Stage 3 Homebrew fueling UPDATE. Airbox mod and new Lemmisettings: (BWW)

Mike2kS4 · 08-20-2004, 11:33 AM

Check out the below link for my initial post regarding my homebrew fueling for my K16/K04 Hybrids.

I figured that I may be getting higher MAF readings because the OE airbox has a bottleneck of about 3.25" between the MAF and the filter element. I ran a 3 5/8 holesaw from where the MAF meets the airbox down to the chamber of the airbox. This removed about 200 degrees of the circumference of the airbox outlet. Using blue painters tape, I formed a smooth transition between the MAF hole and the airbox chamber and covered it with JB weld. I then painted it black.

To my surprise, this mod made a significant difference, lowering my g/s by about 7% throughout the rev range. I had to richen the mixture commensurately.

Top view of the JB welded portion, the O-ring is insurance against the clips popping open. This setup has NO SCREEN.

View from the side. Up close it looks like crap, but with the hood open it's not obvious at all.

As this picture shows

Above are my new 'winks settings, used to compensate for the lower MAF readings. Again, YMMV on these settings. I lowered the timing from my previous settings because of heat soak and 95 deg ambient lately.

Logs of my MAF and Timing. Excuse the sparse data points. I was also logging O2 values and adaptation. .875 and bouncing above and below 0 at cruise and idle

Key note: My MAF peak now reads 20 g/s LOWER. Which gives me plenty of resolution for high-boost work!

http://forums.audiworld.com/s4/msgs/1736997.phtml

Funkweasel · 08-20-2004, 11:37 AM

its a weird flow effect of the new airbox connection or something else?

Mike2kS4 · 08-20-2004, 11:40 AM

And my restrictive IC's even make their job easier.

Mike2kS4 · 08-20-2004, 11:45 AM

The rising g/s slope isn't really that drastic if you look at where the data points start and end.

Funkweasel · 08-20-2004, 11:46 AM

or IC, why would it climb again significantly after 6500? I know I'm probably overlooking something basic, but I'm sorta tired and distracted at the moment.

Mike2kS4 · 08-20-2004, 11:47 AM

PSmalls::DoggieStyle · 08-20-2004, 11:48 AM

Funkweasel · 08-20-2004, 11:51 AM

Mike2kS4 · 08-20-2004, 11:54 AM

Mike2kS4 · 08-20-2004, 11:56 AM

08-20-2004, 11:33 AM	#1
Mike2kS4 Elder Member Account #: 38083 Join Date: Jun 2002 Posts: 12,104	Stage 3 Homebrew fueling UPDATE. Airbox mod and new Lemmisettings: (BWW) Check out the below link for my initial post regarding my homebrew fueling for my K16/K04 Hybrids. I figured that I may be getting higher MAF readings because the OE airbox has a bottleneck of about 3.25" between the MAF and the filter element. I ran a 3 5/8 holesaw from where the MAF meets the airbox down to the chamber of the airbox. This removed about 200 degrees of the circumference of the airbox outlet. Using blue painters tape, I formed a smooth transition between the MAF hole and the airbox chamber and covered it with JB weld. I then painted it black. To my surprise, this mod made a significant difference, lowering my g/s by about 7% throughout the rev range. I had to richen the mixture commensurately. Top view of the JB welded portion, the O-ring is insurance against the clips popping open. This setup has NO SCREEN. View from the side. Up close it looks like crap, but with the hood open it's not obvious at all. As this picture shows Above are my new 'winks settings, used to compensate for the lower MAF readings. Again, YMMV on these settings. I lowered the timing from my previous settings because of heat soak and 95 deg ambient lately. Logs of my MAF and Timing. Excuse the sparse data points. I was also logging O2 values and adaptation. .875 and bouncing above and below 0 at cruise and idle Key note: My MAF peak now reads 20 g/s LOWER. Which gives me plenty of resolution for high-boost work! http://forums.audiworld.com/s4/msgs/1736997.phtml __________________ 2002 S4 Avant, 6spd. Bone stock. <a href="http://www.autospeed.us"> </a> Caveat: Any advice I express regarding potential tuning and such is purely informational. If your knowledge and abilities are not up to the task, no amount of advice can assist.

