The infamous "lean" dicussion with tuners and intakes

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  #31  
Old 01-23-2009 | 02:45 PM
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From: Among javelinas and scorpions in Zoniestan
Originally Posted by ronburgundy
carbs are for quitters.
Now, now - you haven't really had fun until you've tried to get a tri-carb setup adjusted right.

- Jack
 
  #32  
Old 01-23-2009 | 02:58 PM
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Originally Posted by JackandJanet
Now, now - you haven't really had fun until you've tried to get a tri-carb setup adjusted right.

- Jack
Two mechanical Holley four barrels on a 427 were a snap.
 
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  #33  
Old 01-23-2009 | 03:01 PM
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Originally Posted by JackandJanet
Thanks, I knew increasing WOT would not be ideal at all, but thought it might help until a custom fuel map could be generated. The reference to fuel trims is actually on Pg 70 and 71 in s1.pdf, but as I understand it, the PCM tries to keep the air/fuel ratio cycling around an ideal point based on what the O2 sensors see and report to generate the STFT pulses to the injectors. Yet, because people report symptoms of running lean (white, worn plugs, etc.) the PCM must not be able to do it if the baseline settings are too far out of whack and the LTFT values have reached a limit that prevents compensation for the larger deviations.

Or am I missing something here? (Wouldn't be the first time). :o Carburetors were certainly simpler.

- Jack
Adobe page numbers silly, not 1-70 & 1-71.

As for the plugs, a stoich ratio seems normal for 'white' plugs. Now if we were constantly running O/L @ 12.5AFR, you wouldn't see that.
 
  #34  
Old 01-23-2009 | 11:35 PM
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From: Among javelinas and scorpions in Zoniestan
Originally Posted by Bluejay
Two mechanical Holley four barrels on a 427 were a snap.
Right! (You MAY have me here).

- Jack
 
  #35  
Old 01-25-2009 | 05:06 AM
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what is the web site for PHP ?
 
  #36  
Old 01-25-2009 | 08:42 AM
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Originally Posted by gregk63
what is the web site for PHP ?
http://dygytalworld.ehost-services139.com/php/
 
  #37  
Old 01-27-2009 | 11:42 PM
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2004 or 2009?

Originally Posted by ASEMechanic
I can see we are going to go 'round & 'round on this issue. Hopefully this will settle the debate. Maybe it won't... who knows?

This dyno plot was made on a 2004 F150, both before and after installing an AFE CAI kit. The runs were about 50 minutes apart, which was the time it took me to install the CAI. All test conditions were the same and the engine was at full operating temperature (both ECT and EOT) when making both runs. Take it for what it's worth.

(click for larger image)


Unfortunately, the sampling software didn't correctly log the AFR from the meter but fortunately we did make a note of the AFR for each WOT run because as soon as I saw the results, I was on the phone with AFE.

Stock w/o CAI- 14.4 AFR (+/- .1)
Stock w/AFE - 15.6 AFR (+/- .1)

When I contacted AFE about this issue, I was basically told I didn't know what I was doing and I was supposed to have let the PCM "relearn" the fuel curves. Now I didn't necessarily disagree with this so after running about an hour on the dyno at varying speeds, loads, and throttle positions, I did a few more runs with exactly the same results. What's even funnier is that when I put the stock airbox back on, my power curve and AFRs returned to normal... WIHTOUT having to relearn any fuel maps.

I will say that after correcting the fueling and MAF tables to compensate for the airflow offset cause by the CAI, the truck picked up about 8 HP above 3000 RPM. Oddly, it's nearly the same 8 HP we picked up at the same RPM by removing the snorkel from the fender. Go figure. Oh, and the stock airbox didn't DRONE!

Again, take it for what it's worth. In my opinion, the stock airbox on the F150 provides more than enough flow, at least for a naturally aspirated application. Supercharged or other Forced Induction applications will certainly be different and airflow requirements are dramatically changed in these applications.

Hope this helps.
At the bottom of your chart it says 2009 f-150. Is that a typo?
 
  #38  
Old 01-27-2009 | 11:44 PM
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Originally Posted by skyhikr
At the bottom of your chart it says 2009 f-150. Is that a typo?
No, it was a 2009 5.4
 
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  #39  
Old 01-27-2009 | 11:52 PM
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Thanks.

Originally Posted by Bluejay
No, it was a 2009 5.4
In the text of his post he said it was for an 04.
 
  #40  
Old 01-28-2009 | 12:01 AM
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Originally Posted by skyhikr
In the text of his post he said it was for an 04.
I see what you mean now. I know he just recently dynoed a 2009. I suspect the 2004 is incorrect. Maybe he will see this and clarify.
 
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  #41  
Old 01-28-2009 | 03:39 AM
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Even with all this talk about a/f a dyno chart is a dyno chart so when K&N posts up numbers that shows the increased HP that's good enough for me. Now my dad's C6 probably doesn't need an aftermarket intake but a C6 was actually made for HP and regular F150's weren't so yeah I'm not surprised if Ford did some sneaky things to help the life of the truck vs HP/TQ #'s but hey it's not a race truck. BTW maybe it's this Afghanistan internet but I'm having a hard time getting to the PHP site(s).
 



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