Removing MAF screen????
#82
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</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by StealthStalkerLS1:
<strong> You guys pulling your screens be sure to let us know how it went!.
<img border="0" title="" alt="[Big Grin]" src="gr_grin.gif" /> </strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">I took my screen out, no problems so far. <img border="0" title="" alt="[Wink]" src="gr_images/icons/wink.gif" /> Thanks for all the replies! <img border="0" title="" alt="[Big Grin]" src="gr_grin.gif" />
<strong> You guys pulling your screens be sure to let us know how it went!.
<img border="0" title="" alt="[Big Grin]" src="gr_grin.gif" /> </strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">I took my screen out, no problems so far. <img border="0" title="" alt="[Wink]" src="gr_images/icons/wink.gif" /> Thanks for all the replies! <img border="0" title="" alt="[Big Grin]" src="gr_grin.gif" />
#84
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</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by camaro_ls1:
<strong> Any pinging over 5,000rpms? </strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">I have not heard anything unusual. Was the pinging you heard quite noticeable or was it somewhat quiet? The exhaust is prett loud, and hearing things at 5k tends to be a little difficult. I had pinging in my previous car, 99 Cobra, and that I heard over the exhaust, but it ended up being a very bad situation <img border="0" title="" alt="[Mad]" src="gr_images/icons/mad.gif" />
<strong> Any pinging over 5,000rpms? </strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">I have not heard anything unusual. Was the pinging you heard quite noticeable or was it somewhat quiet? The exhaust is prett loud, and hearing things at 5k tends to be a little difficult. I had pinging in my previous car, 99 Cobra, and that I heard over the exhaust, but it ended up being a very bad situation <img border="0" title="" alt="[Mad]" src="gr_images/icons/mad.gif" />
#85
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The pinging I had over 5K rpms wasn't related to removing the MAF screen. It was very noticeable even with the exhaust and my stereo going. You shouldn't get any pinging with the !MAF.
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The Only reason I blamed my pinging above 5k RPM's on my Maf Screen was because someone on another site told me to try flipping the MAF around backwards (so that the flow arrow was pointing the opposite direction). As soon as I did that the pinging was gone so basically it confirmed I was running a little lean. I just assumed since the only thing I did to the MAF was remove the screen that it was responsible for my problems.
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Here's another thought.. Perhaps we addressed this already but anyhow.. I think we all agree that during Part Throttle (Normal Driving) one of the things the PCM will monitor is the o2's to determine proper A/F ratio. Any deviation from that and the PCM will make a short term correction. If the PCM notices it's making pretty much the same short term correction over and over it will make a Long Term Correction. Eventually WOT comes into play and we know that the PCM does not look at the O2 Data when you go WOT but the Fuel Tables for WOT were built during the Normal Driving so.. Basically the PCM is just too smart so I ask.. Why is a device like MAFT ever needed in the first place?
A common problem with LongTubes if I'm not mistaken is a very rich condition.. Why doesn't the PCM just fix itself in this situation?
A common problem with LongTubes if I'm not mistaken is a very rich condition.. Why doesn't the PCM just fix itself in this situation?
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</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by StealthStalkerLS1:
<strong>
A common problem with LongTubes if I'm not mistaken is a very rich condition.. Why doesn't the PCM just fix itself in this situation? </strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">What makes you think the PCM will not fix this problem? I think the only thing common here is that people get discouraged too soon and buy a MAFT to fix this problem. I have SLP LT's, no cats, and 3.5 inch all the way back. I also have FIPK. When I drove the car for the first time after exhaust I had about -12% LTFT's. I have put about 3000 miles on the car and I am down to -4% LTFT's with no MAFT or other tuning for AFR when cruising around about 1400 RPM. You gotta drive a pig rich car for awhile <img border="0" title="" alt="[Wink]" src="gr_images/icons/wink.gif" />
However, (IMHO)the PCM can only keep up with so many mods. the MAFT is neccessary when you get to messing with injectors, MAF and TB porting and anything else that makes the stock programming confused or inaccurate.
<strong>
A common problem with LongTubes if I'm not mistaken is a very rich condition.. Why doesn't the PCM just fix itself in this situation? </strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">What makes you think the PCM will not fix this problem? I think the only thing common here is that people get discouraged too soon and buy a MAFT to fix this problem. I have SLP LT's, no cats, and 3.5 inch all the way back. I also have FIPK. When I drove the car for the first time after exhaust I had about -12% LTFT's. I have put about 3000 miles on the car and I am down to -4% LTFT's with no MAFT or other tuning for AFR when cruising around about 1400 RPM. You gotta drive a pig rich car for awhile <img border="0" title="" alt="[Wink]" src="gr_images/icons/wink.gif" />
However, (IMHO)the PCM can only keep up with so many mods. the MAFT is neccessary when you get to messing with injectors, MAF and TB porting and anything else that makes the stock programming confused or inaccurate.
