What else changes with Aftermarket MAF

[MikeWS601]

I have a 2001 T/A M6. I finally have started to look into putting some mods into it. I am in the process of purchasing a K&N and a new air lid.

I have started looking into a new MAF, either from SLP or Granetelli. I have heard mixed things about these. Do they work well/provide nice power increase? Also, if I installed a larger MAF (85 MM) MAF, do I have to do any reprogramming to the computer or anything, or can I just hook it up and I'm good to go?

Let me know what your experiences are. Good or bad.

[2002ws6_mn6]

I know a couple of people who run an aftermarket MAF.. I do not. If you get a MAF you are going to at least need a scanner to make sure you didn't lean yourself out.

List your mods.. There are other mods you can do that could give you better gains and less problems.

[JandJsTA]

Originally posted by MikeWS601
I have a 2001 T/A M6. I finally have started to look into putting some mods into it. I am in the process of purchasing a K&N and a new air lid.

I have started looking into a new MAF, either from SLP or Granetelli. I have heard mixed things about these. Do they work well/provide nice power increase? Also, if I installed a larger MAF (85 MM) MAF, do I have to do any reprogramming to the computer or anything, or can I just hook it up and I'm good to go?

Let me know what your experiences are. Good or bad.

I ported one within the first 2 months of buying my 02 A4 and had nothing but problems but it was an A4....but I can show you more posts of people having problems with ported/aftermarket ones then I could show you successful ones :(

As far as tuning YES... you will need to work with the MAF table extensively to get it calibrated to the aftermarket MAF and you may never be completely successful and I am sure if you post around and do some searching you will hear more then enough stories to corroborate my opinion...... now if you're pushing more then 500HP .... that's another story :)..... save your money for a more worthwhile MoD ......

[smiley]

unless you are making over 500 hp - the stocker flows fine. aftermarket mafs are junk and not worth the headaches you will get afterwards. spend you money on something else like a catback...

[smiley]

since this comes up all the time... i we and snagged some info on the subject. it's not pretty - i just saved some discussions. some day i'll clean it up. anyone has anything to add.... post up!

http://smiley.tzo.com/fbody/atap/backups/maf.htm

[ws6dude]

save your money, go with somthing else like a Predator

[jimmyblue]

There are dozens of better ways to spend the price of a
Granatelli MAF. If you want the same effects, buy a used
truck MAF, punch out the screen, and solder a ~2.2K
resistor across the "live" legs. If you want stock cal, make
it a 2.7K. You'll be $300 ahead. Use that to buy the Dremel
you need for porting your TB, and a digital multimeter.
Save up the rest for a tuning/scanning tool (not to pimp
any names).

Don't worry about what the TeamZR1 dude says in the
notes from Smiley, he's talking about 'Vettes and their
electronic throttle is the only way you can drop the
airflow as far as he complains about. An F-body will
not let its IAC choke off the airflow that far. Not my
A4, for damn sure (I measured idle MAF frequency once
and it was way above being a concern).

[DebianDog]

I had posted this on the "other" board.

I already have a GMAF and when I was closer to stock it seemed to run better. When I got my cam, LT's, and injectors... tuning (for RWTD), was next to impossiable. I will give it another shot, at tuning it, once I have my own editing software as I will be near or over 500 HP on the hose.

I agree the the other post that your $$$ would be better spent elsewhere. It will also, possibly, mess up your shifts on an A4 like ported MAF ends do.

I took a WOT run recorded it then put the GMAF on and recorded a WOT run. It leaned me out and felt better. Felt better, but according to the data it did not run as well.

Stock:
http://dvmix.com/data/StockMAF.jpg

GMAF:
http://dvmix.com/data/GMAF.JPG

I know I am running rich. I am working on that ;)

[smiley]

Originally posted by jimmyblue


Don't worry about what the TeamZR1 dude says in the
notes from Smiley, he's talking about 'Vettes and their
electronic throttle is the only way you can drop the
airflow as far as he complains about. An F-body will
not let its IAC choke off the airflow that far. Not my
A4, for damn sure (I measured idle MAF frequency once
and it was way above being a concern).

i can remove that part - yes that is specific to vettes. like i said - i pretty much copied the other threads... lets get some more discussion going on in here on the subject!

[jimmyblue]

I wouldn't remove it, just annotate it so people with F-bodies
or other non-electronic-throttle motors don't get all off in the
weeds over it.

