To VAG-Com users, FATS times database for the Euro S4s

[CliveH]

Oli,

I've put my timings (on the right) alongside yours - some differences, but not as different as Paulm's. I haven't included my airflow data, but mine peaked at 252. So why do you and Paul get such a significantly better FATs time??? (I'm weighing in at about 12.5st, so it's not that!)

3240 168.17 100 12 23.3
3480 182.94 99.6 10.5 12.8
3800 196.89 100 10.5 9.0
4040 207.14 100 10.5 10.5
4280 216.61 100 10.5 13.5
4560 228.22 100 9.8 12.0
4800 234.47 100 11.3 13.5
5040 237.89 100 12.8 14.3
5240 237.06 100 12.8 14.3
5440 238.36 100 15.8 13.5
5640 241.33 100 18.8 14.3
5840 245.36 100 19.5 17.3
6040 247.89 100 21.8 18.8
6200 249.08 100 21 20.3
6400 249.78 100 24.8 20.3
6560 247.06 100 26.3 21.0

[oliew]

Clive, im not sure to be honest, my fats time before the trip yesterday was slightly slower than yours, but my wheels are bigger so slows me a tad, and i have the miltek, so i guess it kind of evens it out, it wasnt too hot yesterday so maybe that was one factor, and also removing the fog lights maybe keeping the intake charge cooler??? i did this run after cruising at 70ish for a few miles so i guess the Ic/s were very cold!
not sure why the timing is more but you are running a few degrees midrange more than me! and mine seems to pick up higher towards 6500 ,but i know i cant really run any more timing at the moment my cfs are around 4/5 now with 97, maybe if i optimax it (every shell was out of it on my way down!!?!???) i can advance my timing with vag a couple of degrees. More testing is needed
This is why we put up the fats database on mrc so we can compare times with specs, i think theres lots of factors to contribute to the better times, we talked for a while and mihneas time was with a alu flywheel and lots and lots of advance plus better fuel than we are running for our times and no cats also both have airbox mods, paul i think your running no cats either for your time? also both paul n mihnea did their runs on 17" wheels, clive can you do a run on 17's to experiment? that would be good! ive not got the opportunity this week, but one of my fronts is very buckled cheers
Oli

[Paulm]

We need some clever person to put all our timing and boost onto a spread sheet. (way above me though)

Oliew is running less advance because he is running more boost, they kind of go hand in hand.

Oliew you say your Cfs are 4/5 is that in top gear or when you are doing your FATS run? I see on MRC's web site your time came down quite a bit once you removed your fog lamps and the tem was 4c lower. Interesting how temp and flow make such a diff.

Clive, yes I was running 17's and around 7c i thnik the temp was. i have the same wheels as you now

[CliveH]

Thanks for all that Oli.

I would have thought running on 99 would have given me a bit more advance. I wonder if it's worth trying a tank of Optimax...?

All my runs have been on 18" wheels with 235/40 tyres. I'm afraid there's no chance of me doing a run with 17's as I cant get them on over the RS brakes...however, as DavidT says, the increase in rolling radius is insignificant and unlikely to be a major factor.

Now to the FATs database on MRC - where do we find this...?

[oliew]

http://www.mrctuning.com/fats.php

everyone add your times!

[harperboy]

What i cant understand is why the size of the wheel effects acceleration other than the weight issue. As i see it, although it takes longer for each whole turn of the wheels, i.e the increased of the rolling radius, your car goes further per whole turn of the wheels. Surely this equals out to be exactly same accelration or distance travelled in a certain time, minus the slight difference in weight. I stand to be corrected as my knowledge is limited!

[oliew]

Harper, im going to do a 19" run and 17" run only difference being the wheels and see what happens.
Paul do you have 18's on then now? any chance to do a run say in this weather like 24degrees or so... just to compare
Ol

[JonnyX]

What i cant understand is why the size of the wheel effects acceleration other than the weight issue. As i see it, although it takes longer for each whole turn of the wheels, i.e the increased of the rolling radius, your car goes further per whole turn of the wheels. Surely this equals out to be exactly same accelration or distance travelled in a certain time, minus the slight difference in weight. I stand to be corrected as my knowledge is limited!

