Hi
First post after being a lurker for a little while so here goes... bit of background first...
I have a 2001 Audi S3 that I have done a big turbo conversion on... the spec is essentially as follows..
1.8 20v (AMK), std bore/stroke, AEB head and Supertech valve gear std cams, GT3071r, 0.63 hotside, Tial wastgate, Siemens Deka IV 630cc injectors, 3bar FPR, std S3 MAF housing and sensor, FMIC etc...
My ECU is an ME7.5 (wideband and EGT probe)... I have been working on a base file to get the injectors dialled in and have so far found a few bits of conflicting info regarding the calibration data for these injectors... has taking a me a few attempts to get KRKTE close but think I am pretty much there now but have a few questions...
I have read S4 wiki inside out and having wide band makes it a bit easier to get WOT sorted on the road using block 001 in VCDS and checking Lambda Control... I have set up both LAMFA and KLFBTS with suitable fuelling and have set TVUB according to a spec sheet I found here:
http://siemensdeka.com/specsheets/FI114961cs.jpgms | | volts |
1.441 | | 8 |
0.921 | | 10 |
0.758 | | 11 |
0.636 | | 12 |
0.518 | | 13 |
0.409 | | 14 |
0.312 | | 15 |
...although this conflicts with the data on the link here...
http://injector-rehab.com/shop/lag.htmlms | | volts |
0.83 | | 10 |
0.64 | | 11 |
0.5 | | 12 |
0.38 | | 13 |
0.28 | | 14 |
0.17 | | 15 |
Wasn't sure what to believe but went with the former rather than the latter... I used the 34.125/630 method initially but WOT was pulling a lot of fuel so after a lot of trawling and reading (mainly on Nef) I used another spec sheet from the siemens deka site (
http://siemensdeka.com/specsheets/FI114961.jpg) which suggests that in fact the injectors are 668cc @ 3bar and the following useful post on Nef
So here's my math on this, which I believe to be correct. (which I will be adding to my "theoretical" DIY/reference soon)
Rated vs. Operating pressure:
If you're AWT has 260cc injectors:
260 @ 3Bar (43.5psi) = 260cc
260 @ 4Bar (58.0psi) = 300.22cc (assuming a 4bar FPR that I believe comes stock on your car)
Conversion given n-heptane (the testing solution for injectors valued at 0.684g/cc Density):
300.22 x 0.684 = 205.250 g/min
50.2624*Vhzyl / Qstat
Vhzyl = Displacement/Cylinders = 1.781/4 = 0.44525
Qstat = Injector value @ operating pressure = 205.250
--50.2624*0.44525/205.250
---22.3793336/205.250
Calculated KRKTE= 0.10903
Your stock value: 0.10478
Your calculated value: 0.10903
Technically, thats a 4% final difference in injector calculation, not too far off but enough that I would want to change it.
This got me to a KRKTE of 0.04933 and a WOT run looking like:
Now... maybe a little tweak and I can get that a tad better but here are the questions...
Given that my LTFTs are hovering around mid 3%, is it better to tune FKVVS (mine isn't set to 1's like some of the other files on here) and/or TVUB? Due to the conflicting info on the 630's do I believe my TVUB settings to be correct? I have spoken to a friend who tunes for a living and I have no reason to disbelieve him at all (I know he is a member on here) but I thought it would be nice to get other people views on an approach to this
I have access to a dyno where I can do steady state across load sites but not sure if I am chasing the impossible of if I will get some progress from it...
Any advice is welcome
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