What's your mapped MAF g/s Readings
- Thread starter Dan-Jnr
- Start date
I did a maf reading over the weekend to see if the car is mapped or not. 2009 S3 3rd gear pull highest reading was 232 g/s over 0.8 gives around 290bhp.
Seems high for standard but low for remap so not sure what's going on here. It has standard airbox on too.
Actual boost peaked at 2200mbar is this enough for stage 1 or standard
I've checked software flashes via VCDS in 01 engine and reads 0 so this makes me think it's standard but maf reading says different kind of.
Seems high for standard but low for remap so not sure what's going on here. It has standard airbox on too.
Actual boost peaked at 2200mbar is this enough for stage 1 or standard
I've checked software flashes via VCDS in 01 engine and reads 0 so this makes me think it's standard but maf reading says different kind of.
Last edited:
Flexiblemouse
Registered User
I'm not 100% sure but I think 290hp is about right for a mild stage 1 tune. Or it could be a strong engine with a couple of modifications you are unaware of.
It's hard to tell really, I've come from a mapped 2.0 tfsi stage 1 ko3 to this and does Seem quicker than that but not 50bhp not sure wether the Quattro is masking the speed smoothly.
Car has no modifications I'm aware of only thing I've changed is the DV from G to a D.
Not sure of any other logs or ways to tell if it's mapped really.
Car has no modifications I'm aware of only thing I've changed is the DV from G to a D.
Not sure of any other logs or ways to tell if it's mapped really.
I thought it was time to resurrect this thread as im now on APR 2+ and have done a little research with various intakes.
Current spec is
APR 2+
Milltek resonated system with 200 cell cat
Revo intake
GFB dv+
At first it flowed 270g/s with ltft @16.8 which is not good.
I worked out the ideal internal maf housing diameter from the various intakes I have including the standard oval shaped s3 housing and calculated it to be 63mm
The Revo measured 66mm so I fitted a sleeve inside the pipe and now I get............
303g/s and ltft @1.6
I'd say that is a result
Current spec is
APR 2+
Milltek resonated system with 200 cell cat
Revo intake
GFB dv+
At first it flowed 270g/s with ltft @16.8 which is not good.
I worked out the ideal internal maf housing diameter from the various intakes I have including the standard oval shaped s3 housing and calculated it to be 63mm
The Revo measured 66mm so I fitted a sleeve inside the pipe and now I get............
303g/s and ltft @1.6
I'd say that is a result
I thought it was time to resurrect this thread as im now on APR 2+ and have done a little research with various intakes.
Current spec is
APR 2+
Milltek resonated system with 200 cell cat
Revo intake
GFB dv+
At first it flowed 270g/s with ltft @16.8 which is not good.
I worked out the ideal internal maf housing diameter from the various intakes I have including the standard oval shaped s3 housing and calculated it to be 63mm
The Revo measured 66mm so I fitted a sleeve inside the pipe and now I get............
303g/s and ltft @1.6
I'd say that is a result
You have stock K04?
You gays most also calculate with increased ignition timming and other lambda values in a tuning file, that can make the promised power values. Say if one tuner says his stage 2+ file gives 360hp, that does not mean that measured air flow need to be 360*0,8= 288g/s.
Normal stage2+ g/s reading is 240-265g/s with correct maf housing and that is abouth max flow capacity on stock k04-064. Rest of power is made from increased ignition timming,correct lambda and good additional hardware.
Remember the /0,8 value is wery theoretical. Wery often abouth corect for a stock car. But rarely correct on tuned car.special if hardware is changed.
Normal stage2+ g/s reading is 240-265g/s with correct maf housing and that is abouth max flow capacity on stock k04-064. Rest of power is made from increased ignition timming,correct lambda and good additional hardware.
Remember the /0,8 value is wery theoretical. Wery often abouth corect for a stock car. But rarely correct on tuned car.special if hardware is changed.
Last edited:
Yes stock k04
The ltft trim value being at +1.6 means the air/fuel mixture is correct, so assuming the fueling side is ok, the maf calibration must be almost perfect.
Stock airbox with carbonio I've seen 270-280 g/s on APR 2+
The ltft trim value being at +1.6 means the air/fuel mixture is correct, so assuming the fueling side is ok, the maf calibration must be almost perfect.
Stock airbox with carbonio I've seen 270-280 g/s on APR 2+
Fuel trim looks wery good. Not good to know what APR maybe have done to work better with aftermarked intakes. If say your intake now is correct. 303g/s is wery good. that is TTE420 flow capasity.
