View Full Version : MAF mod

08-10-2009, 11:56 AM
Is it a benefit to do the MAF Mod? http://www.cintcc.com/mn12performance/mn12how-to/maf/maf.htm

08-10-2009, 01:40 PM
Nope, waste of time, and that MAF has been measured to flow about 680cfm the way it stands... so I figure you'd be good to about 300rwhp before you'd need to upgrade.


08-10-2009, 04:53 PM
Thats all I needed to know :)


XR7 Dave
08-11-2009, 09:37 AM
Well, just to clarify a little further what Fraser said, the physical dimensions of the MAF are not the issue. The original "MAF mod" that was outlined on MN12 Performance borderlines on stupid in the first place.

1) The stock electronics on the 89 MAF limit readable airflow to about 450cfm. After 450 cfm, regardless of how much air may or may not flow through the meter, no more air will be recorded, which means that the electronics will limit fuel delivery to the motor before the CFM limit of the MAF is reached.

2) The stock electronics on the 95 MAF limit readable airflow to about 450cfm. So even though the 95 MAF flows 680cfm, the electronics quit the program at the same basic airflow as the early MAF making the bigger MAF pretty much useless.

3) The MAF Mod detailed on MN12 Performance attempted to increase the CFM capability of the MAF without changing the sensor output. This is the reason for drilling out the sample tube. This is fallacy. Since the sensor output is still limited to 450cfm, there is no possible gain from this mod. All you can possibly accomplish is to create more opportunity (through more unmeasurable air flow) to cause severe top end engine lean out.

But even that really isn't possible because the stock injectors will also max out long before the newly "ported" MAF runs out of CFM capability. The MAF mod idea was an unfortunate combination of "carb technology" thinking and EFI that simply didn't work.

4) Now if you really wanted to make some progress, what you'd do is port out the MAF (and remove the center post of course) but NOT alter the sample tube at all. If you do this correctly, you can increase CFM to about 750, and change the calibration from stock (30/36lb injectors) to a 60lb calibration. But, it's not a precise science, and depending on how you do the porting you could end up with anywhere from 42lb up to 60lb calibration , so having a QH or similar tuning capability is absolutely necessary to pull this off successfully and without risking damage to your motor.

So in the end, the stock 89 MAF is perfectly fine with the stock 30lb injectors. The 95 MAF housing will work ok on an 89 with stock injectors also and may result in a gain of about 3rwhp at high rpm, but neither MAF is any good with bigger than stock injectors without modifications (NOT the "MAF Mod" referred on MN12 Performance) which WILL require tuning.

Therefore the average SC'er is going to be way further ahead by buying upgraded injectors and MAF's at the same time and finally by buying a chip that is calibrated to recognize both items.

Clear as mud?

08-11-2009, 12:42 PM
That's what I was going to say.... :p

08-11-2009, 08:55 PM
So I have the 94/95 maf and the 94/95 injectors 94/95 Superchager on my 93, what should I do then? Just get the chip and call it good or will a port of the maf help me?


XR7 Dave
08-11-2009, 09:14 PM
So I have the 94/95 maf and the 94/95 injectors 94/95 Superchager on my 93, what should I do then? Just get the chip and call it good or will a port of the maf help me?


You have to get a chip. Stock MAF's are NOT calibrated. They are matched to the car (model, year) they came from, NOT the injectors they happen to be installed with. Right now you have an MAF that doesn't match anything you have (wrong EEC, wrong injectors).

08-16-2009, 08:01 PM
After reading this article I decided to atleast look into adding an aftermarket MAF.


08-16-2009, 09:44 PM
A stock maf may electronically be enough but th esize may or may not make it a restriction dependant..REGARDLESS,,,Bad mod..bad mod

01-17-2011, 05:37 PM
I go with the cheap on maf's Before having them tuned a markVIII maf is a decent upgrade or of course the Lightning maf. On the 4.6 NA cars I use 02/03 gt mafs. No calibrated aftermarket maf can make up for the lack of proper tuning. When you are pegging the maf get a bigger one and have the pcm programmed with it.

10-24-2012, 10:16 PM
Would an aftermarket chip like Jet Chip be able to program a new MAF without going to a dyno?

10-24-2012, 11:07 PM
the only way to properly tune a supercoupe ecu is with fraser and dalkes definition files

the other software out there simply doesnt have access to everything that should be modified

im sure theres quite a few gents here that can get u situated

in the future dont hesitate to create a new theead as your question is unrelates to the OP, just makes it easier to get more sound advice

11-08-2012, 01:20 AM
even if the mafs is altered the computer still reads it as what its set as stock...bad idea..

06-17-2013, 11:05 PM
my experience has been with the pro m racing 80mm maf. It was calibrated to 60lb injectors. However, during the tuning process, the AF was on the rich side even though it was matched/calibrated by pro m.

In other words...when you start messing around with things that can change your AF ratio, you need to be careful and get it tuned properly.

These guys are right, unless you are doing the other modifications to support 300hp, the money is probably better spent elsewhere...