Raptor99

I know that people always say "don't waste your money on a MAF", blah blah.

Well, I'm in the process of getting just about all the bolt-ons. I've already done lid, headers, cutout, gears, stall, some suspension, and I have an LSX and ported TB on the way. So basically that's all of them, except a MAF.

I have one already (free from a friend) and I was wondering if I could gain anything by putting it on. I'm getting the car dyno-tuned next week (after all the rest of the mods are on) so I was wondering if there would be a difference. I remember hearing about 'calibration' of the new MAF, or something like that. How does that work? Can it be done with Edit?

So yeah, all the bolt-ons are going on, and since I'm doing the tuning anyway, I'm wondering if I should do the MAF too.

Thanks for the help guys!

cyphur

iTrader: (10)

The only time you're gonna see any sort of gain from the MAF is if you get the Z06 maf, for which there are known calibrated tables. that maf can be tuned for. the rest are crap. don't waste your money. the aftermarket ones are junk. stock MAF is good to ~650hp.

GuitsBoy

iTrader: (4)

Without stepping on cyphur_traq's toes - Im going to have to argue for the other side of the coin. Maybe the stock MAF will support 650 HP. But maybe a single 2.5" exhaust pipe would also support 650 HP. Everyone agrees that an air lid is a great mod because it eliminates restriction in the intake, right? Why then is the restrictive MAF good enough? Its all about freeing up HP. Maybe you can indeed run a 650 HP engine on a stock MAF, but how much HP are you then choking the engine out of? I mean you could probably run a 650 HP engine on a stock air lid or stock exhaust, but removing those restrictions will free up HP- in many cases, quite a bit of HP.

Now the real reason most should stay away from ported MAFs is because theyre a PAIN IN THE *** to tune. Why not just say that. If youre going to get your car tuned, and youre willing to take or pay for the extra time to tune the MAF, i believe there are lots of gains to be had. After all modding a N/A engine is all about removing a restriction, then finding the next restriction and removing that one... so on and so fourth. Why leave a blatant restriction in the intake? If youre willing to log all the necessary baseline tests with the stocker and then fully calibrate the bigger MAF - go for it!

Again, im not trying to step on anybody's toes... I just really feel strongly about the MAF issue. If its a pain to tune, just say so and dont make excuses for the stock MAF. Its like GM saying the piston slap noise is normal cause they dont want to deal with it.

-Tony

jimmyblue

iTrader: (11)

Ported MAF = no known-good cal tables.
Granatelli MAF = no known-good cal tables
SLP "'98-'00" MAF = no known-good cal tables
Pace "calibrated" MAF = no known-good cal tables
Descreened 75mm MAF = probably OK as-is
SLP "'01-'02" MAF = probably OK as-is but
suspect some mismatch to stock cal
Descreened Delphi MAF = use ZL1 truck table,
tweak for trims (needs tuner program).

Big pipe is better than small pipe as long as
you can get the fittings. Cheap big pipe (Delphi
truck MAF) is the only one that makes sense,
if you're going to step off from stock. Big, cheap,
known. Only thing better, would be free and
F-body calibrated.

Raptor99

So even though mine's free, it wouldn't be worth the hassle of tuning it?

I guess I can still descreen my MAF, because I've yet to do that.

Another_User

Just to add fuel to the fire:
New Lid = no known good calibration tables

GuitsBoy

iTrader: (4)

Sadly, this is so true.

V8er

iTrader: (2)

My question is >>>>>>> At what point is the stock '01 MAF a restriction? Will a 400rwhp H/C car make MORE power with a correctly tuned larger MAF?

This "larger is better" thing could be like installing dual 4" exhaust on a stock LS1. Obviously the pipes can flow more but it sure isn't going to make more (or as much) power as a good tuned 2.5" or 3" system. Similar for guys using 36# injectors on stock cars, no need for it!

So, what's the verdict?

GuitsBoy

iTrader: (4)

I think a car from stock ls1 right on up stands to gain from a ported MAF and calibrated ECM. Of course gains will vary on what other mods have been done. The more extensive, the greater the return. I would believe the gains to be on the order of what you see with a ported throttle body. Im looking at the spare stock MAF and spare stock TB side by side right now, and they look to have a similar total cross sectional area. Maybe on my car, with the relatively tame mods I have, I might see 5 - 7 from a TB. I would think that I could see the same from a ported MAF. With HP-Tuners and enough time, calibration issues become a null point.

-T

GuitsBoy

iTrader: (4)

What we really need to do is have someone with a speed-density (MAF-less) tune do a dyno pull with the MAF unplugged, but along for the ride, then have them run a severely ported MAF, also along for the ride. How Bout it? Anyone running a SD tune?

Another_User

I am running SD only now. I am also running a MAF replacement tube that I had custom cut. There was a SOTP difference IMHO with the straight tube, and a lot better throttle response. It also required additional work to the VE table, so it obviously changed the engine's airflow characteristics.

Here is my take on the entire thing: ideally you will want your MAF to flow the same or better than your throttle body. Think about it this way, if you have a 75mm throttle body, and a MAF that flows effectively the same as a 65mm tube or less (I don't know the specs, but we are just talking theory here), then you will see two things:
1) outside the MAF you will have normal air pressure
2) because of the MAF restriction, there will be additional vacuum formed in the intake tract due to the engine attempting to pull air into the intake through the TB, but being restricted by the MAF
The end result is you end up with all-around lower volumetric efficiency of the engine.
Once you eliminate this restriction you will have less vacuum in your intake (vacuum with the throttle open) and a greater volumetric efficiency. At WOT your engine's intake will be more efficient and it will come that much closer to matching the outside barometric pressure. Greater volumetric efficiency means more power.

I hope that makes sense.