What MAF will do 1000whp?

[S14-NEO]

that will be a definate..im going to be using the head off the NEO setup thats currently in my car...im going to be throwing in another NEO setup in my car for teh time being cause im tired of being without my car..lol

[sickness14]

I wish i could do that :/

[LSV8mike]

Hey guys, my name is Mike and I am new to the forum. I have been lurking for a few years to find information on a periodic project I am helping a friend with. I found this thread, and figured it was time to register.

Said project is an S13 RB25 swap. It has been running/driving for a few years now, but small changes have been made here and there when time has permitted. Just like any project!

The latest task is going to be rerouting the intercooler plumbing. In doing so, we plan to run an atmospheric bov and blow-through MAF. This is my first RB25, so I have had a lot of learning to do. However, it is certainly not my first turbo/maf project... so I planned to use a set up similar to the Ford builds I have done.

In my opinion, the Lightning MAF is old news. The hot new sensor to us Ford guys is what we refer to as the "Slot Sensor". It is a Hitachi made hot wire sensor with an integrated sample tube, providing an analog 0-5v output. The sensor is also commonly known around some of the forums as the "05+ sensor", as it was first seen in 2005 and up Mustangs and other model Ford vehicles.

The real beauty of this sensor is its mounting posibilites. Factory made housings are not needed, and the sensor can be mounted into any shape/size tube with a custom flange. Allthough, tube housing are also available in many diameters for those wanting to just clamp a unit in line and go.

The stock Ford unit is good to roughly 300whp mounted in a 3" tube in a blow through set up (5v @ 47Lb/Min). However, the aftermarket version made by PMAS (HPX sensor) is good to 650whp in the same 3" tube. Step up to a 4.5" tube and the HPX sensor can support upwards of 1000whp.

The stock Ford unit is the same sensor on all 2005 and newer Ford vehicles, so finding one in a junk yard is easy... and can usually be had for under $40. (I got my first one for free!)

The HPX sensor is a bit more expensive.. but very affordable compared to some other aftermarket sensors that require a specific housing!http://www.vmptuning.com/store...nt=30Associated flanges and tubes can also be found on that site.(Also, I don't mean to sound like a salesman. I have nothing to do with VMPtuning or PMAS in any way... just giving info here.)

Anyway, the plan is to run the HPX sensor in blow though on this RB swap. I have had great results running it in blow through on my Ford vehicles, and I expect the same on the Nissan.

It seems like you guys are having a hard time finding transfer functions on some of the stock Ford sensors (Lightning 90mm, etc). You really need to poke around some of the Ford forums, that's where you will find your info. Here is a link with a few spread sheets of different for sensors:http://rothfam.com/maf/tools/http://rothfam.com/maf/

If using the HPX slot style sensor, the transfer function get even easier. Just put your dimensions into this tool:http://vmptuning.com/sct/HPX%20TOOL.xls

I'm not sure why the units are not noted... but they are kg/hr. Really not sure what units you JDM guys use, but incase you do not know the math, here is a great converter: http://www.translatorscafe.com...in%5D/ (Link is set default to convert kg/hr to lb/min... I use lb/min to tune, and you will notice most of the Ford transfer functions will also be given in lb/min.)

I will also post 90mm transfers for you guys in a separate post to keep clutter down on this post.

Hope this helps some of you! Happy to finally be a member! Tons and tons of great info on this forum.

Mike
Modified by LSV8mike at 6:07 AM 2/2/2010

[LSV8mike]

As promised in above post:

2001 Lightning (CNX1):5.000 1741.8084.907 1741.3014.639 1739.0204.443 1535.7414.248 1350.7124.053 1182.6653.857 1030.0793.662 889.9143.467 762.4213.271 653.1783.076 516.3072.881 406.3042.734 343.4442.588 285.6542.441 246.8742.295 203.0252.148 170.0752.002 144.9821.855 121.9161.709 101.1321.563 82.8831.416 66.6611.270 53.7341.123 39.034.977 28.895.854 23.065.732 17.236.635 13.180.562 11.152.000 .000

2001-2002 Lightning (ABU2):5.000 1741.8084.907 1741.3014.639 1474.9104.443 1302.0474.248 1145.1524.053 1002.7053.857 873.4393.662 756.5913.467 650.8973.271 555.3413.076 469.1632.881 391.8562.734 339.1352.588 290.9772.441 247.1282.295 209.6152.148 176.9182.002 148.7841.855 124.1981.709 102.6531.563 84.1501.416 67.6751.270 53.7341.123 41.315.977 30.923.854 23.319.732 16.729.635 12.927.562 11.152.000 .000

2003 Cobra (RYAK1):5.000 1726.3464.796 1515.2104.460 1234.3724.199 1040.4724.053 942.8883.718 745.6923.425 594.1213.317 542.4143.078 442.2962.808 343.4442.669 295.7932.572 266.1382.424 226.8512.339 208.0942.249 189.8452.158 170.0752.046 150.0511.922 130.0271.781 109.7501.624 89.2191.442 69.1961.352 59.3111.244 49.6791.119 39.540.971 29.655.792 19.770.680 15.208.546 10.139.072 .000.000 .000

Transfer functions for Ford sensors are usually given with at least 30 plots. The units given above are Volts vs Kg/Hr. Convert to whatever you need. (Some of your systems might also use "counts" rather than volts... google should be able to provide you with a conversion calc for that too... just a heads up.