FATS is between 4200rpm and 6500 rpm so a change in rolling radius would
dramatically affect this. Normally you run a lower profile tyre when increasing
the rim diameter to keep the rolling radius pretty much the same (i.e.
going from 225/45/17 to 225/40/18 results in a negligible change in
rolling radius).

[harperboy]

Cheers Ol, as Jonny says though, what profile are you running.

Jonny, I still dont understand why the change in rolling radius effects time as you are rolling further per turn??? Excuse my lack of knowlege/sense!

[CliveH]

You have a valid point Sam (harperboy), but I think it's something to do with gearing, which is setup up on the stock (17") wheels.

No doubt someone will be along soon to talk some sense into us...

[JonnyX]

Cheers Ol, as Jonny says though, what profile are you running.

Jonny, I still dont understand why the change in rolling radius effects time as you are rolling further per turn??? Excuse my lack of knowlege/sense!

Because the test is between a specific RPM range, not a speed range. Firstly, we are
assuming the same vehicle but with different wheels (hence the gearing is identical). The
car will be travelling at a differing speeds at 4200 rpm with differing rolling radii. e.g.
the test on a car with smaller wheels may result in a speed range of 55-85mph, larger
wheels may result in 65-95. All other things being equal, I would expect to cover 55-85
quicker than 65-95.

[harperboy]

Right, I understand you now! Cheers for your explantion Jonny. Yeah, i expect that you woul get from 55-85 than 65-95.

[flashyg]

OK , Did these logs today. Brave!
Outside temperature was 30 .c very hot.
Car is rs4 mtm full miltec and 100cell dp/cats.
Running optimax with 3/4 tank.

I am not at all certain if my fats are good or bad but I feel there is definitely not much timing and question if this may be due to 50.c intake temps. Or possibly some scummy garages selling dodgy fuel?

Here are the logs.

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Group A: '020

Marker STAMP CF CF CF CF
116.24 0 0 0 0
116.57 0 0 0 0
116.9 0 0 0 0
117.23 0 3.8 0 3
117.57 0 3.8 0 3
117.92 0 3.8 0 3
118.28 0 3.8 0 3
118.64 0 3.8 0 3
119.01 0 3.8 0 3
119.38 0 3 0 2.3
119.76 0 3 0 2.3
120.13 0 3 0 2.3
120.51 0 3 0 2.3
120.9 0 3 0 2.3
121.26 0 0 0 0
121.62 0 0 0 0
121.98 0 3.8 0 0
122.32 0 3 0 0
122.65 0 0 0 0
122.98 0 0 0 0

1 Are these Cf's normal for optimax or am I getting duff petrol?
(you will notice poor ignition timing on the next logs this may help to figure out if it is the petrol it may be the heat )




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Group A: '003



Marker STAMP /min g/s % °ATDC


21.42 2840 112.03 87.1 19.5
21.72 3000 130.64 89.8 18
22.02 3120 151.42 92.9 15.8
22.32 3320 179.56 96.1 12.8
22.64 3480 205.72 99.2 11.3
22.93 3720 228.92 100 10.5
23.23 3920 238.06 100 10.5
23.55 4120 253.89 100 11.3
23.85 4320 260.14 100 9
24.16 4520 269.61 100 12.8
24.49 4720 276.5 100 12.8
24.82 4960 289.42 100 12.8
25.16 5120 286.86 100 12.8
25.5 5360 282.47 100 12
25.85 5560 295.25 100 12.8
26.21 5760 311.19 100 10.5
26.57 5920 315.25 100 10.5
26.94 6160 333.81 100 14.3
27.32 6360 328.94 100 13.5
27.7 6560 334.78 100 18
28.07 6680 343.67 100 18
28.45 6880 347.69 100 14.3
28.83 7040 352.78 100 14.3
29.21 7000 0 5.9 37.5

2 my peak timing here is 18 and average 12-14 is this because of the heat? or the fuel, or is it normal?

My Fats here are apx 4 sec is this right? I feel not hence the concern.



