02BlkZ28

Kay guys help would be appreciated. Took my car to dyno & the tuner told my to yank off that after market MAF sensor & put the stock back on or he wont guarantee the tune. Said that after market MAF sensors make your car run lean! So is he dumb dumb or what lol?? & also if that is true his do i get rid of the sensor all together. Cause that thing looks like it restricts air flow big time!!

infinitebird

iTrader: (11)

Nope, he's right. Replacing the stock MAF is one of the worst mods you can do. Unless you have a serious FI setup and are pushing 600-700hp don't even think about touching the MAF.

It's not a restriction until way more than stockish power levels. Even then, it's better to descreen the stock one than replace it.

MadFirehawk86

iTrader: (2)

A stock MAF will not restrict airflow not in the slightest...and do not remove that screen either. The screen creates linear air flow across the sensor and DOES NOT restrict air flow.

+1 on the HP bit too...a larger than stock MAF is not needed unless you have a serious big cube/unstreetable setup and even then most builders convert over to speed density at those power levels.

poltergeist 02

iTrader: (65)

You could always use an 85mm gm maf.

sepsis

iTrader: (7)

Or you can keep your stock MAF, de-screen it, and use a Saxon honeycomb screen.

dr_whigham

iTrader: (49)

My tuner told me the same thing, and he knows his ****.

Having said that, I was pulling vacuum at WOT at 452rwhp, so I went speed density. Getting that restriction out of the intake tract netted me another 8/6 to the tires. Obviously no additional tuning after yanking the MAF; everything was already dialed in.

Just removing the MAF itself netted those gains. And that wasn't some high cube / unstreetable build. At all.

02BlkZ28

Im putting down 473 to the wheels & i got no vacuum at WOT. I got a vacuum gauge on here. Just making sure im not leaving power on the table. What i gotta do to lose my MAF sensor & go to speed density??

infinitebird

iTrader: (11)

Still requires alternate tuning, so his tuner would need to make the appropriate adjustments. Those files are readily available though.

ramairetransam

iTrader: (18)

your tuner is right . I have a gm 85 mm maf with about 1000 miles on it if that and the receipt from when i got it and how much i paid . I went speed density tuned since im procharged now making about 10 lbs .

Go with a gm maf or dont run one . The slp and granatelli are ****.

dr_whigham

iTrader: (49)

Have your tuner just put it in closed loop speed density. If everything is already dialed in there's nothing to do. It literally takes 15 seconds.

What intake are you running? I was at 96kPa at WOT. Ditched the MAF, made another pull, and it stayed at 100.

HioSSilver

iTrader: (8)

I've always descreened and ported the maf. The SLP 85mm on my car now is descreened and ported. It runs fines. I'm about to go to a 100mm and a ls3 style cartridge maf. I see no purpose in have a 90-102 tb with a restrictor in front of it.

02BlkZ28

I had a Super Vic but im going back with the FAST 102mm setup.

MMWS6

SLP is a GM MAF with a resistor on it. Keep airflow straighteners in any MAF you run. Turbulence at idle is not worth the tiny bit of airflow gains. Now, take an LS2 for example, moving that engine to a card style MAF and an airflow straightener and it will net as much as 25hp on a dyno with no other changes. GM MAfs are the best and I would not use anything but. Do not use Delco MAFs as they are usually rebuilt and fail constantly... they are crap. I've seen multiple fail right out of the box and when I was with GM most of my mechanics refused to use them because they caused too many comebacks and it was a strike against them for something they had no control over! Spend the money and get OE. If you think that your MAF is restricting then move to a card style in a 100mm tube. Straightener of your choice in the front, screen after the sensor and you can feed just about anything with it, anything.

DANOZ28

iTrader: (1)

could someone please explain how a stock 78mm maf sensor can move a sufficient volume of air to feed a fast 90 or bigger? arent engines just giant air pumps?

HioSSilver

iTrader: (8)

Why have the starightener in front of the card style??????? The card style has nothing in front of them in oe form.

soundengineer

iTrader: (16)

you need a different tuner....
any MAF can be tuned fairly easily

that tuner is either Lazy, or doesnt know how to tune, or a combo of both.

tell him to **** off and then go find a better tuner.
you can rent dyno time from him without him being the tuner...just dont use him to tune.

dr_whigham

iTrader: (49)

I don't think it's a question of tuning. Geoff and I had this same conversation. The card MAF's are simply erratic in reading unless it's WOT.

The screen is a good idea though as it smooths the airflow. Even Haltech includes it in their CAI's.

soundengineer

iTrader: (16)

thats funny, cause new GM vehicles use a Card style MAF...from the factory.

The Card MAF is not the issue....
its the Tuner not knowing how to make it work...
you cant just adjust the MAF table alone when you switch from a Wire MAF to a card MAF...
theres an entire page of other variables that you have to change.

PuruJones

great question, i'm a similar boat, I'm a I'm have a descent cam and fast 92/90 and supporting mods. i'm at the point, where anything above 125shot, I don't get anymore airflow. an im trying to find the bottle neck in my setup.

soundengineer

iTrader: (16)

you can get an increase in velocity by having a small reduction in size just before the intake.....is it really enough to make a difference....probably not...usually more power increase if you just upsize it

and a 125 shot doesnt supply more airflow(I'm sure that is not what you meant, but the way you have it worded is that your Nitrous is increasing your airflow...and that is not how it works.)

if you cant make more power with a bigger shot, you issue is likely in the heads themselves or your cam choice (big shots of nitrous need Big splits with Large Exhaust durations)

plenty of people making a lot bigger shot happen with a stock MAF (I have a buddy who did a 250 shot with the stock MAF/TB/intake)