What MAF g/s airflow have you reached

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Re: What MAF g/s airflow have you reached

Post by RS4POWER » Thu Oct 06, 2011 11:41 pm

Doug- any MAF logs before/after Gruppe M install?
Same with P/P assuming there was no need for carbon clean...

Stage 2 port/polish includes what exactly?

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Re: What MAF g/s airflow have you reached

Post by mutantfatcat » Thu Oct 06, 2011 11:51 pm

Looking good Doug.

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Re: What MAF g/s airflow have you reached

Post by S4Player » Fri Oct 07, 2011 12:05 am

Doug is then we first done mine? Doesn't flow that now I think it's a little 'carbon'd' up is my engine lol
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Re: What MAF g/s airflow have you reached

Post by Doug_S2 » Fri Oct 07, 2011 12:27 am

that was your last one danny.

i don't think i have dynoed a car before and after a gruppeM.

And i think everytime we have done a ported/modified manifold we have always cleaned the ports.
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Re: What MAF g/s airflow have you reached

Post by S4Player » Fri Oct 07, 2011 12:30 am

If that's the case then isn't the calculations a little off? Ill call 2moro regarding my car
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Re: What MAF g/s airflow have you reached

Post by Doug_S2 » Fri Oct 07, 2011 12:43 am

the calculators are a rough estimate. When you start forcing air in, it all depends on what the engine does with that.
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Re: What MAF g/s airflow have you reached

Post by S4Player » Fri Oct 07, 2011 12:47 am

Yeh just saying that would mean I made 620 but I only made 520 big difference. My engine must hate forced air lol and decide not to do anything with it.
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Re: What MAF g/s airflow have you reached

Post by LawnSausage » Fri Oct 07, 2011 1:14 am

My Peak MAF readings under various conditions:

Stock dirty: 149 g/s (dyno'd 291 whp) Temp 48 degs F
Stock Clean: 156 g/s (dyno'd 320whp) Temp 54 Degs F
Pig Pipes, PnP IM, Clean: 158 g/s (Dyno'd 328whp) Temp 56 degs F
Pig Pipes, PnP IM, Clean: 162 g/s Temp 36 deg F
Above plus JHM Exhaust, tune: 164 g/s (Dyno'd 359whp) Temp 85 degs F (I want to do this run again now that its much cooler, may be closer to 170 g/s now)

Linus:
Stock Dirty: 146 g/s Temp 48 degs F
Stock Clean: 153 g/s Temp 54 deg F
Pig Pipes Dirty: 152 g/s Temp 56 degs F
Linus Pig Pipes Clean: 159 g/s Temp 38 deg F

Jared:
Stock Dirty: 145 g/s Temp 48 Deg F
Pig Pipes Dirty: 148 g/s Temp 54 deg F
Pig Pipes Clean: 154 g/s Temp 56 Deg F

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Re: What MAF g/s airflow have you reached

Post by LawnSausage » Fri Oct 07, 2011 1:48 am

The really unbelievable thing from the data above is that it very clearly shows the MAF is affected by carbon buildup. The carbon buildup is affecting how efficiently air can be drawn into the cylinders, and doing the calcs backwards from MAF here lines up with nearly perfectly what the Dyno's are showing. I still have no idea how, with all the data, the 3k-8k pulls, the dyno's, etc., why Arthur you still deny Carbon Buildup causes power loss. Baffles me, except for some guess you have some financial interest by denying it exists. It clearly pisses me off someone so data driven is ignoring the data.

Take my reading above when the car was dirty. 149 g/s MAF in 48 deg F weather. Thats ~275whp given a 25% drivetrain loss. I dyno'd 291.
Then go back to when I was stock clean, almost same temps, actually a bit warmer. 156 g/s MAF in 56 deg F weather. Thats ~300whp given 25% drivetrain loss. I Dyno'd 320whp. Regardless of the actually end whp numbers, the important thing is the delta. calculated and measured whp both increased proportionally, almost exactly!

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Re: What MAF g/s airflow have you reached

Post by thedoluk » Fri Oct 07, 2011 9:10 am

Doug do you know how many g/s my car did in jan when it did 464.6
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Re: What MAF g/s airflow have you reached

Post by Rick_RS4 » Fri Jan 11, 2013 10:07 pm

just been out for a maf test after the carbon clean, when i first posted this i was getting 160, im now getting 207, not sure its totally accurate as working out the bhp from that would give me 500 bhp lol

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Re: What MAF g/s airflow have you reached

Post by adsgreen » Fri Jan 11, 2013 10:48 pm

My interpretation of what has been said isn't that carbon doesn't affect things but in the real world what that difference actually means.

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Re: What MAF g/s airflow have you reached

Post by nij » Sat Jan 12, 2013 1:58 am

Rick_RS4 wrote:just been out for a maf test after the carbon clean, when i first posted this i was getting 160, im now getting 207, not sure its totally accurate as working out the bhp from that would give me 500 bhp lol
How do you a MAF test? I have got a VCDS cable.
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Re: What MAF g/s airflow have you reached

Post by Rick_RS4 » Sat Jan 12, 2013 2:35 pm

In the engine tab open measuring block 3 then log 2nd and 3 gear runs from 3k to redline, you will see your highest maf
reading

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Re: What MAF g/s airflow have you reached

Post by Rick_RS4 » Sun Jan 13, 2013 12:04 am

adsgreen wrote:My interpretation of what has been said isn't that carbon doesn't affect things but in the real world what that difference actually means.

to me it doesnt feel faster, but it is smoother and the readings say it has made a difference

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