Even the big dog aftermarket 90mm sensors (SCT and the likes) are only good to 850rwhp in draw through and about 650rwhp in blow through. I feel the slot style sensor is the way to go for 1000hp builds wanting to run a single MAF sensor. They also have a high enough resolution to offer a great idle.

Modified by LSV8mike at 6:16 AM 2/2/2010
Modified by LSV8mike at 6:19 AM 2/2/2010

[Darius]

Great info! Very helpful to have some Ford background in here to give us the low-down on their newer MAF sensors.

I definitely like the lower price of the HPX than the SCT MAF sensor. The only issue I see with any 650-900hp blow thru application is large diameter intercooler piping (3.5"-4"). That doesn't help the lag issue on a small displacement motor that is already running a large turbo for its size.

The key to the whole conversion still lies in converting the kg/hr provided by the Ford community into the convoluted japanese tuning software that doesn't know its own input units. (I called Apexi USA and they didn't know the units, they said it is in units of "flow"...duh) I'm pretty sure I know the conversion for the PowerFC, but I want to have someone try it out before posting it. Seriously, someone needs to step up and be the guinea pig

[LSV8mike]

The only issue I see with any 650-900hp blow thru application is large diameter intercooler piping (3.5"-4"). That doesn't help the lag issue on a small displacement motor that is already running a large turbo for its size.

I hear you on that one. Anything larger than 3" just seems crazy for charge pipe on such a small engine. Draw through is always still an option. You will have better resolution, and more range in a draw trhrough config... you will just have to tune properly for backflow and atmospheric BOVs when street driving. The Ford crowd has software based backflow fixes, so I'm sure you guys do too.

The key to the whole conversion still lies in converting the kg/hr provided by the Ford community into the convoluted japanese tuning software that doesn't know its own input units. (I called Apexi USA and they didn't know the units, they said it is in units of "flow"...duh) I'm pretty sure I know the conversion for the PowerFC, but I want to have someone try it out before posting it. Seriously, someone needs to step up and be the guinea pig

I am not familiar with the PowerFC... so I have never even seen said units. Can you give an example of high/low units given for a specific sensor, then what that same sensor is supposed to support whp wise? I'm sure we could figure out what the units are with some trial and error. (Unless of course they are made up units, haha... totally possible).

Before finding this thread, I too had planned on testing the Nissan sensor in series with a Ford sensor of known values. Maybe it's time to give it a try? I have both a sensor from an RB25 and a 91 N/A 300zx. I'd for sure be willing to set up a little leaf blower bench test with a 90mm vs either of the two Nissan sensors I have available. Just need to find the time.

(BTW... the Z32 sensor you guys are reffering to... is it an N/A or the turbo MAF? Is there a difference? I have never seen under the hood on a turbo 300... but have absolutely raped an N/A model for parts.)

[gawdzilla]

(BTW... the Z32 sensor you guys are reffering to... is it an N/A or the turbo MAF? Is there a difference? I have never seen under the hood on a turbo 300... but have absolutely raped an N/A model for parts.)

no difference. same sensor N/A vs. turbo

[Darius]

I'm sure we could figure out what the units are with some trial and error. (Unless of course they are made up units, haha... totally possible).

I have it figured out (98% sure) but I want someone to test my numbers out first to make sure they're right. I don't have the fueling mods required to do it myself.

[Yellow4g63]

Very good info for the ford Maf's.

[koukie]

I have been tuning SR20DET with Nistune for a few years. About a year ago, I converted my ECU to Speed Density with a custom translator box. From the data I collected about the Z32 MAF and its transfer function in nistune, the numbers are similar to the PFC.

From my understanding, these MAF values are arbitrary scalars. They are not anywhere near a unit in the tuning world. They represent a percentage of the maximum power output.

For example in Nistune, the Z32 range from 48-65535 and in PFC they are 0-7546. If you know programming, 0-65535 is the range for a word variable or short integer. You have to remember that these ECU are mostly hardware. It is not a PC that can store actual units.

You can make a transfer function using PFC Z32 voltage chart and compare the voltages to a Z32 MAF flow chart and correlate the two voltages to get a function between the actual gram/s and PFC values. Hopefully that function is linear or a high order polynomial with a good fit.

Once you get that data, you can possibly convert PFC to use with any 0-5v MAF. Of course with a little fine tuning of your own. In my case I was able to successfully convert to Speed Density and come up with my own transfer function.
Modified by koukie at 9:27 AM 2/10/2010

[LSV8mike]

From my understanding, these MAF values are arbitrary scalars. They are not anywhere near a unit in the tuning world. They represent a percentage of the maximum power output.

