Beyond FATS - Performance Testing

[MarkB]

All.

There's been a few topics recently about comparing different cars using FATS. Obviously this isn't going to work because of gear ratios and tyre size.

I propose a test in third gear between something like 60 and 90.

This can be done in VAG-COM. There is a but though. To get good values people need to check their speed via GPS. Wheel and tyre (and gearbox) changes will affect the speed the car is doing against the speed VAG-COM thinks the car is doing.

So run the car @ 60 via GPS speed and find out what VAG-COM thinks you are doing. Then do the same for 90. Put these 2 values into the acceleration test on VAG-COM and go for it!

Anyone up for it? Worth a go?

[CliveH]

Good one Mark

Yea, I'm up for it, but there is another "but" - can I borrow your GPS...?

[GrahamS4]

I'm in..........send my vagcom lead to..........

[MarkB]

Good one Mark

Yea, I'm up for it, but there is another "but" - can I borrow your GPS...?

Someone must have a TomTom near you. Haven't you got Sat nav?

[MarkB]

I'm in..........send my vagcom lead to..........

Someone must have a VAG-COM lead near you...

[CliveH]

Good one Mark

Yea, I'm up for it, but there is another "but" - can I borrow your GPS...?

Someone must have a TomTom near you. Haven't you got Sat nav?

Have SatNav+ in the car, but it doesn't tell me my speed...

Was just joking...we also have a BenBen (Ben's TomTom) in the S2, so we can use that.

Just thinking about the accuracy of this Mark - the person sitting in is gonna have to look at 2 screens (Vagcom & Tomtom) and decide what the respective speeds are - it's not going to be a perfect science.

[MarkB]

It's the best I can think of. Driver should be able to look at BenBen and even use cruise control to set the speed. Passenger then notes VAG-COM reading.

I did think about logging with GPS but the update just isn't fast enough

[CliveH]

Not knocking the idea Mark - it's a good one.

Now setting cruise (for those who have it) is a great idea as it stabilises the speed, well at least in theory, and will allow the passenger to read off both speeds with ease

[MarkB]

I've never liked the FATS run. Fine for the big boys but my little K03's just don't have the go all the way up to 6.5K

I'll try and get some numbers over the weekend. Be interesting if people post up their VAG-COM speeds for the 2 actual speeds (60 + 90)

It might even up the playing field a little for those running larger tyres/wheels. It will also show the performance advantage of the shorter geared RS4 box.

Let the games begin!

[CliveH]

Be interesting if people post up their VAG-COM speeds for the 2 actual speeds (60 + 90)

That's 150 Mark! We'll have to find a suitable airfield...

[MarkB]

60 & 90

[CliveH]

C'mon Mark - it's Friday afternoon - where's your sense of humour gone...?

[ZeroK66]

[quote="MarkB"]So run the car @ 60 via GPS speed and find out what VAG-COM thinks you are doing. Then do the same for 90. Put these 2 values into the acceleration test on VAG-COM and go for it![quote]

Good idea... but gearbox still be a difference on RS4's and S4's - so one may have an advantage in this test, but in an all out run the other may see the advantage of the different gearing. Again wheel size would make a difference as cars would be at slightly different RPM's - so that particular test may not be the most accurate. We would also not be using a great range of RPM and so not enough time to compare cars with different torque curves.

FATS has worked well for a long time. Why dont we all hire out an air strip and run against eachother - that would be fun

There are too many factors, FATS is as generalised as it can be - if you want precisely equivalent tests then they would all have to be run on the same stretch of road in the same weather conditions (humidity, temp, wind etc etc) - its all just silly. I think FATS is good enough.

The 30-130 test is a great idea, as it is real world, but I will do when I get access to an area where I can do those speeds legally, that would be an intersting test... but then gear change times, rpm changes etc etc all make a difference. Why this huge thing to put down FATS? There are only two gearbox sizes... only compare RS4's with RS4's and S4's with S4 boxes... simple?

One thing I would suggest is starting a new FATS run that uses a broader range of RPM & gives two times. Say one time from 2500 - 4200 and the usual one from 4200-6500 - this would satisfy those more interested in daily driveability of the car. Of course we still have all the same old gearbox issues, wheel sizes etc etc...

Only true test is all the cars on the same strip of road at the same time... but then different drivers, driver weights and wheel sizes, wheel weights blah blah all make a difference.

D'oh - lets give up and buy diesels? We can start comparing economy and find different reasons to why results may vary

[GrahamS4]

I think it is a good test. Real speeds, real times. Revs, wheels, gearboxes, even the car can all be different. That's exactly it, all those elements can differ but the test remains fair in the sense you are comparing apples with apples.

[CliveH]

What was that all about Leon...???

Have you hit the Friday night bottle already?!