Pish-posh. I ripped that bastard out the first week I had my camaro. Ripped it out with extreme prejudice. Hatred, even. Stupid, stupid restrictive piece of crap. Ripped it out and stomped it... then I spit on it. Went and killed its whole family too. Even its little dog.

 

TPIS did this on a 1994 Camaro LT1 and published the results in their book titled "LT1 Hints and L98 Update"
They started with a completely stock intake tract. Measuring the airflow through the the complete inlet path from airbox through the TB, by removing the MAF screen they gained 24cfm in airflow.

 

The issue is not so much air flow capacity, the issue is accuracy and repeatability of the sensor measurements. A quoted "flow" without a corresponding pressure loss is meaningless. And, if the total flow capacity of the sensor is well beyond the engine's appetite for air, increased capacity means little.

Its your car... do whatever you want with it. You may gain, you may lose, but as long as you are happy with what you did, its "beneficial". The intent of my online scanner guide is to provide people with a brief technical understanding of what they are looking at when they do a PCM scan. You are free to disagree with anything I say or think. Its not going to change my mind, and its not going to change yours. I have complete confidence in my knowledge and expertise, and most people seem to respect my advice and opinions. But, as I said, feel free to disagree.

 

LOL that was hilarious.

 

Taking into consideration how many times its been argued in the past, I declare that this horse has officially been beat DEAD 100X over.

Unless someone can produce proof of a CFM restriction all you guys are wizzing in the wind.

 

I'm on the fence about this whole descreening the maf thing. So I just put a big hole in the middle that took out 50 percent of it. So either way, I'm good to go.

 

I think someone should manufacture a larger MAF screen with half as many veins allowing for laminer airflow and providing less restriction

 

The SLP Z06 MAF on my car didn't come with a screen.


David

 

Perhaps the design of the Z06 MAF was such that they did not need to incorporate a screen. Unless the reason is known, it's a leap of logic to suggest screens are uneeded because some have none.

 

Actually a detail people often neglect is the intake tract in front of the MAF, if there is a sharp bend right before that will affect the way the air flows through as compared to something with some straight length. IMO in that is the answer to why some MAFs have screens and some don't.

 

GM removed the screen from the C5 ZO6 engines during the production run. They claimed this was possible because of the symetrical layout of the intake track. They also claim it netted them 5 HP on the stock Z06.

As Shoebox and Dwayne have correctly pointed out, its the path the air has to take to reach the MAF sensor that affects the air distribution through the MAF. And yes, adding a CAI can affect the way an unscreened MAF sensor works. That's why Granatelli (as lame as the product may be) now sells two different calibrations in their unscreened MAF.... stock and CAI versions.

If you feel its a good idea, give it a try. Can't hurt anything. Just don't use the "so easy a caveman can do it" approach and hack the screen to bits taking it out. The early years have a spring ring that gets pulled out to allow the screen to be removed in a non-destructive manner.

 

Please tell us EXACTLY how you feel regarding the:
Water flowing through the throttle body.
Horse ******* on the bottom of the intake elbow.
Catalytic converters.
M6 skip shift.
MPH limiters

Please dont hold any details back this time.
I really would have expected you to crush it into bits and blast it into oblivion.

 

i personally descreened my maf then bought custom ported ends and noticed nothing at all. doesnt the computer ultimately use the readings from the o2 sensors to determine fuel anyway?

 

Only in closed loop. It reads the mass-air flow from the MAF sensor, divides by the target A/F ratio, and sets the pulse width to deliver the resulting mass-fuel flow. If the MAF measurement is off, the O2 sensor feedback allows the PCM to correct for the error using the long term fuel corrections (BLM's). When the PCM goes into power enrichment (PE) mode, it will disregard the BLM's if the PCM was reducing the fuel rate using BLM's less than 128. If the PCM was adding fuel in closed loop, with BLM's above 128, it will use the Cell 15 BLM's in PE mode. But that assumes the error at part load (closed loop) conditions is the same as the error at WOT, and that isn't necessarily so.

The Granatelli takes advantage of this. It alters the sensor output so its pretty much correct at low flow, but under-reports flow at higher air flow, where it is more likely you will be operating at WOT. That leans the PE mode A/F ratio out, and that will typically produce a HP gain over the stock over-rich PE mode target A/F ratio. That assumes that Granatelli has properly calibrated the sensor to begin with, which is open to debate.

 

Wow! I've been wondering how long this thread would go. I have the
"hated" screenless Granatelli MAF and it works just fine. I guess since
my intake tract is straight it's OK. I also yanked the screen out of the
stock MAF years ago based on the TPIS LT1 tips.

Would I do it again . . . maybe . . . maybe not. If I were dyno tuning
then yes . . . otherwise probably not.