For example in Nistune, the Z32 range from 48-65535 and in PFC they are 0-7546. If you know programming, 0-65535 is the range for a word variable or short integer. You have to remember that these ECU are mostly hardware. It is not a PC that can store actual units.

Modified by koukie at 9:27 AM 2/10/2010

Good info! Thank you for confirming. A percentage of power output makes sense. I just hoped that one of the tuning companies would have translated those numbers into a unit of flow to aid in tuning/aftermarket.

For example, in the Ford world, all of the EECs use hexadecimal inputs/outputs. Like you mentioned, it's not a system that will store actual units. So the tuning companies will take the hex value at a given hex address and translate that into a common unit on the tuning interface. Those familiar with the address' and values can edit the tune directly via a hex editor rather than playing with the tuning interface scalar/table.

[240z4u]

BUMP!

hate to see an interesting thread die, I am going to do a blow through setup so I am very curious.

[Darius]

Buy a big maf so you can be my guinea pig!

[240z4u]

Yeah, not real crazy about spending that much on a maf. If I went that route and it was going to cost 300 I would likely go all in and change to haltech map based system honestly.

I generally won't do a mod unless replacement parts are plentiful and reasonably priced. The ford maf setups are very attractive.

Darius, Ill send you an email.

Evan

[LSV8mike]

Hey guys, been meaning to share this product with you all in this thread for a while. I'd like to get into details, but simply do not have time at the moment. Read up on it, play with the demo software, etc... and maybe we will discuss it later! haha

http://www.abacoperformance.com/products.htm

[240z4u]

Well seeing as how I am officially out of MAF and the BA3000 from SCT is now only $230 I think this is a go. Fortunately Whatsadsm (man I miss having him on here) is localish and willing to help me get this dialed in.

[PFL]

Have a look at this thread
http://zilvia.net/f/tech-talk/501118-ne ... ost5124687

[240z4u]

That's great, but there are no "ready to go" maf charts for a power FC which is the real issue. I already ordered a PMAS mass air sensor. My car is tuned on a maxed out z32 sensor. Looks like you've used a ford slot maf and changed the transfer function to match up with a z32 sensor correct?

If this is indeed what you've done, I am interested.

[PFL]

Yes that's what I've done. I own PMAS. I built the curves for the hpx, ba5000 ba 3000 ba 2600 etc. I can probably help build a chart for the nissan cals I've come up with.

[PFL]

Z32 transfer function volts and KG/HR
0.8 3.82
0.9 5.87
1 8.54
1.1 11.90
1.2 16.02
1.3 20.98
1.4 26.85
1.5 33.70
1.6 41.61
1.7 50.64
1.8 60.86
1.9 72.35
2 85.17
2.2 115.09
2.4 151.17
2.6 193.94
2.8 243.95
3 301.72
3.2 367.77
3.4 442.64
3.6 526.84
3.8 620.88
4 725.27
4.2 840.53
4.4 967.16
4.6 1105.66
4.8 1256.53
5 1420.28


PMAS HPX Ford /sctBA5000 (when used in 3" housing)
0.350 4.079
0.530 13.154
0.610 16.148
0.740 21.545
0.810 25.110
0.960 34.893
1.090 45.971
1.200 57.260
1.290 67.788
1.450 89.380
1.520 100.018
1.660 123.630
1.890 170.129
1.990 193.836
2.160 239.833
2.320 290.505
2.450 337.508
2.580 390.107
2.810 497.580
3.000 600.671
3.090 654.084
3.210 729.923
3.410 868.284
3.580 998.186
3.740 1131.640
3.880 1258.244
4.150 1532.097
4.380 1800.303
4.700 2226.392
5.000 2649.925

Here is the direct equation for the z32 maf.. use this to get flows for the exact
voltages used by the power fc. then compare the flows in kg/hr to the "units" in the power FC and you should have a way to figure it out.
FLOW in KG/HR=((VOLTS-0.17685819)/0.39215738)^(1/0.34572979)

[240z4u]

You own PMAS? wow.

Let me be first to say welcome, and thank you for the information.

[PFL]

You own PMAS? wow.

Let me be first to say welcome, and thank you for the information.

No problem. Let me know anything I can do to help you guys out. I've been tuning, hacking ecu's and building mafs for a long time. The least I can do is help you figure out what the stupid "units" are in the power FC lol

[240z4u]

I shot you a PM over on Zilvia.

[Darius]

Evan you have to let me know if my unit conversion into PFC "units" are correct!

[240z4u]

We're getting there

[PFL]

Did my equation help at all?

[240z4u]

Did my equation help at all?

I haven't done anything yet, I will work on it after I get the mass air sensor back from you. I was PM'ing you back and forth on zilvia.

[PFL]

Oh, ok..

[PFL]

Looks like it's "units" devided by 36 to get kg/hr to me

[240z4u]

I have a feeling you're probably right. Unfortunately I am a mathmatical retard, so it's gonna take me a bit to sit down and figure it out. I will also be connecting it in series at first and mapping actual output into the PFC maps.