MAF Question
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!
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
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.
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.
New Lid = no known good calibration tables
Trending Topics
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?
The Best V8 Stories One Small Block at Time
-T
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.
Last edited by Another_User; Sep 30, 2004 at 10:27 PM.