I have been collecting MAF tables for the stock F-bodies, 'Vettes
and trucks. Surprised me to find that all Delphi 85mm MAFs are
about identical (the difference appears to be the Z06 not having
a screen, and truck input tract differences). All of them are set
to make an F-body run very rich and all of them can thus be
"down-tuned" with the resistor trick or (and this is where I want
to go) by just-right porting. I know this because when I ported
mine, very lightly, just enough to take off casting flash, I had
to increase the resistor value by 22%. A more aggressive port
job could conceivably take it to where you needed -no-
resistor to get a proper freq/flow curve for an FBody PCM.
How cool would that be - more flow over the Z06 stock config
but tuning-benign?

I could use an Edit dump of an '02 MAF table (stock) still; only
have the '98-'00s and believe the tables changed.

Here is my plan: build a tandem duct with my shop vac, my
untouched '02 stock MAF and my ported SLP MAF in series.
Take out my current tweak resistor, and read frequencies
at full flow (if this isn't pegged out). Keep on touching up
the SLP (truck) MAF bore until the frequency matches stock.
Badda-bing!

If I get good at this I'll go looking for cheap truck MAF cores
and do some more.

[JandJsTA]

Originally posted by jimmyblue

I could use an Edit dump of an '02 MAF table (stock) still; only
have the '98-'00s and believe the tables changed.



What would you like JimmyBlue .. just the txt dump file??

[smiley]

sounds good!

[JandJsTA]

You've got Hotmail :D

[jimmyblue]

Yeah... I clean it up a little and then import it to Excel.

Just want to see how different the model years really
are, relative to the "folk wisdom" that the early years
were tuned richer. Though that might be somewhere
other than the MAF table - we'll see.

[Edit]

Thanks for the file. A couple of interesting things. One, in
the "normal" region of operation from 1500 to 11250, all
F-body year MAF tables are identical.

98 table stops at 11250. 99-up fill the cells above that,
up to 12000, with the same 439.2 value (dumb; why?)

98-00 have no values below 1500. 02 has values down
there but they look whacked, they do not increase at
the same "slope" as the truck MAF and are discontinuous
appearing as they approach the 1500 cell. If the Fbody
did try to run down at (say) 1400Hz the mixture calcs
would be for shit. Fortunately an automatic, at least,
idles well higher than that (like 2500 - 3000 Hz if I recall
my measurement).

Whatever tuning differences there are between the
F-body years have nothing to do with the MAF. Probably
more the EGR and injector size, flow table, fuel system
hardware differences.

Is there a place on this board where I could host this
Excel file? The Z06 data for example should let you just
program for using the Z06 (or truck) MAF straight-up.

[DebianDog]

Guess this is the chart comparing the GMAF to the 98 Stocker then?

http://www.granatellimotorsports.com/images/artlr/dyno012small.jpg

[jimmyblue]

That's a dumb-ass bunch of marketing drool attached to
that freq/flow chart if you ask me. It shows that the
GMAF will lean you out, and why would anything but the
stock MAF be the "standard of comparison"? Maybe if
you live in G-world?

If you draw a horizontal line from the GMAF to the
stock MAF curve, and drop verticals to the Flow axis,
at the top end theres about an 15-18% lean error on an
airflow basis. But they indicate the small frequency
error on this "marketing" slide, because that makes
it look like the curves are close. It's the X-axis error
that matters to the fuel calcs though. Yeah, a GMAF
like that will never give you "that dead rich feeling".
But no pinging at 15% short fuel from factory tune?
In your dreams....

On my charts the 85mm MAFs are all roughly located like
the Pro-M line (relative to the F-bodies). Richer, yes.

Thing is you can adjust a rich MAF yourself with cheap
components but a lean MAF you have no such option.

[slow]

that info earlier in this thread, sounds familiar ;)

Ryan <--- STOCK MAF

[smiley]

Originally posted by slow
that info earlier in this thread, sounds familiar ;)

Ryan <--- STOCK MAF

he made it over here ;)


jimmyblue - email myself or joe the file and we can get it hosted here no problem!

[ez98ls1]

I have an aftermarket mass air and I'm running rich as hell. I'll be putting the stocker back on to see if it helps me.

[MikeWS601]

thanks for all your opions. It sounds like I am going to consider some other MODs first.

[smiley]

Originally posted by ez98ls1
I have an aftermarket mass air and I'm running rich as hell. I'll be putting the stocker back on to see if it helps me.

what other mods do you have and how rich are you (ie - do you ahve some atap logs or soemthing)? generally a maf will lean you out....

[ez98ls1]

I recently had the car dynoed and from 2000 to 4000 I was around 11.7- 11.9. From 4000 to 6000 it went up to 12.9

[ez98ls1]

Forgot the sigs do not work
98 formula M6 NBM
lid, fram, pulley, y-pipe, LM, powerslots, mass air, 4.10's