Should I? Really worth anything?

 

They do make for better airflow and an increase in performance... They do also have a tendency to make the vette run lean a bit so you might just run into that situation... Some say 5-8 HP on the upside!

 

they Work Great! But....They must be used in conjunction with a MAFT to get the full gain. Or you will run lean

 

Would the ported MAF ends be necessary if you use a MAFT?

 

I agree with jeffh355. Tune your car with the MAFT and stock MAF. If your car has a correct air/fuel ratio the gain is zero with MAF-ends or a OEM larger MAF such as the SLP and Grantelli. Those who experience a gain most likely had their air/fuel ratio incorrect from the beginning and got it right with a different MAF or MAF ends.

This is more discussed in the following thread: http://forums.corvetteforum.com/zerothread?id=280031


:cheers:

 

This might help me, I'm running rich since the TTS install? Any thoughts

 

They work good on 97-98s because they run rich from the factory... the maf ends lean them out a little to a more ideal setting. On 99+s they cause problems and can cause a loss of HP unless you know what your doing and have other "expensive" tools to work out the issues.

 

Porting the MAF may make you run a little lean since the MAF is no longer calibrated properly, but simply removing the screen seems to work quite well, and since the volume of the MAF stays the same the impact on air fuel ratio should be minimal, I would think anyway. My '98 TA I used to have picked up 8 rwhp from a ported MAF, my '00 vette picked up 6 rwhp from simply removing the screen. :D This was confirmed on back to back dyno runs, and later dyno runs did not show any loss of the gained power as the computer re-learned. For the money (free) I think pulling the screen is the way to go. :) New Z06's don't have a screen for a reason. Neither of my cars has had any problems as a result. Besides, if you pulled the screen and didn't like it for any reason, you could always buy a set of stock MAF ends pretty easily and cheaply I'm sure from someone that has replaced theirs with ported ends. :cheers:

 

As mentioned, the 97-99 cars seem to pick up power in the majority of the cases with MAF ends. This is because they run a little rich from the factory. The newer models seem to run a bit leaner so they can end up too lean with the MAF ends the resulting detonation could cause a power loss when the computer retards the timing.

The ultimate combo is ported ends in conjuction with a MAF translator and a diagnostic tool to read the o2 sensor readings.

Keep in mind that MAF ends not only lean out the mixture, they also result in more ignition timing.

However, as inexpensive as they are, usually worth a shot for the MAF ends. Some cars pick up 8-10 rwhp HP!

 

I'm still a believer of that a larger MAF or changing out the MAF ends will gain nothing. The gain some people can see is because the air/fuel ratio was wrong from the beginning and the new MAF or MAF-ends get your air/fuel ratio closer to be correct and you will gain some hp. Spend the money on a MAF translator to get the ltft's and WOT setting perfect.

The reason for me to insist about this is that DRM pulled 586hp/557ft/lbs with my stock MAF (no screen, 2000 model) with my new 427 engine. They added a Z06 MAF which have a larger diameter but could not find any more hp/tq on the engine dyno.

 

Sean you are very knowledgeable but I must respectfully disagree...

Ported MAF end DO In FACT increase HP. Here is why.....

With the stock MAF and a properly set A/F Mixture with a MAFT (Lets assume Base=0)

Then after installing MAF ends you are lean... So you bump the MAFT to +10% and everything is running great again. With the Proper A/F mixture

Based on those concepts the following HAS to be true.

More air is getting throught the engine.. Because you have to Add 10% more fuel to get the A/F right

If more Air and Fuel is getting throught the motor, then is MUST result in MORE HP.

I Autotaped before I added the MAF ends and I was perfect.
I add the ends and then Ran lean. I needed to add 5% more fuel. And I noticed it in my SOTP meter... :D

 

