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Would anything major (or minor) happen if I took the MAF screen out. My 01 has stock intake. My 99A4 had a vortex rammer and when I took the screen out, I noticed a little more surge on top end. :D
 

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MSiska said:
Would anything major (or minor) happen if I took the MAF screen out. My 01 has stock intake. My 99A4 had a vortex rammer and when I took the screen out, I noticed a little more surge on top end. :D
There was no improvement when I removed mine and it does surge a little when backing off the gas in 5th at 100 mph+.
 

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How do you take the screen off? I tried popping it off with a screw driver. It didn't even budge.

Thanks in advance.:)
 

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Z06 Maniac!!
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GM removed the screen on the '02 because they said they realized it wasn't necessary to straighten airflow on the Vette. GM claimed it accounted for some of the hp increase for the '02 Z06. DRM told me to ditch mine and so did TPiS. I did so, without any downside. Just stick the screen with a screwdriver and rip it the fu$k out. Just be careful not to stick the screwdriver in too far to avoid hitting and damaging the maf sensor.
 
G

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No difference on the dyno

Dyno testing shows no significant difference with or without the screen. We have seen 2 RWHP variance both + and - with and without the screen. It makes no measurable difference since the MAF with the screen outflows the intake manifold entrance, throttle body, and stock airbox, by 30%. Start with the airbox and change out the air induction 1st. Then the throttle body.

We will soon have an aluminum intake manifold that can be ported larger to allow some additional flow. This is good to a point, but porting beyond the cfm needs of the engine, is pointless and a waste of time and money.

Years ago, larger carbs, brought some additional power to the stock engine, but beyond the engine demand for airflow actually saw a decrease in low end performance due to the loss of velocity.

The 97-2000 MAF sized at 75mm, developed only 3 RWHP with the addition of 76mm MAF ends, but 0 RWHP at 77mm MAF ends. The LS6 MAF 2001-02 is almost 88mm. Way more than needed for max performance. In fact is is too big in my estimation, slowing the velocity of the intake charge.

This is why the 97-2000 Halltech TRIC sees 22 RWHP on average vs 16 to 17 RWHP for the 2001-2002 TRIC. The loss of velocity in the intake tract is not good for performance.

The honeycomb screen is designed just like the ones used in wind tunnels to promote fully developed laminar airflow.

The purpose is to allow the wire sensor (meter) to more accurately "read" the mass of air passing by. Without the screen, there is significantly more turbulence on the 2001-02 MAF and intake due to its size.

The 88mm id is much larger than necessary to feed 405 HP. In fact, in flows enough air with the screen in, to support over 650 HP.

The point of restriction after the air-filter and restrictive airbox on the Z06 and LS1 is the 75.5mm port entrance of the intake manifold making less restrictive openings larger or in this case removing the screen for more flow, pointless.

If the MAF flows 1200 cfm, and the intake manifold 900 cfm, as an example, taking the screen out to promote 1250 cfm is without benefit.

If the stock airbox flows 500 cfm and the engine demands 600 cfm at 100% volumetric efficiency, increasing the airflow by changing to a less restrictive air filter, will net positive results.

You can check out this link to calculate your cfm needs:

http://www.corvettec5.com Click calculators

Jim
 
G

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The T-1

was designed specifically for the 2001- 2002 Z06, and works perfectly with the 2002 MAF (screenless)

There may have been some modification to the 2002 MAF sensor from Delphi, vs just removing the screen from the 2001. For that reason, we sell the 2002 Z06 MAF upgrade, rather than just popping the screen out of the 2001 MAF.

The TRIC is NOT designed to work with the screen out. The additional turbulence which results from some forced air induction, causes a slight surging when decelerating when running 'screenless'. The 2001 MAF eliminates this slight surging at decel, without a loss of power at high rpm.

Ranger runs 12.1 @ 116 with his TRIC and screened MAF.
 

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I have a Zimmer computer 6 HP.
Corvette Concepts ram air 10-12 HP on a standing dyno.
mmmmmmm 425.00 for my computer program and 250.00 for ram air.
Does Ron take care of joe better than the rest of us.
I better make some calls 2morrow, sounds like I got fucked.
 
G

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MSiska said:
Would anything major (or minor) happen if I took the MAF screen out. My 01 has stock intake. My 99A4 had a vortex rammer and when I took the screen out, I noticed a little more surge on top end. :D
Think about this, assume you have 26 lb injectors.which are rated fuel flow per hour, thus at fuel flow of 8*26 = 208 lbs/hour.

Now a stock MAF flowing ( this is a tested recorded value via a PCM scanner) 3.5 lbs/min. so for an hour that is 3.5 * 60 mins = 210 lbs/hour.

Now go to WOT, the average airflow increased *4 of part throttle airflow volume, so (3.50*4) = 14 lbs/min * 60 = 840 lbs/hour.

Yank MAF screen, increases airflow to let's say 20%.
840+168 = 1004 lbs/hr.

Of course this was not real world, but you can see that in deciding to make mod changes, you need to determine how your other engine functions will take to those mods.

So as you can see by yanking the screen off the injectors cannot march the increased airflow and the end result will be too lean conditions, clearly when in long term WOT.

Thus the surge, and can be cured by going with larger SVO 30 ( are 36 lbs on a LSX) injectors ( best path) or at the least tune AFR richer with a MAF translator.
 

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Wouldn't the computer automatically dial in more fuel for the lean conditions during the relearn? The stock injectors must be capable of having more room for flow. I don't know. Do we have adjustable fuel pumps?

I was going to install an 02 MAF in my 01 w/ sidewinder. Now I shouldn't?:(
 
G

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Snce the EPA allows emmisons to be off by 1 1/2 times of the specs, this means fuel trims can be off by as much as 25%.
As long as LTFT is within that 25%, no error is flagged.
Thus the PCM is happy within that range and is not designed to have a perfect value of zero for LTFT.

The PCM will attempt to assure STFT is happy within its range of 10%, but does not go out of its way to calibrate for best performance.

It might try and get LTFT to zero but if you add more airflow, its a constant battle for PCM to get the tables perfect.

So you could have LTFTs of 23% lean, PCM is happy ( no DTC) but of course then knock circuits and timing are effecting best performance.

This can be dealt with by using a MAF translator which you adjust to force PCM to adjust till LTFT is closer to that perfect number of zero, thus ridding the knock and increasing timing.

The PCM job is more for EPA then it is for best calibration for performance changes due to mods added that are changing the windows G.M codes the PCM to hande.


ZEBRA said:
Wouldn't the computer automatically dial in more fuel for the lean conditions during the relearn? The stock injectors must be capable of having more room for flow. I don't know. Do we have adjustable fuel pumps?

I was going to install an 02 MAF in my 01 w/ sidewinder. Now I shouldn't?:(
 
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