VAG-COM Measuring Blocks

[42TT]

Can someone tell me the block number for the following readings

Knock
Timming Curve
Air/Fuel Curve

Ive got vag-com and an RS6

[skiwi]

knock is 20 & 21 - specifically the retard chosen as a derivation from the knock sensors. all should be around the same.

there is no timing curve or air/fuel curve. these curves are, by definition, derived from a variety of basic parameters which are inputs to or outputs from the ecm.

what do you want to do? is it to do with your turbo questions?

[42TT]

I am having a chip written and the tuner has said to get the most oout of it he needs me to supply the above logs so he can write it to the car specifically.

Is there are place to log timming and a/f ratio under WOT?

[skiwi]

you need to start by plotting the pressure ratio and volume of air of the stock setup against load & rpm. that will overlay the compressor chart. you want to spec this so that the efficiency curve is acceptable at peak load (rhs of the chart). ditto the rampup needs to be to the right of the surge line.

if you increase boost, you move the line vertically, the job of the tuner is to ensure that the new curve still falls between the surge line and the line of acceptable efficiency. outside of this and you will get little boost (lhs of surge line) or very high temps (not enough efficiency). the rs6 turbo is efficient and crisp, but - going by the graphs, could handle a bit more boost...

still as lot easier to just buy a chip from a known reputable vendor

if i get some time in the next couple of days, i'll plot it myself against the b/w maps...

[42TT]

Well to be honest i trialled a well known vendors chip and returned it as i could not justify the money for the performance increase.

The tuner i am using is well known. What he wants is to see how my engine is performing under WOT. He wants to see the following readings during a 4th gear run under wot from 50km/h.

Timming
Knock
A/F Ratio
Boost
Volume of Air

What measuring blocks should i use?

[skiwi]

ok,

03 gives rpm, mass air (gm), load (%) & timing (btdc).

knock is 20/21.

boost is 115 #3,4: - specified and actual.

a/f will always be targetted @ maintaining a stoichiometric ratio of 14.7:1 there are no blocks for this - i suppose that you could work it out using "steam method" - using the timing...

[42TT]

How can i do this "steam method" to determine a/f at specific load/rpm sites

[FUngusmud]

You'll probably want to use block 2, field's 3 and 4 for MAF. Add them together. Block 3 is this, but maxes out around 360 when block 2 field 3 + 4 show the actual amount.

[42TT]

Can you tell me the M_B's to use to get the necessary data

[skiwi]

err, we have. but there is no way to get a/f ratio other than deriving it.

[42TT]

how do i derive it?

[skiwi]

actually, i'm pretty tired of this game. i think you need to get someone else to play....

hint: "please" and "thanks" work well most places to develop and encourage co-operation. in the absence of these niceties, a person often just appears rude...