I think I would have to disagree with the above, I'm not saying a ported MAF won't increase horsepower , but the lean condition caused by a ported MAF is not the result of more airflow neccessarily, but rather rather slower airflow for the same amount of air. The MAF works by having the incoming air cool the little resistors in the middle of the MAF. The more airflow, they more they are cooled. This is how the MAF knows how much air is flowing. If you port the MAF, assuming the the same volume of air is flowing results in slower airlow, since it is now flowing through a larger opening. Therefore the MAF thinks it has less airflow than it really does, resulting in less fuel delivered, since in effect less air is actually moving over the little resistors(or thermistors is probably the more accurate term) since there is now more area for the air to flow around instead of over them. Basically you have thrown off the MAF's calibration slightly. You then adjust your MAFT richer to get the same amount of fuel you had previously for the same amount of airflow. This is why I recommend just removing the screen. Seems to give almost the same gains (6 rwhp on my '00) and will not effect the calibration as much, though it may still have a slight effect. Of course, if the car is runing rich, porting the MAF can lean it out and increase hp as some have said. Again, not disagreeing that ported MAF's increase airflow and power, just as to the cause of them making an engine run lean. :cheers:


[Modified by yellowy2kc5, 1:53 PM 4/25/2002]

 

I got nothing from removing my screen..

However the only other boost I felt that was better than the MAF/MAFT was the Vortex intake.. :smash:

 

Chuckster,

First, whats most important is that you are happy with your car and the setup you are using :yesnod:

I will give you the boring teoretical side of the story :) When adding MAF ends air will flow through the MAF that are not measured giving you a lean condition. The MAFT do not alter any fuel curves it only adjust the output signal from the MAF. The MAF is a airflow to frequency instrument.

To make it simple lets say that the MAF outputs 10KHz at a given airflow. Adding MAF-ends will increase the airflow through the MAF but it will still output 10KHz because of the amount of unmeasured air. Now you will have a lean condition because the PCM does not know about the unmeasured air.
Adjusting the MAFT to +10% will increase the output frequency to 11Khz at the same airflow as before which equals the true airflow including the unmeasured air. Now the MAF measures the true airflow and the PCM will know the correct amount of airflow which will have the lean condition to go back to normal. This means that the added MAF-ends will not increase power.

Or the short version, MAF-ends makes the MAF uncalibrated, then you use the MAFT to get the MAF back to a calibrated state.

Thanks.

:cheers:




[Modified by seanr, 9:54 PM 4/25/2002]

 

keep in mind maf ends have been rumored to cause tranny problems in auto's

run a search or ask on ls1tech.com.

imho it is not worth the risk for maybe a couple of horses.

 

Hi Sean, first off...It's very :cool: to be chatting with someone in Sweeden..

And your technical explaination is not boring. I actually find this stuff exciting.. :D

Anyway. My point is this..why is it that putting a cold air intake will increase the amount of air "realized" thus upsetting the A/F but the MAF ends are only an "illusion" of greater airflow. I am confused.

To test this. I'd do the following.. And not worry about A/F for now..
Metered air is metered air right? and since the calibration of the MAF does not change with the ends or the way it reads the flow.

I think by using Autotap should be measuring the frequency of the stock MAF through the full RPM range and graph it.

Then do the same with the Ported MAF ends. In theory the graph should show a higher frequency either across the full range or at least a peak somewhere..

What do you think? I can't believe all the manufacturers are wrong with the gains (minimal as they may be)

 

The ported MAF graph will show reduced frequencies.

 

Hi Chuckster, cool talking to you to :)

I'm not a airflow specialist but I know how a MAF works and I'm backing my theory by the fact that it was not possible to see any gains on a engine dyno going from a stock 2000 MAF to a large diameter 2002 Z06 MAF and this was on a large cubic engine (427)needing all air it can get.

I can not explain why a cold air intake can upset the airflow measurement in some cars, maybe it has something to do with the volume of air moving to the MAF or turbulence. Maybe someone with a degree in airflow could chime in.

I'm not sure I follow you completely but your suggested test sounds interesting but I do not think you will see any differences (maybe a very small) in the curve because the MAF will not measure the extra air flowing when adding the MAF-ends(assuming the MAFT has the same setting in both runs). :yesnod:

You would need to do it on a dyno measuring the airflow, the a/f ratio and the hp/tq to get any useful figures.

ToplessTexan,
Why lower frequency ?

:cheers:



[Modified by seanr, 7:33 AM 4/26/2002]

 

:confused: It has absolutely nothing to do with the tranny and no correlation what-so-ever...

Nick
God Bless America :flag

 

Smoke, but it does relate to the pcm and the pcm does relate to the tranny. do some research it has been pretty well documented that maf ends cause pcm to see less load causing the tranny to have lower line pressure. Please take the time run a search on ls1tech and make your own conclusions.