A/F Ratio

[__B3NNY__]

Just been playing with the ross tech A/F ratio calculator, I was just wondering what the results should be for our cars to be running pretty much spot on?

Heres my results, bearing in mind that im running a 4bar FPR

	RPM	Load %	A/F ratio
	3000	119.5	17.75
	3120	164.7	16.53
	3160	186.5	14.71
	3280	191	14.15
	3360	191	14.28
	3440	189.5	14.22
	3560	184.2	13.05
	3680	182.7	12.40
	3760	181.2	12.61
	3880	180.5	12.75
	4000	178.2	12.46
	4080	176.7	12.78
	4200	174.4	12.76
	4280	172.2	13.52
	4360	170.7	13.38
	4480	167.7	12.92
	4560	167.7	13.11
	4640	168.4	13.77
	4760	168.4	12.60
	4800	169.2	12.83
	4880	169.2	13.34
	4960	166.9	12.93
	5040	168.4	12.67
	5080	166.9	12.85
	5200	166.2	12.56
	5240	164.7	12.73
	5320	162.4	12.37
	5360	160.9	12.75
	5440	157.9	13.02
	5480	157.1	12.77
	5560	154.9	12.49
	5600	154.1	12.62
	5600	154.1	12.71
	5680	153.4	12.98
	5720	153.4	12.33
	5760	152.6	12.52
	5840	151.9	12.65
	5880	151.9	12.79
	5920	151.1	12.55
	5920	151.1	12.79
	6000	149.6	13.15
	6000	148.9	12.80
	6080	148.1	12.68
	6080	148.1	13.03
	6120	148.1	12.87
	6120	147.4	13.24
	6200	145.9	12.77
	6720	133.1	18.35

 

[ChrisCurzon]

just a quick question bit off topic how did you do them where is the A/F cacualtor and what logs did you do to get them?

cheers

 

[__B3NNY__]

Its on the ross-tech site mate under useful off site links. you need to download the xls file then just copy and paste your date from block 002 into the blue field.

 

[JIMYU]

apparently 14.7 is stoichametric (the perfect mix)

 

[JIMYU]

here's mine for a comparison (the graph is a bit small tho). i'm on a 4bar fpr too.

http://www.seatcupra.net/forums/showthread.php?t=142867&highlight=air+fuel+ratio

 

[__B3NNY__]

So mine seems to be running abit lean... but thats best for torque? Yeh right! i got 240ft/lb out of my k03s last time on the rollers

 

[Daz_gibbo]

It's not lean, thats fine. During on boost conitions the mixture is going rich. This is fine.

 

[ibizacupra]

I would be VERY WARY of using this calculator on a remapped car with different fuel pressure regulators.. I have seen some bizarre and completely wrong figures on remapped cars.

Unreliable measurement on a modded car

 

[Daz_gibbo]

Search for a thread started by me way back for comparison. iirc someone did a comparison with Zietronics? and the calc did show a bit richer in comparison

 

[__B3NNY__]

cool cheers lads, ill take a butchers. The chap at JKM did say to me it was running a little lean at top end back in september at the RR day but said it was nothing to worry about. Out of interest what would be done to enusre a perfect mixture?

 

[ibizacupra]

proper wideband and logging/adjusting (unisettings/custom settings/lemmiwinks type programme)

 

[__B3NNY__]

right ok, Ive actully added 6.75 deg with lemmiwinks ive moniterd the CF`s while adjusting. Would adding timing do anything good/bad to the mixture?

 

[Daz_gibbo]

what you seeing in Block 020 with the additional timing?

 

[ibizacupra]

right ok, Ive actully added 6.75 deg with lemmiwinks ive moniterd the CF`s while adjusting. Would adding timing do anything good/bad to the mixture?

would consume more of the delivered fuel from earlier burn BTDC.
Not a massive effect from my own tweeks, but you do need to be able to log the actual numbers of afr to be 100% sure.

 

[__B3NNY__]

what you seeing in Block 020 with the additional timing?

This is what i got stright after the adjustments, ill proberly re-log either this week or next to see if it has changed after adapting.

This is running T9 with 6.75deg added with lemmiwinks.

'020				Group C:
Idle Stabilization	Idle Stabilization	Idle Stabilization	Idle Stabilization	
				TIME
 CF	 CF	 CF	 CF	STAMP
0	0	0	0	
0	0	0	0	
0	0	0	0	
0	0	0	0	
0	0	0	0	
0	3	0	0	
0	3	3	3	
0	3	3	3	
0	3	3	3	
0	3	3	3	
0	2.3	3	2.3	
0	2.3	2.3	2.3	
0	2.3	0.8	2.3	
0	2.3	0	2.3	
0	2.3	0	2.3	
0	1.5	0	2.3	
0	0	0	0.8	
0	0	0	0	
0	0	0	0	
0	0	0	0	
0	0	0	0	
0	0	0	0	
0	0	0	0	
0	0	0	0

 

[ChrisCurzon]

sorry if jumping in abit on your thread but mine looks abit worring i think even it its not to taken as exact?

RPM	Load %	A/F ratio
1400	38.3	18.84
1400	41.4	17.52
1400	42.1	18.93
1480	81.2	14.26
1520	91	15.51
1600	97	15.08
1680	103.8	15.35
1800	112.8	15.22
1920	124.8	16.42
2000	137.6	14.36
2120	153.4	14.25
2280	167.7	13.20
2480	186.5	11.69
2600	191.7	12.54
2760	185.7	11.78
2880	184.2	10.89
3080	187.2	10.41
3280	185.7	10.07
3400	185	9.95
3520	184.2	9.99
3680	182	10.07
3800	183.5	10.15
3920	185	10.07
4080	180.5	10.16
4240	176.7	10.24
4360	175.9	10.50
4480	177.4	10.93
4640	173.7	10.87
4760	174.4	11.29
4840	173.7	11.59
4960	175.2	11.99
5080	172.9	12.22
5120	29.3	1.87
4400	3.8	0.00
4680	154.1	12.35
4800	152.6	11.96
4840	153.4	11.67
4920	152.6	11.40
5040	151.1	11.29
5080	151.1	11.11
5160	151.9	10.87
5240	149.6	10.91
5320	149.6	10.91
5360	148.9	10.93
5440	148.1	11.22
5520	148.1	11.10
5600	146.6	11.13
5640	146.6	11.24
5720	145.9	11.41
5760	144.4	11.48
5840	143.6	11.62
5920	139.8	11.31
5960	140.6	11.49
6040	138.3	11.53
6080	139.1	11.72
6160	136.1	11.38
6200	132.3	11.38
6240	128.6	11.23
6280	126.3	10.87

 

[ibizacupra]

worrying or simply wrong calculations if your car is modded.
I have logged a few cars which dont have wideband (ibiza's) and the array of figures that came out were abysmally erroneous.

a/f 9.9:1 would stutter like a mofo overfueling like a biatch

 

[PhilW]

In benny's case wouldnt you have to take into account the fact hes got a 4bar on it, so it would be -13.5% iirc for the extra fuelling?

 

[ChrisCurzon]

a/f 9.9:1 would stutter like a mofo overfueling like a biatch

exactly what its doing on full boost at the moment.

 

[ibizacupra]

"bing!"