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Group A: '004


Marker STAMP /min V °C .c


22.99 2560 13.37 96 57
23.29 2600 13.37 96 57
23.59 2560 13.23 96 57
23.89 2600 13.37 96 57
24.2 2600 13.3 96 57
24.5 2600 13.3 96 57
24.8 2560 13.3 96 57
25.1 2560 13.37 96 58
25.4 2560 13.3 96 58
25.7 2560 13.3 96 58
26.01 2520 13.23 96 58
26.31 2520 13.3 96 58
26.61 2520 13.37 96 58
26.91 2520 13.37 96 59
27.21 2480 13.37 96 59
27.51 2480 13.37 96 59
27.82 2440 13.3 96 59
28.12 2440 13.3 96 59
28.42 2400 13.3 96 59
28.72 2400 13.3 96 59
29.02 2400 13.3 96 59
29.33 2400 13.3 96 59
29.63 2360 13.3 96 59
29.93 2360 13.3 96 59
30.23 2360 13.37 96 59

3 This is for ref on the intake temps to give an idea how hot it is.

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Group A: '115


Marker STAMP /min % mbar mbar


36.71 2400 46.6 1000 1010
37.02 2440 74.4 1570 1050
37.33 2520 85 2140 1120
37.62 2600 94.7 2140 1230
37.92 2680 103.8 2140 1330
38.22 2800 113.5 2170 1450
38.52 2920 124.8 2260 1590
38.83 3040 136.8 2320 1750
39.14 3200 153.4 2400 1950
39.44 3360 173.7 2460 2220
39.73 3560 189.5 2460 2400
40.03 3760 191.7 2460 2480
40.35 3920 191.7 2460 2530
40.64 4120 191.7 2460 2540
40.95 4320 191.7 2460 2500
41.27 4520 191.7 2460 2460
41.6 4720 191.7 2460 2430
41.93 4960 191.7 2410 2440
42.26 5160 191 2400 2420
42.61 5360 180.5 2430 2390
42.96 5600 182.7 2390 2380
43.32 5760 184.2 2350 2400
43.68 5960 184.2 2310 2370
44.05 6160 181.2 2300 2330
44.43 6360 180.5 2300 2310
44.8 6560 175.9 2290 2290
45.18 6720 171.4 2280 2280
45.56 7000 27.8 1000 2370
45.91 5280 100 2480 1280
46.26 5440 152.6 2410 2110
46.61 5560 179.7 2380 2390

4 I have shown my boost logs and they look well but as Minhea has said bigger boost in hot weather will cause lower timing. So do you think again this may be the cause? Does the boost look OK?





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5 This is a test i did in cooler conditions timing is still poor but 1.5- 2 degrees better and as a result the fats are 3.5 secs.
Is that a good fats for my state of tune?

Group A: '003


Marker STAMP /min g/s % °BTDC


596.84 3040 156.28 90.6 15.8
597.14 3240 186.08 93.7 14.3
597.44 3440 215.39 97.3 12.8
597.74 3640 245.44 100 13.5
598.05 3920 260.72 100 14.3
598.36 4160 261.19 100 15
598.67 4360 269.58 100 16.5
598.99 4600 294.58 100 13.5
599.31 4880 309.17 100 14.3
599.65 5120 309.83 100 15
599.99 5320 303.81 100 14.3
600.34 5560 321.33 100 12.8
600.7 5800 332.81 100 11.3
601.07 6040 344.67 100 15.8
601.44 6200 352.78 100 15
601.82 6440 354.86 100 13.5
602.19 6600 364.08 100 15.8
602.57 6800 364.08 100 19.5
602.94 6800 78.78 25.1 44.3
603.29 5480 274.44 100 21.8
603.64 5520 320.86 100 9.8


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6 why do some logs say AtTopDeadCent AND OTHERS SAY BeforeTDC?


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To all helping on this fats discussion board , thanks for your input.
It is painful when you feel things are not right.
Regards
G

[CliveH]

Lots of good stuff there Gordon.

I'm far from qualified to answer any of your questions, but just one thing, I'm assuming that FATs time is carried on the RS4 method, which is slightly different to S4?

[flashyg]

No Clive. Its based on the terms laid out in this discussion.
Logs and times are based on the 4200 to 6500 with WOT from 3k ish.

If any one can help the questions I am very grateful . Thanks in advance guys.
G