Well my mods are in my sig... I have a custome CAI, i relocated my battery made a hole in the area where the batter use to sit and the filter SITS right behind my driver fog light. ANYWAYS... I built a CUSTOM 3'' MAF, SS with a flange and all, threw it on , and the cars idle was a bit rough to begin with... i drove thecar about 200 miles and now its fine.

Ok the cars throttle response is SOOO much better, just tapping on the gas the car launches forward ! HIGH END is CRAZY ! the cars runnign SOOO much better, it pulls like crazy up top, im able to break tires after 4.5k in 2nd when i smash it.

1 thing i noticed is that my exhasut is POPING alot more, it has the cracking sound from it everytime i let off.

 

Using a larger MAF housing without adjusting the AFR.

 

Not data no care.

 

might be spitting fire. When my car ran pig rich with no cat, I'd spit flames occasionally. Yours might be running rich due to lack of a/f adjustment?

 

yup my car does the same thing, I have to get tuned badly or at least a generic jwt ecu wit advanced timing. You might wanna make sure that filter is protected cuz I heard of someones engine hydrolocking earlier this week from water in the cold air intake, I am just gonna keep my short ram stillen intake.

 

Sigh.


Larger MAF housings make the AFR more lean due to the reduced velocity of the air passing over the hot wire.

 

"I installed a larger MAF without reading or ignoring the countless posts that told me I am supposed to re-tune my AFR. But hey, they're only pistons."
1. NiSmOVQ35
2.






I expect this list to grow quickly.

 

How do yo know i didnt do my research ?
Do you know my plans ? what im ganan do next etc ?
NO.

THe guy whose going to be tunning my car has a nice little list of people ahead of him, currently im putting on all my bolt ons b4 i get it tunned. Im not worried about blowing my motor, cuz its in the body shop till vinney ten is ready to tune my car.

i just wanted to share how it felt after the 3' MAF, my car HAS been runnign EXTREMELY RICH, being able to tell via my aem ugeo, now WITH the 3' maf YES it has less rich but not to lean.. where as my pistons would go.

Thank you.. have a nice day

 

The fact that you made no mention of AFR led us to question whether or not you understood the potential danger. Good to hear that you do.

 

vinny ten is the man, good luck w/ the tune man

 

wow, a 3-foot MAF? that's sick!

btw, it's "tuned," not "tunned."

 

sorry my grammer wasnt up to your standards .. and you had to be mr. wise ***? what are you a english teacher ?

 

I'll say whatever I feel like saying. Deal with it.

Just thought you might want to know the correct spelling since it's in your sig....

 

irish44j.. i changed it just for you hun . LOL

 

thanks sweetie

 

Do you ever plan on getting us any data to back said claims? I.e., dyno/AFR/tune ET's?

 

 

More so without data.

 

Yes, some data would be nice

 

pimpin02max please stop trolling/post whoring. If you have nothing useful to add or legitimate questions to ask please refrain from posting in this thread.

 

no guys sorry i dont have data, the only bit of info i can share is the car went from runnign PIG rich to Less pig rich it went toward being a lil lean but nothing major, i examined that from my aem wideband. I will dyno the car soon, but i wont be able to tell you what the 3" maf did for me on paper since i have many mods i havent dynoed.

lemme get a pic this week and throw it up =), this will also show my custom intake.

 

So then you do have data? I'm not very familiar with that WB, so is it possible to export some data from it (AEM wb)? If so, care to post the graphs in an attempt to make this thread semi useful/informative. Not like we don't know nor that we don't believe you, but it would be another comparison. Also, what do you mean by pig rich? Numbers would be nice. Also, exact specs on your current MAF set-up would be nice, i.e., location in intake tract and exact I.D.

Never a good thing for comparisons, but all too common around here. I am in the same boat as the only base run that I have is headers and everything else completely stock. That and my dyno wasn't the most informative since I pretty much didn't know much about dynoing an auto.

 

Why would your car be running so rich in the 1st place? Common VQ35 trait?

 

For stock software'd A33B's, yes it is. I've never seen an 04 A34 AFR, so I cannot comment about those. But on the Altima forum, it seems as if they're about 12.5 ish with the addition of stock WB's (05+). I would imagine it's the same for 05+ A34's.

