What blocks to measure on vag com to check the mapping?

S3 Paul

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Ive got a few days off work and have planned a few hours recriational driving :)
I keep reading that people log some of the measuring blocks on vag com,
Well which ones give an indication on how well things are going?
What figures should i want to see from say... lambda?
 
well.....

it's been said many a time, that in the VAG 20vt engines, the bhp is roughly equivalent to MAF/0.8, where MAF is the maf log of air mass in g/s.

so if you're drawing a peak MAF reading of 200g/s, divide that by 0.8 and you get 250bhp....

it seems fairly accurate, as from what I've read a standard S3 tends to peak at 170-175g/s, which is 210-220bhp....
 
I want to check the fueling ( havent wired my wide band gauge up yet ) Also i think ive read about people looking at what timing the car is running.
Also now ive fitted the front mount cooler i would like to know thats doing the things it should be...
 
take a look at the various blocks, starting from 001 onwards really, and it'll show you all the things it's capable of logging. I think the numbers of blocks vary depending on shareware/full versions, but I was quite easily able to log Inlet temps and BTDC timing values, as well as loads of other things.

Just have a play viewing different blocks until you find stuff you want to log!
 
try blocks:
001 - will tell you how much fueling the ECU is adding/taking away
031 - will tell you AFR
115 - requested boost v actual

and check 032 after a run to see what the adaption values are... way from

For more blocks and an explanation, http://www.ross-tech.com/vag-com/m_blocks/

<tuffty/>
 
It will tell you AFR but not how much the ECU is compensating and what the adaption values are plus it doesn't 'log'...

Generally speaking you are looking for a value of 0.8 ish under boost, anything higher and its getting lean...

Find a private stretch of road and floor it from around 2k to redline in third logging blocks previously mentioned and see how block 031 looks under load as this will tell you if your fuelling is right. Reference that with block 001 to see if the ECU is fighting to correct the fuelling, you shouldn't see much swing between +\- values.

Block 032 at the end of a run will tell you what adaption values the ECU has applied to keep things in check and will indicate if the map isn't providing enough fuel or too much.

(Bill, please correct me if I am talking crap...)

More info on AFR...

http://en.wikipedia.org/wiki/Air-fuel_ratio

<tuffty
 
Also i think ive read about people looking at what timing the car is running.

Block 020 for timing pull IIRC

Also now ive fitted the front mount cooler i would like to know thats doing the things it should be...

Block 118 will give you IAT's

<tuffty/>
 

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