Ramairbird

iTrader: (17)

I posted a similar post in the gen lV forums but this one has more traffic. My mods are in my sig. I'm wondering if the stock maf and whisper lid are a significant restriction for my 376 ls3. The TB is a 90mm. I don't want to spend big money to upgrade to an 85mm lid and maf if the gains are going to be minimal. The cam is a 231-243 113+3. I've done a search on mafs but I can't find anything definite. Thanks.

oberth1

iTrader: (6)

I was wondering that too. Seems like a waste to be using a 85mm intake, 80mm TB and then a 70 -somethin Mass air.

fbodyman1026

iTrader: (11)

I remember hearing they are good up to like 500 at the crank. The you might be leaving some on the table. But yes, I do think it is pointless to buy a bigger lid (85mm) if your going to keep the stock maf.

2001SS_stompinsupras

GMHTP tested one and hp gains are minimal, but bigger is better. u dont have to change lids though, just run a bigger maf

hitmanws6

iTrader: (20)

unless you need to buy a new one, the stocker will be just fine

JeaneZ28

iTrader: (3)

Just port your MAF.

kinglt-1

iTrader: (26)

The stocker is fine to 500whp. After that SD is the way to go imo.

corvet786c

iTrader: (6)

Do What I am gonna do. Mine is Ported inside. Screen removed and divider removed. Its all open up and smooth inside. Compared to a plastic ported MAF Housing the stock aluminum should flow over 1000+ CFM with an aftermarket airlid. Good enough for h/c/i iMO.

bowman2005

iTrader: (41)

Keep the stock one and port it becaus I put the 85mm slp on mine and a few people were like why did you but that...soooo I found out that the stock one is a beast

96RamAirTA

iTrader: (6)

there a how to port the stock maf?

streetassasin

iTrader: (30)

IMO, stocker or speed density

2001ws6-500hp

100% true, people say the stock is only good to 500 hp because thats all that the sensors are good to. they can only read so high. as for the flow rate of the maf, if u want to do anything above stock i believe in porting it. why have a 90 mm tb or bigger intake, when the maf is like 70? pointless. thats like putting 4" tru duals on your car then right in the middle, putting in a section of 2" pipe

HTX

iTrader: (1)

i hear that you can pick up a c5 zo6 MAF for $100. and it is 85mm.

There have been tests that show that the larger lid and MAF on camonly LS1's are good for 5 pounds all across the curve. Im sure on a cam only LS3 you would b looking at 10+

blackfang

iTrader: (2)

Edit- nvm.

LS1-450

iTrader: (33)

More, "port the MAF" nonsense. You guys should start a club.

Don't port the MAF. As has already been correctly stated in other MAF related threads, if you port the MAF, it will no longer read airflow accurately. There is no linear scaling that can be used to predict the resulting airflow after porting. Stock MAF's will read up to 512 g/s airflow. It's a measuring instrument. There is also the option of removing the MAF & running speed density.

A good option is to go to an 85mm MAF & de-screen it, then have the MAF table re-scaled. 85mm MAF's max out @ 11250 Hz, where the stocker maxes out @ 12000 Hz. Both MAF's scale out & 512 g/s airflow. Reason the guys don't like the 85mm is usually because they didn't have the table re-scaled or they ran out of frequency & didn't adjust the highest few columns to equal the higher airflow @ the lower measured frequency.

If your LS3 is not moving more than 512 g/s, then an 85mm de-screen & re-scaled MAF will do the job for you. If you want to see if the MAF is a restriction, watch the MAP pressure. When it starts the drop, there is a restriction somewhere. Could be runner, head, valve opening, plenum, TB, cold air intake or MAF. When all others have first been eliminated, then the MAF gets changed; removed, de-screened or replaced.

There are several, well respected tuners on this site that can help you. Send them a PM or start a thread in the tuning section, they will reply. Names that come to mind are JoeCar, FROST, Waitformeperformance......& several others. Good-luck