 

i think its common because most people want to jump in a start doing everything they can. makes sense really. thats why i dont have one. then once its decided that someone wants to test a part for proof of gains, its too late. oh well though. i would like to be able to show the gain of any part i can think of, but i know it wont be until the next thing I try

 

hey whats up guys....
for some reason no matter how much fuel i take out from my SAFC, my wideband shows similar readings, and currently im running more towards the rich side. (12.8-13.1)
So im thinking, with this larger MAF 3", will this correct a bit better? since im guessing larger MAF, more air, run more lean, and maybe it'll put me on the 13's on my A/F...? Correct me if im wrong.

 

Exactly ho much are you taking out (%)? Also, are these numbers (12.8-13.1) when WOT?




You're making out to seem as if the ECU cannot compensate fast enough. But this is what's REALLY happening.

Post # 6 of this very thread

 

Yes, those readings are showing under WOT....
i was taking out about for instance 14% before and reading 12.8 so i have decided to take out about 16%-17% and it still reads the same.

 

Does it still do that thing that once you go above -"X"% correction the a/f all of a sudden jumps from ~13.1 to mid 14s?

 

it does that sometimes.... i actually noticed one thing today is when i was at high rpms, my a/f read super lean like 18's for a split second then dropped to 12.8ish when i was on WOT.

but my main concern is that it feels like my SAFC is not able to take out anymore fuel, no matter how much % i take off, ill still be running at around 12.8-13.1 or so. i've tried taking out as much as 22% before, but no change either.... its very hard for me to get my a/f to read at a steady 13.5. i also dont want to overdo it, because im afraid that it might catch on and cause my car to go superlean and mess something up.

 

I would 1st think that what if its the wideband itself giving a faulty reading... but thena gain you tell me that when the a/f fluctuates like that there's a noticeable change in the pull (hard, then brickwall, then hard when it goes back to normal), so thats not it.

SAFC should be more than enough to take out up to 50% fuel, so thats not it. There's something else going on... that something else is whats been bugging you for months now, lol. Just like my ignition timing

 

Where's the wb located in the exhaust stream?

 

I would like to see a pic of a 3inch maf or better yet a custom 3inch maf

 

http://forums.maxima.org/showthread.php?t=517758&page=3
Post #76 and down

Right now its got a coat of silver paint, and a filter on it

 

ok I got ya im wondering how well it would work with a z32 Maf. I would use some 3ich steel pipe and fit the sensor into it. How would it affect timing?
Also im boosted with 555cc injectors what would be the gains for me doing this and would thier be any power increase?

 

Ok the way I understand this theory... lets use stock ECU (no SAFC) as an example...

- 70mm MAF (A32) reads say 78.9% airflow on my 3.5, this exerts theoretical load value X to curve ignition timing in a certain way

- 75mm custom MAF (my rig, lol) reads 58.6% airflow, this exerts a LESSER theoretical load value than X, and thus curves ign timing to allow for more timing

In your case being boosted, thats a bad thing obviously. However, (and excuse me for not knowing if you have said so before, must have missed it) if you have an SAFC/ E-Manage, you can select the MAF to be read, so instead of using the A32 MAF input curve, you can use the Z32 input MAF curve (that MAF is 75mm ID, and a 3" ID pipe= 76.5mm, close enough) so that it should not affect your timing to a noticeable degree, because the ECU will think it has the right MAF.

I know I wrote it a bit confusing at the end there, lol. I understand my geberish, I just hope you guys can make sense of it,

 

Yes Im using a eu. But I guess with it only being a 1.5mm differance I wont see any power gains. Correct me if Im wrong

 

Oh yes you will, from the share improvement in airflow by itself. Im not sure how evident it would be under boosted conditions, but from my buttdyno (and real dyno) I got 10whp at redline from this, and better respsonse.

Keep in mind the ID of the intake tubing, with me it used to be...

3" cone> 70mm MAF (2.75ish)> 3"midpipe> 3" (75mm) TB OPENING (happy NMexMax? )

The MAF itself acts like a restrictor in a way, so when you do a 3" MAF, it keeps the ID of the intake piping at 3". I cant even guess as to what #s it would yield on a boosted applications, but im sure the response improvement is going to be noticeable throughout the powerband.

Its evident to me daily driving, WOT its obvious on the top end. You boosted probably flow as much air at X partial throttle as I do at WOT, so I'd only assume that your gains would be ubber, but only dyno will tell.

 

Yeah but remember im only going up 1.5mm in size! Do you think their would be a 5whp increse for me?

 

ah crap sorry, you already have a Z32 MAF . In that case i doubt the 1.5mm gain would be worth anything really, blah.