#89
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I installed QTP LTs not long back to my '02 Z. No fuel/air adjustments were made. My O2s average about .910mv now which is about where it was before. I ran 11.82@113 MPH last weekend internally stock, with stock gears, and with only the spare and jack removed. Seems the PCM adjusted well enough for me. <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" /> I'd like to get it on a wideband one day to make sure though.
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</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by SSLink:
<strong> Just one last thought. Air being forced through the openings in a screen could be moving at a slightly higher velocity than the same amount of air flowing through an open orifice, although I have no proof of this (any physics majors out there?). </strong></font></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">The colonel is about right. Removing the screen will barely affect flow amount. It will barely effect flow velocity. Porting will slow velocity and barely affect flow amount. I believe I hear somewhere the MAF flows 805CFM (think about your carbuerator days). The funny thing is, that is plenty of air considering your TB flows maybe 850cfm and so does the LS1 intake. I would leave the porting alone until you have passed 450HP or so, then port the intake pieces (MAF, TB, Intake) and use your MAFT to correct any wild A/F ratios in part throttle or WOT.
The tough question here, is how do you get 805CFM of air available to your MAF? That's hard to do without a great ram air set-up, large filter area, and high vehicle speed. It takes a lot to top it out. You shouldn't need a bigger MAF or TB until you have (I believe someone mentioned before, this word...) DEMAND for that much at the mouth of the MAF. At that point, you also need to compensate with injectors that can keep up. Forced induction (Turbo,SuperC) cars really have to think about this air flow amount and computer/injector tuning.
I have a de-screened MAF and A4, works fine!
Sincerely, Physics Major UNF
<strong> Just one last thought. Air being forced through the openings in a screen could be moving at a slightly higher velocity than the same amount of air flowing through an open orifice, although I have no proof of this (any physics majors out there?). </strong></font></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">The colonel is about right. Removing the screen will barely affect flow amount. It will barely effect flow velocity. Porting will slow velocity and barely affect flow amount. I believe I hear somewhere the MAF flows 805CFM (think about your carbuerator days). The funny thing is, that is plenty of air considering your TB flows maybe 850cfm and so does the LS1 intake. I would leave the porting alone until you have passed 450HP or so, then port the intake pieces (MAF, TB, Intake) and use your MAFT to correct any wild A/F ratios in part throttle or WOT.
The tough question here, is how do you get 805CFM of air available to your MAF? That's hard to do without a great ram air set-up, large filter area, and high vehicle speed. It takes a lot to top it out. You shouldn't need a bigger MAF or TB until you have (I believe someone mentioned before, this word...) DEMAND for that much at the mouth of the MAF. At that point, you also need to compensate with injectors that can keep up. Forced induction (Turbo,SuperC) cars really have to think about this air flow amount and computer/injector tuning.
I have a de-screened MAF and A4, works fine!
Sincerely, Physics Major UNF
Hello all. New to the forum. I have a Vortex 6000 in a 2500HD and was searching web for simple mods and came across this post.
To simplify things a little. The MAF unit has both air velocity sensors and a temperature sensor diode in it to measure both. Removing the screen does not harm much. Tell me this, what happens when the intake filter is getting plugged and the airflow is reduced? The MAF picks up the drop in flow and volume and corrects the AF accordingly. This is done to help correct the rich mixture and poor economy found in older engines with carborators and some TBI. The air flow slows down but the fuel is jetted the same without correction so economy drops. Don't get too heady about it. Yes, the screen both protects and helps straiten airflow but is not an absolute major component. Increasing airflow is similar to installing a new filter. The PCM will adjust accordingly.
Thanks.
#91
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13 year old post.. But what's the general consensus now a day about the MAF screen? In 03 I'm sure most of these cars didn't run to many miles with the screen off, and everywhere I've been no matter what engine I have has always had mixed feelings about it.
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My penny's worth - if you have a nice long, straight intake before and after the MAF where you're basically getting laminar flow, no screen needed. If you have a 4th gen f body intake which is really short and has a few bends near the MAF, the screen is helpful