What is your peak MAF reading?

[JonnyX]

MAF reading is only useful if you know the timing and mixture

[s4woody]

well my map list,s 310bhp plus i have the milltek fitted and a few other tings so when i get the results of my rolling rd 2morrow i,ll let u no what sort of power/torque im seeing..although my mates m3 evo dnt stand a chance with my s4,and if i dnt show as much bhp as him then i,ll be really confused cos i no he has about 330bhp..

[SimonS4MTM]

Its all in the torque

[SimonS4MTM]

And driver skill of course

[s4woody]

oh i,ll second that 1..

[KayGee]

Mine delivers 320 g/s with the RS4 MAF with no correction figures. Eqiuvalent to about 400 g/s on a S4 MAF.

[ZeroK66]

Nice... was going to ask DavidT if he has a standard S4 MAF or RS4 MAF???

Thanks for your reading KayGee.

[KayGee]

Davids car has always been a good one....

[ZeroK66]

Does that mean he has an RS4 MAF?

[stimp]

JonnyX makes a good point about MAF readings. All they really tell you is how much air the engine is pumping through it. If you run retarded ignition at max revs you can get high MAF readings and minimal power. You still get the boost pressure and the engine is pumping at the same rate just really low power. This is partly how the rally cars run the anti lag system. Withou knowing that your fueling and igntion are optimum there is no real certainty of expected power only a rough prediction.
A dynomometer(rolling road) is the only way to accuratley tell what power you have. Alternatley just open excel guess some numbers and plot your own charts, whatever makes you happy......Here in Devon avoiding the cow muck is the real issue.

[s4woody]

i did look at the pod and i believe he has an RS4 MAF..

[DavidT]

Yes I have an RS4 MAF now, If you look at the FATS thread, there are posts showing the S4 MAF at its maximum of 336 at high revs, hence the swap.

[KayGee]

Rolling road will only give you a rough prediction also, in some cases really rough, and they cost you money. Vagcom and a FATS or MAF test are free of charge and in most cases just as "accurate".

In regard to MAF readings they are a good indication as they will produce the same ballpark figures for a given state of tune. MAF reading also have the advantage of being real world and not relying on an electric fan to pump air into your intake and keep your intercoolers chilled. Lastly your not relying on the dyno operator. I've yet to see a MAF reading that is not a good indication of the cars performance.

If the cars timing or fueling is off it will not be pulling in the same amount of air and the MAF value will be lower.

After spending a few hundred pounds on dynos in the past, I personally don't rate them as accurate or rely on their numbers. They are a useful tuning aid and good for a multi car comparison.

.....just my 2p

[ZeroK66]

I have said in earlier posts I fully understand the effects of ignition timing, knock & fueling to what level of performance we get out of our cars for the volume of air entering the engine and I know this is only an estimate... but it does seem to be a fairly good indication of how the car is running.

Seems my car is running about 10 points higher than other equivalent cars (MTM & Catback) - so I am pleased with my results. I just was hoping for more with the gutted cats... and wanted to see from this post what others were getting.

Very keen to see what Rob's results are!!

[stimp]

Kaygee :-="If the cars timing or fueling is off it will not be pulling in the same amount of air and the MAF value will be lower."

Really , if you are driving the turbines so as too achieve the same ultimate boost pressure and at the same engine revolutions why would you see a change. I agree that the MAF reading is a good indication of the capability of an engine to pump air and thus a reasonable indicator of it's peak performance (and indicator that all is still well since last checked) but struggle to find much more use than that.
How do you use it to plot the power through the rev range, can you chart it so as to maximise the area under the curve and produce the best performance at any revs or is it only wide open throttle only. The dyno is not just for getting some peak number, you can check power at any point in the rev range, part throttle, WOT, through the gears etc. It's use in gaining valuable data are huge. I personally don't think you can get that info with what is nothing more than an airflow meter. It's one of the inputs into the engine system, there are so many others, timing fueling, temperature oil/water/air etc. For example, imagine trying to produce a map without being able to measure if the engine likes the ignition timing advanced or retarded at that exact rpm, it may prefer to be slightly lean at certain points richer at others. It's impossible to do it properly without being able to measure the output whatever people say.
Uuummm, I like dynos so there. Thanks to there awesome spinning talents both my Road and race bike are responsive, quick and smooth and therefore they are my friends.......