08-20-2004, 11:37 AM	#2
Funkweasel AudiWorld Super User Account #: 28517 Join Date: Nov 2001 Posts: 10,137	What's with the g/s "dead band" b/w 5800 and 6500rpm? Think its a weird flow effect of the new airbox connection or something else?

08-20-2004, 11:40 AM	#3
Mike2kS4 Elder Member Account #: 38083 Join Date: Jun 2002 Posts: 12,104	*All of my logs are similar to that, My ported wastegates are very* effective once peak is met.** And my restrictive IC's even make their job easier. __________________ 2002 S4 Avant, 6spd. Bone stock. <a href="http://www.autospeed.us"> </a> Caveat: Any advice I express regarding potential tuning and such is purely informational. If your knowledge and abilities are not up to the task, no amount of advice can assist.

08-20-2004, 11:45 AM	#4
Mike2kS4 Elder Member Account #: 38083 Join Date: Jun 2002 Posts: 12,104	Though it is flatter than the others, slightly. The scale I chose for the chart exaggerates it. The rising g/s slope isn't really that drastic if you look at where the data points start and end. __________________ 2002 S4 Avant, 6spd. Bone stock. <a href="http://www.autospeed.us"> </a> Caveat: Any advice I express regarding potential tuning and such is purely informational. If your knowledge and abilities are not up to the task, no amount of advice can assist.

08-20-2004, 11:46 AM	#5
Funkweasel AudiWorld Super User Account #: 28517 Join Date: Nov 2001 Posts: 10,137	Hmm, but your previous post didn't show that. And if it was a wastegate issue or IC, why would it climb again significantly after 6500? I know I'm probably overlooking something basic, but I'm sorta tired and distracted at the moment.

08-20-2004, 11:47 AM	#6
Mike2kS4 Elder Member Account #: 38083 Join Date: Jun 2002 Posts: 12,104	The slopes correlate well. I'm convinced there isn't a problem there, other than my IC's ;) __________________ 2002 S4 Avant, 6spd. Bone stock. <a href="http://www.autospeed.us"> </a> Caveat: Any advice I express regarding potential tuning and such is purely informational. If your knowledge and abilities are not up to the task, no amount of advice can assist.

08-20-2004, 11:48 AM	#7
PSmalls::DoggieStyle Elder Member Account #: 69223 Join Date: Jan 2004 Posts: 30,258	*Nice, now I don't have to btch at you for needing more headroom ;-)**

08-20-2004, 11:51 AM	#8
Funkweasel AudiWorld Super User Account #: 28517 Join Date: Nov 2001 Posts: 10,137	I don't doubt it, just curious about why it behaves that way. Its the geek in me.

08-20-2004, 11:54 AM	#9
Mike2kS4 Elder Member Account #: 38083 Join Date: Jun 2002 Posts: 12,104	Posting another log, made 5 seconds later. All is good ;) __________________ 2002 S4 Avant, 6spd. Bone stock. <a href="http://www.autospeed.us"> </a> Caveat: Any advice I express regarding potential tuning and such is purely informational. If your knowledge and abilities are not up to the task, no amount of advice can assist.

08-20-2004, 11:56 AM	#10
Mike2kS4 Elder Member Account #: 38083 Join Date: Jun 2002 Posts: 12,104	Yea.. nothing worse than a b!tchy midget ;p __________________ 2002 S4 Avant, 6spd. Bone stock. <a href="http://www.autospeed.us"> </a> Caveat: Any advice I express regarding potential tuning and such is purely informational. If your knowledge and abilities are not up to the task, no amount of advice can assist.

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