SCT "big" MAF, 2800 series maf on a 26? any luck

[SullivanRacing06]

has anyone here on the forums used either on of there mafs on there rb? im interested in going with the 2800 series maf which is said to be good 750+ hp, im considering using this maf instead of twin z32s, currently im using the stock ecu, greddy 720s, stock twin gtr mafs and a apexi neo afc, any input would be greatly appt!!!

heres a link to the maf, for sale in other stores for 207.99 shipped this links just a example,

http://www.blowbyracing.com/sctba90mafme.html

[REDLN]

i also want to know if anyone has used one.

[gawdzilla]

i thought about doing this a few years ago, but ended up going d-jetro. you would probably need to guess/calibrate the MAF tables on an l-jetro at least. i'm pretty sure the safc wont have the configuration item to do this.

[Cjmartz2k]

Very interested in this as well.

[Yellow4g63]

If its the ford Lightning MAF then you should be able to find it cheaper than that. Just need a set the VQ tables for the map if your running stock chipped ecu. That's what I have for my RB20 but I'm going blow through with mine, even got this sweet adapter plate for it. http://www.vmptuning.com/store...nt=31

[Darius]

I e-mailed SCT over a year ago about getting the Voltage vs. Flow numbers from them so I could input the MAF curve into the PFC table. I mentioned that it was for a Nissan so plug and play was not feasible. They were total jerks and responded (and I quote) "We don't support imports." Nice customer service a$$hole...

[SullivanRacing06]

damm, what about the q45 maf/ is that a 4 inch inlet/ outlet? what kind of hp would that be able to support? or a single 3inch blow thru but only 3 inch nissan that can do 550 hp is the z32 correct? that max out to fast for my set up

[SullivanRacing06]

ne one with the info on the q45 maf for me plz

[Darius]

In theory what you can do is put a Z32 MAF sensor into a larger diameter housing and recalculate the Voltage vs. Flow curve based on the ratio of cross-sectional area.

[Carl H]

stuff a z32 sensor into a q45 housing and work from the z32 base vq map.

[gawdzilla]

q45 maf housing with the q45 sensor can meter LESS air than z32 maf housing and z32 sensor.

[WhatsADSM]

1) Run that sensor along with a known nissan sensor with the 2 in series. Make sure you don't have any boost leaks.

2) Drive around and log the output of the unknown sensor along with known sensor (i.e. known flow).

3) Create a transfer function or table based on that data.

Did this on my old RB20 and ran a 3" GM/Hitachi sensor in blow-through.

[Carl H]

fwiw, and this is all on speculation the q45 sensor is the 'same' as the rb20/25 sensor but in a different diamater pipe.the q sensor can read 450ish hp so if it is in theroy just a modified rb20/25 sensor then the .5" increase in maf pipe id translates to another 150hp of airflow.now this is not hardcore verified data but if that were to hold true then a z32 sensor in q45 housing SHOULD read more air due to the larger id of the sensor housing.

[SullivanRacing06]

but then again twin stock z32 mafs will read 500- 550 whp a piece? i think ill either stick with twin z32s or buy this emanage set up from another guy on nice for 400 w harness n prob convert to map, not sure still, damm

[Darius]

Many people with an RB26 have upgraded thier MAF sensors to twin Z32s. You would have to have a way to input the maf table into the ECU though so a standalone is required to do this.

My vote is to convert to MAP only. Much cleaner bay and just as tuneable as having MAFs.

[Carl H]

you could be quick and dirty with it by running twin z32 sensors and then using a voltage adder/divider to shoot one maf signal to the ecu much like the safc does for the rb26.

[WhatsADSM]

you could be quick and dirty with it by running twin z32 sensors and then using a voltage adder/divider to shoot one maf signal to the ecu much like the safc does for the rb26.

You are just trying to average the 2 voltages correct? A circuit that adds and then divides is much harder than just using 2 equal 1% resistors, something 1k-10k.

[Carl H]

would you mind explaining how the resistor setup you posted works...im not gonna lie its been a long time since my physics class where we did power and reistance.

