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Discussion Starter · #1 ·

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I think I remember Mike K having some issues with it it on his Z.

I have tried running my car with no filter (I put a mesh screen over it to keep out large stuff. I did one quick run, got the same max MAF voltage, and put my filter back on. Another thing. With the AEM intake, the filter is exposed to direct air via the opening in the bottom right hand side of the bumper. There is no exit for the air either, because the plastic fender lining blocks it.
 

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mpg9999 said:
I think I remember Mike K having some issues with it it on his Z.
Yeah, the turbulence was causing crazy/inconsistent MAF readings if I remember correctly. The MAF uses a "hot wire" to effectively measure the mass of air. Basically, it tries to keep the wire at a constant temp. The more air/mass of air that flows over the wire, the more voltage/power that the wire needs to stay at the constant temp.

Anywayz, think of it like a nice flowing river vs. a class 5 white water rapid. All that turbulence will probably cause some crazy readings from the hot wire. That's my guess at least.
 

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Most of those MAFs hang the hot wire into the air stream, I think turbulent air would effect those more. That being said, the first cone filter adapter I ever put on my car, way back in '96 didn't fit exactly right.(overhung the sample tube by about 1/8 inch) The car would start up just fine, but as soon as you stepped on the gas, the car would stall. My buddy was there with his SE-R, so we swapped my MAF to his car.(without adapter) His car ran and revved fine. We figured it was just a bad connection the first time, and reinstalled the MAF,adapter and filter. Started fine and stalled when revved. We started the car without the adapter on and it revved fine. I got my friend to place the adapter over the MAF while it was revved up, it immediately started to run rough and then stalled out. That right there tells me that even a small amount of change in airflow in the sample tube will cause problems. Also if you look inside the stock airbox lid, it has a small lipped velocity stack to smooth air intake in to the MAF. I don't know if the screen will help our MAFs as they weren't originally designed with one, versus the some of the other MAFs out there. (Chevy,Mitsu etc.) Keep us posted.

Travis E.
 

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Discussion Starter · #7 ·
OK, did a lil soemthin somethin today, I made a semi closed box around the air filter effectively blocking incoming turbulant air from the front of the car and the radiator fans, here r some observations I noted.

1) On coast down my o2 voltage will quickly get to .00-.01 volts everytime without a doubt even at 100mph+ so no turbulence is hitting the filter screwing up MAF volatge.

*Before my car on coast down would normally only see .07 - .15 volts during coast down (lifted throttle) and take longer to get there. Also now there seems to be a strange sense of smoothness about how the power is put down.

**I think thios is also going to improve gas milage, that wastegate gass on coast down cuzz injectors should be shut down.
 

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Discussion Starter · #8 ·
So if anything by keeping the air filter in a stale enviornment just like it was when it was stock, u will have more accurate readings of the mass of air that is entireing ur engine...........also did u know it also ****s with ur a/f ratio, special at high speeds for me as noted by my o2 volatge via my Apex TT
 

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Discussion Starter · #10 ·
My o2 is just really consistant know on decel..........

**BY OPEN AIR FILTER I DONT MEAN WITHOUT AIR FILTER, I MEAN OPEN TO OUTSIDE TURBULENCE
 

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You should post some pics of your new filter set up, i would like to see what you have done to it. I think everyone should read all of the links/threads you have posted, there is alot of interesting info and points that people bring up. Have you put a screen on you maf yet?

later,Jon
 

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Discussion Starter · #13 ·
civicdragon said:
so where is the maf located in a bb car? and how far from the maf is the air filter element? Anyone got engine bay pictures of BB's?
Its doesn;t matter where it is located, what matters is that no turbulence interfere with the inducted air............as far as MAF and filter distance apart it is the same as the DE.
 

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Thats good info. I remember having a high speed problem sometimes with my SE-R. It seemed to fall asleep a bit sometimes and I wondered if that was partially to blame. When it comes out of storage next month I will conduct a test with my nProbe.
 

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Good info here. Charlie--I think you may have solved my lean condition--after last winter's upgrades(front mount cooler/different intake setup), I have had my lean problem, no matter how high I adjust the fuel pressure, and had tested everything. I realized that I had installed a $15 intake adapter and filter off e-bay that may not be allowing the air to flow through the "Sample stream". I'm stoked about this--I'm going to re-install my POP-charger tonight and drive it and see if I notice anything. And later I will make use of my sheet metal bender I bought for $80 and never used to make a turbu-NOT box.! !! HA HA!
 

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Ok, I checked tonight. My o2 voltage goes straight to zero. I tested from 80 mph. All the way to 40. It always shots straight done to zero volts as soon as I let off the gas. My filter is exposed directly to outside air.

-Mike
 

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Discussion Starter · #17 ·
OK one more thing when i first did my swap my filter used to sit under the battery tray exposed to alot of outside air when it was like this i had trouble getting my o2 voltage above .88volts no matter what i did to the SAFC and it would hit a stall point at high speed where it didn;t want to go any faster..........then I installed the splash guards that go under the radiator just so happened my air filter just about rested on top of it........after putting the splash guards on I noticed a huge difference in the top end performance and my o2 voltage hit .94 volts.......and the car steady climbed to 130mph+ with no problem
 

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Well, I re-installed my POP-charger and drove it--it is definitely better, but not completely fixed--it still dips into the .85-.90 regularly--at both 8, and 11psi; I tried both.
These are all very viable ideas here--since most hard accel occurs between 70 and 110, where there is A LOT of wind pressure, and turbulence.
SPLASH GUARDS---Yet ANOTHER great tip from Charlie. I took mine off when I got the car cause I work on it so much they get annoying, but I will try that and see if I can STAY in the .95V range.
 
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