yep, that is approx 4200 to 6800rpm with the CGR and CRB transmissions

[Rusty]

Redline (7400 RPM) in 2nd measures as approx. 66 mph on my GPS (72 indicated) so I make 65 a bit more than that, I make the figures:-

7400/66 = 112 RPM/mph

112 x 40 ~ 4480 RPM
112 x 65 = 7280 RPM

The problem with 2nd is that 40-65 takes around 2s in my car, not really long enough to measure small changes...

Using 3rd gear and ~96 mph GPS (103 indicated) @ 7400 RPM and a desired 4k to 7k band I calculate:-

96/7400 = 0.0130 mph/RPM
4000 x 0.0130 ~ 52 mph
7000 x 0.0130 ~ 90 mph

Thus, a 60-90 GPS in 3rd (~ 4600 - 7000 RPM) might be a better measure but that does involve a bit more care w.r.t. road selection . Incidentally, this is very close to the FATS measurement .

EDIT:- just checked and 60-90 is around the 5s mark so a fair bit more time to identify differences...

[EspenW]

Yep, the B5 boys probably picked approx 60-90 for a good reason, ie to get a reading that would be comparable to the results off a dyno.
I use both 2nd gear pulls and 3rd gear pulls for tuning and adjustments, but I can plot curves and spot minor differences, so that is helpful compared to just relying on time differences. 40-65 in 2nd is usually in the 1.6s range, while 60-90 in 3rd is usually in the 2.7-2.8s range. Very consistent between various logs, so one should definitely be able to spot trends using time only.
I thought GPS speed readings would be dead on accurate, but that was until I tested with two GPS units at the same time (Garmin and Satmap), and they did not agree 100%, especially during acceleration. Something like the Racelogic Performance box will give correct speed, though.
I use this gear calculator for finding the relationship between rpm and speed:

http://www.scirocco.org/gears/

Take readings from a few different rpms and average the outcome.
Circumference will change somewhat on a loaded tire, but at high speed, this should be small, since actual tire growth is seen at very high speed.

[Rusty]

I had a look and the S4 gearing is around 7% longer in 3rd than the S2 but the S2 has a higher rev limit. The FATS run is very close to 60-90 so I had a look at some old data, that's around 5s on my car and starts at just under 4k5 RPM and rises to 7k RPM, those figures should suit most cars and if they don't then some left-foot braking should help a bit