[WhatsADSM]

would you mind explaining how the resistor setup you posted works...im not gonna lie its been a long time since my physics class where we did power and reistance.

It's may day job... well sort of. I actually am a firmware guy, but have a pretty good working knowledge of hardware.

Not sure if you are familiar with a standard voltage divider, but that is effectively the same thing, just that typically they explain a voltage divider with one side grounded, the other at a voltage level and 2 resistors in the middle. In this case both sides have an arbitrary voltage level and 2 resistors in between.

But here for the sake of argument I will use the following explanation. The voltage values are simply to illustrate the concept. Lets say the top MAF in the picture is outputting 4v and the bottom MAF is outputting 2v.

V=IR

So in our case we know the combined R (1k + 1k = 2k), and we know the delta in voltage (4v-2v = 2v). Solve for the current thorough both resistors and you will get (I = V/R = 2v/2k = .001A . So because the 2 resistors are in series with each other this is the current through BOTH resistors.

So now that we know the current we can get the voltage at each of the nodes. So again knowing V=IR and now knowing the 1mA current lets figure out the voltage drop across the TOP resistor. V=IR = 1mA * 1k (remember just the top resistor) = 1V. Since there is a 1V drop that means the at the middle point in the drawing there is 4V-1V(drop across the top resistor) = 3V.

Now just to be sure lets verify the voltage drop across the bottom resistor. Again we have 1ma and again (because I told you to use 2 of the same sized resistors) we have 1k. V = IR = 1mA * 1k = 1V. So the voltage drop across the bottom resistor is also 1V. And that makes sense since the middle point on the drawing is 3V and the bottom MAF is outputting 2V there is a 1V drop (3V-1V = 2V).

Feel free to try it with any numbers on the MAFs. But as long as you use two of the same value resistor you and put them in series like that, the middle point where the 2 resistors connect will be the average of the 2 voltages being supplied.

[Carl H]

ah yes, now i remember why i chose chemistry instead of mech eng...lol.i actualy dusted off my old physics notes and refreshed myself but thanks for the explination anyways!

[drftnrps13]

kind of off topic but if u convert to a map sensor say with the greddy emanage ult. what do i do with the orignal map wires? just remove them from the harness?, tuck them back(since the new map sensor comes with its on sponsor that plugs directly into the emanage)sorry off-topic

[Yellow4g63]

1) Run that sensor along with a known nissan sensor with the 2 in series. Make sure you don't have any boost leaks.

2) Drive around and log the output of the unknown sensor along with known sensor (i.e. known flow).

3) Create a transfer function or table based on that data.

Did this on my old RB20 and ran a 3" GM/Hitachi sensor in blow-through.

What do you drive now since you got rid of the rb20?

[WhatsADSM]

kind of off topic but if u convert to a map sensor say with the greddy emanage ult. what do i do with the orignal map wires? just remove them from the harness?, tuck them back(since the new map sensor comes with its on sponsor that plugs directly into the emanage)sorry off-topic

You mean what do you do with the original MAF wires? Most people just tuck them back, but if you really wanted to open the harness up you could remove them all together. Also realize that the emanage is just a glorified piggyback and if you use the map sensor to the emanage the map sensor input will go to the emanage and the emanage airflow output wire will actually connect up to the STOCK MAF airflow wire (part of the wires you will tuck away, but most people just splice it in at the ECU)

What do you drive now since you got rid of the rb20?

Used to have a 95 with an RB20 in it.. At the time I was a poor college kid and couldn't afford much so I used the GM 3" sensor which is a fantastic, well flowing and cheap sensor. I actually made a sort of one off fuel computer (again I was cheap) which was essentially a translator (translated GM sensor to RB20 sensor) and a SAFC in one.

So I had some experience doing exactly what is described here. I had to correlate the output of the unknown GM sensor to the known RB20 sensor.

Now I got a 98 with a 26 in it. There are some pics of it in this thread I did a while back about the LS2/LS7 coil swap:zerothread?id=353832