Revo intake is litte of but is not normal to have 16.5% ltft with revo intake. So somthing tells me can be somthing else with the car or maf scaling in the software is not stock. normaly 66-67mm tubing works good if not any bends right before or after sensor. I have made many custom intakes and maf housings to use with OEM TTRS/RS3 for 2.0TFSI engine.
66/67mm outside diameter maybe.
It's not an APR issue, it's down to the intake manufacturers to make the housings as close to oem as possible.
The maf sensor only takes a sample from the airflow and then the ecu calculates the total flow from the overall cross sectional area.
Every millimetre over that affects the scaling and will give false airflow readings and will push the ltft's out
I have a few housings
The S3 housing cut out of the original cover, oval shaped but equates to roughly 63/64mm....trims are 3.5
An A4 housing which is 65mm....trims at 10.6
The Revo which measure 66mm....trims at 16.8
Itg housing which measures 67mm.....trims nearer 20.
It's not an APR issue, it's down to the intake manufacturers to make the housings as close to oem as possible.
The maf sensor only takes a sample from the airflow and then the ecu calculates the total flow from the overall cross sectional area.
Every millimetre over that affects the scaling and will give false airflow readings and will push the ltft's out
I have a few housings
The S3 housing cut out of the original cover, oval shaped but equates to roughly 63/64mm....trims are 3.5
An A4 housing which is 65mm....trims at 10.6
The Revo which measure 66mm....trims at 16.8
Itg housing which measures 67mm.....trims nearer 20.
We made a limited run of intakes with a full 3inch MAF housing and recalibrated the ECU to suit. A lot of the A4 boys who run GT30's etc run 3in MAF's that I've calibrated.
Rick
Rick
Normal tubing size used is 2.75inch. thats rough 69,85mm. CTS Turbo intake excl. use 2,75mm tubing and is known for wery correct fuel trim values. how deep the sensor sit in the pipe/housing and where on the pipe its located is as important for correct measurement,
the power output for a given mass air flow also depends on how much fuel is going in.
eg 250g/s of air at 12:1 air/fuel ratio works out at 332bhp, at 11:1 it's 362bhp
"brake specific fuel consumption" will also change the results. the 11:1 ratio above is 362bhp at a BSFC of 0.5. and at 0.55 it's back down to 329bhp. This value also varies at different RPMs
fuel also makes a bit of difference.
gunna log my flows tomorrow, be interesting to compare to my dyno run
eg 250g/s of air at 12:1 air/fuel ratio works out at 332bhp, at 11:1 it's 362bhp
"brake specific fuel consumption" will also change the results. the 11:1 ratio above is 362bhp at a BSFC of 0.5. and at 0.55 it's back down to 329bhp. This value also varies at different RPMs
fuel also makes a bit of difference.
gunna log my flows tomorrow, be interesting to compare to my dyno run
just been for a run out. air intake temp 13°c
ITG Maxogen intake.
peak air flow was 293g/s at 6280rpm
peak boost was 2760 mbar (1.76bar boost) at 4720rpm, air flow was 263g/s
using the 0.8 rule that's 366.25bhp. Made 365.4 on rolling road.
I did notice the air flow doesn't change smoothly, between about 3200-4200rpm it's erratic, and boost drops slightly - the engine sounds like it's stuttering the recirc valve or something too. is that normal for stage 2+?
ITG Maxogen intake.
peak air flow was 293g/s at 6280rpm
peak boost was 2760 mbar (1.76bar boost) at 4720rpm, air flow was 263g/s
using the 0.8 rule that's 366.25bhp. Made 365.4 on rolling road.
I did notice the air flow doesn't change smoothly, between about 3200-4200rpm it's erratic, and boost drops slightly - the engine sounds like it's stuttering the recirc valve or something too. is that normal for stage 2+?
Attachments
Last edited:
What you see at 3200-4200rpm is boost surge. the turbo compressor is working at the limit line(to high boost) and pressure is slipping back to the intake side. thats way you have the wosh wosh sound.
Flexiblemouse
Registered User
Dividing by 0.8 simply gives a reasonable estimate of power that really only applies to cars with stock MAF scaling, the estimate is uncorrected, and at the crank. In my opinion its as good as any other method, with a dyno you have all the driveline losses to guess at, a correction factor (one of several), then errors in calibration etc. The only 100% foolproof method is to dyno the engine itself, out of the car. Any other method is an educated guess.
Last edited:
