What is your peak MAF reading?

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stimp
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Post by stimp » Thu Apr 06, 2006 7:28 pm

Kaygee's write up is very good. I still do not agree that air input is directly proportional to power out(it does have a strong correlation). The timing is very critical and using theoretical AF ratios is not always optimum. Prediciting an output from measured inputs is O.k but as the output is the main area of interest it must surely still be the best place to measure.
Without a rolling road how can you do a full power run through the gears and simulate max load scenarios. Good debate and interested in other peoples opinions.

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Post by buzzard » Thu Apr 06, 2006 7:42 pm

surely actual output measurement can only realy be measured with engine on a test rig
because pwer loss through clutch, gearbox, diffs, hubs (including brakes )and even through tyres will vary from vehicle to
vehicle ---rolling road to rolling road,----even the person doing the test.
where as a computer read out for an airflow through engine figure has less chance of being corrupted by any other resistance apart from computer reading the data

yes it is a good debate and i would also be iterested in other peoples opinions.
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Post by DavidT » Thu Apr 06, 2006 7:53 pm

buzzard wrote:surely actual output measurement can only realy be measured with engine on a test rig
because pwer loss through clutch, gearbox, diffs, hubs (including brakes )and even through tyres will vary from vehicle to
vehicle ---rolling road to rolling road,----even the person doing the test.
where as a computer read out for an airflow through engine figure has less chance of being corrupted by any other resistance apart from computer reading the data

yes it is a good debate and i would also be iterested in other peoples opinions.
Absolutely, an engine dynamometer is the way to do it but we don't really have that luxury (£1000 for engine out and in before you start testing it).

Best compromise measurements will be from a good independant rolling road and a good few cars and owners who have done other dyno runs, FATS etc to give sensible comparisons. Exactly what Brett Collins is arranging in fact.

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ZeroK66
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Post by ZeroK66 » Thu Apr 06, 2006 11:45 pm

Having just ordered my VAG-Com I will do a FATS run... didnt mean to cause a heated debate... just wanted some MAF readings as a rough guideline to how my car was performing :-/
Facelift Imola S4 | Cust K04's, Tubular Manifolds, 3" DPs->2.75" Catback | FMIC | PSS9 Coilovers + ARB's | Brembo 8-Pots | SS + DTS | 5??HP/475lbs/ft | 3.06S FATS on S4 Box

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Post by tartan_rob » Fri Apr 07, 2006 8:39 am

Okay guys. Disconnected my MAF last night and hey presto the car is running better now than before.....so fortunately my local dealer has one on the shelf and they are going to exchange mine for £70 odd.

It must have been going for a while...!
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ZeroK66
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Post by ZeroK66 » Fri Apr 07, 2006 9:16 am

Looking forward to your readings Rob :D - good thing you spotted the failing MAF... nightmare they are :(
Facelift Imola S4 | Cust K04's, Tubular Manifolds, 3" DPs->2.75" Catback | FMIC | PSS9 Coilovers + ARB's | Brembo 8-Pots | SS + DTS | 5??HP/475lbs/ft | 3.06S FATS on S4 Box

Sold: A4 (B5) 2.8 Quattro | Ivory Pearl
Melted: Corrado - IHI 1.8t: 343BHP

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Post by jeffw » Sun May 07, 2006 12:50 pm

325 on mine

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ZeroK66
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Post by ZeroK66 » Sun May 07, 2006 10:29 pm

Little history behind that reading would be nice Jeff ;) - what mods?
Facelift Imola S4 | Cust K04's, Tubular Manifolds, 3" DPs->2.75" Catback | FMIC | PSS9 Coilovers + ARB's | Brembo 8-Pots | SS + DTS | 5??HP/475lbs/ft | 3.06S FATS on S4 Box

Sold: A4 (B5) 2.8 Quattro | Ivory Pearl
Melted: Corrado - IHI 1.8t: 343BHP

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Post by Philws4 » Wed May 30, 2007 10:05 pm

Got 272 on mine :D
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shineydave
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Post by shineydave » Wed May 30, 2007 11:16 pm

Excellent dead post resurection there, 10/10
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Post by rolskii » Thu May 31, 2007 2:11 am

I got 320....

k04's, rs4 inj, i/coolers, fat h/gaskets, rs4 d/pipes, 3" milltek, mrc map, got a bipipe now, but time was on standard bagpipes ...
happy dayz .... party ....

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Post by Philws4 » Thu May 31, 2007 7:08 am

shineydave wrote:Excellent dead post resurection there, 10/10
Thank you Mr Dave, can i have a gold star. :wink:
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Post by S4TAN » Thu May 31, 2007 9:58 am

Excellent dead post resurection there, 10/10
2nd that - a gap of over 1 year between the posts - superb! :lol:

I get a constant 335 g/s on mine (maxed out the MAF reading on vag-com)
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Post by smurfbus » Thu May 31, 2007 12:58 pm

360 is vag-com max.

318-345 is S4 max

390 IIRC is RS4 max

I hit 450-470 depending on boost but I dont thing I can use that to calc real power. I think it much lower than dividing by 0.8

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Post by S4TAN » Thu May 31, 2007 1:05 pm

360 is vag-com max.

318-345 is S4 max
Really? Hmmm ... I've been told different! I don't doubt your word here smurfbus ... but it conflicts with what i've been told by my 'local tuner' ... :lol:
I hit 450-470 depending on boost
How are you measuring that if vag-com max is 360? Some other s/w???
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