Did you find the MAF reading on yours was higher at idle than the stock meter? When that happens it causes idle problems, but I found an addon to fix it. Ya know what causes it? Calibration, the blowthrough meter kits were calibrated for a fairly stock car, when you reduce restrictions the reading is slightly higher and it needs to be calibrated back to 25-35hz at warm idle.

 

Very nice

 

ok.. I got the final component I was waiting for, its typically used to adjust a Ford MAF sensor to calibrate a bigger sensor from a different car. I calibrated the voltage at Idle without scaling the entire output signal. I now have stock like idle, even better is I now have the adjustability for cams and idle speed.

Now I just have to replace my leaky diverter valve, and then readjust the idle value and I can go back to tuning. (Venting the valve to the atmosphere is FRIGGIN LOUD, even with a 1G valve, actually thats the only thing I don't like is the noise)

The turbo's "Jet engine whine" is more prominent now however. Now I just have to pick up a new intake pipe without any recirculation fitting on it.

I also am going to ask the designer of the translator if they would be willing to work with me to engineer a Speed Density version of the control box to make the conversion cheaper. (speed density doesn't work quite as well which is why most ford 5.0 mustang enthusiasts used to convert from speed density to the later maf sensor)

 

The blow-thru sounds great in the grand sceme, you can work your way past 500hp.
I know that Big Al (Dynoflash) got over 500AWHP with the stock MAF, so it's not a requirement to go blow-thru or MAP but it makes it easier to get the bigger numbers.

 

Yep.. this solution is more to eliminate the anomolous issues with a Karmann sensor.. its location, its sensitivity to vibration and "boom" from outside influences, plus even though the airflow capacity of the stock sensor is very high, the airflow becomes very turbulent and therefore becomes very difficult to accurately meter and tune at those levels (anything over 350whp seems to begin to experience this)

The stock airflow meter isn't truely a restriction, but as you get more air through it, it has a harder time "Counting" the vorticies and the Karmann "Street" either breaks down, or produces more vorticies than can register on the sensor so it either reads erratically, reads nothing, or reads a flat maxed signal.

 

posted twice made mistake.sorry m\j

 

great job malibujack your really chaulk full of very useful info.thanks for sharing it.

 

I really wanted to get this setup. Please keep us infromed on where we can find one at. Thanks.

 

im sorry, but what is the point of this mod? i really dont know?

 

Lots of points. Ability to run any intake configuration with no issues, better flow, adjustability, BOV VTA if wanted. Add this with a UTEC and in "MY OPINION" you have a better system than the aem. Mine is in the mail. I also think that when you compute air density, the closer you are to engine the better. Maybe not, but its seems logical. If the stock MAF measured density before the turbo, the air goes through the turbo, piping, intercooler, more piping then engine. So now whats the density measurment?? (jack, am i full of crap here??!!) Oh well, when the gt-35 gets installed with the rnr 2.4, i just didnt want an AEM with speed density..........RRR

 

Need for a modification is always subjective.. However an accurate measure of air density is important, since compressor effectivenes, and intake air temp are factors, placing it as close to the throttlebody (intake manifold) will reflect a more accurate reading. Speed density calculates these values based on RPM, Pressure, and throttle position (Possibly other information) however it can only make assumptions about airflow and therefore isn't always an accurate reflection of how much air is actually going into the engine. Its actually only an issue at part throttle or when the engine is under vacuum.. using a MAF sensor of any form, reflects the TRUE volume of air passing through it, you then use the air temp sensor to calculate its density.

When you begin eliminating restrictions in your intake tract, the stock sensor becomes upset and misreads, you have several problems with this situation, First is it reads differently and therefore requires that you retune for it. Also, things like cams and intake pipes alter the airspeed and airflow patterns into the stock MAF sensor which introduce idle problems, drivability issues, and of course, possible stalling when there is mild compressor surge or a large volume of air through the diverter valve into an aftermarket intake pipe disrupting or reversing airflow through the stock MAF sensor.

Mitsubishi chose the location of the MAF sensor for several reasons;

First is they used an available High-volume sensor that was designed for normally aspirated use, therefore using as a blowthrough was not an option.

Second, putting the sensor before the turbo improves throttle response slightly since as the turbo spools, it draws more air through it slightly quicker than a blowthrough setup might.

There are other reasons I can't think of offhand.

I should have some information shortly on additional availability for the blowthrough meter, several drawthrough meter options, a speed density option, and Karmann converters and signal scalars..

The things I gained with this new setup...

1) Placing the sensor after the BOV means its no longer a factor in air metering, neither is any intake component before the pipes..

2) I can now scale my injectors up to about 900cc's without needing to retune the ECU or UTEC

3) the adjustment module I purchased allows me to set idle signal, therefore I have the ability to adjust for new changes in modifications that alter idle airflow, such as cams, air filters, etc.. that would otherwise result in very rich mixture that may be uncorrectable with the BISS setting

4) I've removed the potential for signal clipping due to out of range values in the stock sensor

5) I've increased the overall airflow capacity of the entire system (the meter is capable of approx 600whp)

6) This solution will work with **ANY** form of fuel management and therefore can work with a reflash, s-afc, standalone, UTEC, XEDE, etc..

The downsides of this unit..

1) Slight lag in throttle response (though undetectable when your in boost, it only seems to be noticable in 5th gear cruising)

2) Expense, I won't lie, its not a cheap modification

3) Not plug and play (I will offer plug kits or eventually resell plug and play units)

4) Creative installation, you will need to modify or source an upper intake pipe (I will also souce the parts if necessary if I decide to sell these units) or you can choose a drawthrough sensor that bolts into the stock location and would require no modification to fit.

5) If you do not have a stock intake tract (Upgraded your intercooler, pipes, etc) and your base airflow has increased, you will need an additional calibration module, or the sensor would have to be calibrated which means you would need to measure the sensor's idle voltage output so it can be recalibrated.

Now its up to you.. I will also be in contact with the manufacturer of the Karmann converter to see if a less expensive speed density setup can be offered... but any of these setups will vary in price from $400 to $700... The truth is, if you need to retain OBD-II to keep the car smog legal, this may be your only option for this level of adjustability.

 

Oh, and a tidbit of information, the stock sensor for the mitsubishis are called Volume Air Flow or VAF sensors, Hot wire sensors are typically called Mass Air Flow (MAF) sensors.. but their used interchangably since they both function similarly.

 

Wow, my car needs a serious retune its lean now.. Since the Blowthrough sensor reads a lower MAF reading under load until the engine rpm's climb, I have to add 5-7% or more fuel from 2000-3500 rpm... I'll probably have to add fuel at the 0% column from idle through 4000 also.. Just want others to be aware of this if you attempt your own conversion.

It has a hell of alot more flow capacity since its calibrated for way more airflow than my car actually uses at the moment.. Very impressive..

 

Jack, sign me up for a plug!! and what ever that new adjustable thing is!! RRR

 

Still working on an OEM plug, I'd prefer not to use the molded ones if possible.. I'll let you know about the scalar tool and other stuff in a few days.