Guaging Interest On New MAF Setup

[DSMs_Suck]

OK all after talking a bunch with Jake (TopStreet240) he convinced me to make a new MAF setup for the KA series guys. Honestly I would assume that this will work with the SRs, CAs and RBs as well however since I only have jakes 240 (ka24e) to test on and mine (stock ka24de) So I will only guarantee perfect operation on vehicles with the KA24DE and KA24E ECUs. Then once I get my RB setup all squared away I will ensure proper calibration for the RB ECU. I am currently a computer engineering student with an emphasis in embedded systems (In case you are wondering how I am doing all this =] )

Here is the deal... this new MAF setup is looking to replace the factory airflow meter with a GM 3" Air Flow Meter that can be run in either a draw through or blow-through form. This system is commonly refered as a "translator" setup.. i.e. where a common, easily available and VERY good air flow system (GM signal) is "translated" into a signal for air flow that the Nissan KA ECU can understand. This setup would COMPLETELY Replace the stock MAF while still using the stock ECU.This setup is a viable (in many cases cheaper and better)alternative to:- z32 MAF + AFC- Hacked MAFs (Again usually coupled with an AFC)- MAF + Jim Wolf ECU

Outline of benefits:- Horsepower increases and even spool time benefits based on the VERY GOOD DESIGN of the GM sensor.- Can compensate for injectors from stock injectors to 720cc- Allow for a draw-through OR blow-through setup.- If run in blow through, RECIRCULATION OF THE BLOW OFF VALVE WOULD NOT BE NEEDED. (blow off valves can be vented to the atmosphere without the ECU giving a ****). Also it is important to note that the sensor can be run in a 2.5" intercooler pipe without much of an issue with a 2.5"-> 3" silicon coupler, otherwise I have used straight 3" before with just a t-bolt on the 2.5" side and it seals fine. If you are running 2.25" piping then you will need to fine the 2.25" -> 3" couplers.- Intake pipes can be run in any way imaginable since the GM sensor doesnt care which way it is angled, situated, etc.- Would include a MAF that has been proven to support 500-550 whp. (If need be I can allow for a larger slightly more expensive MAF that will allow for more)- Will have AFC type settings that will be adjustable via knobs under the hood- Setup may be a plug and play operation if I can get my hands on the plugs, otherwise it would be simply cutting and slipicing of 3 wires- Free updates (you pay shipping both ways) if I ever come out with a software update.

The "AFC" correction type settings would work as follows:Allow for injector correction (global injector setting) and have 3 settings, One for low rpms (0-2000), one for mid (2001-4000), and one for high (4001-MAX). These would be adjustable by +-5% increments and would apply for ALL values of the throttle.

I am actually currently in development on it but in the beginning stages, so if there is anything you can think of speak up. My estimated release would probably be in two weeks or so.

Finally:I do need to gauge interest here. The setup would come with the Unit, Instructions, and a used (tested) GM 3" MAF. Pricing would actually be variant on how many I would end up selling, the more obviously the lower the price. As it stands now, they would be $350 + shipping for everything, on the assumption that this would only sell to like 15 people. or less.. thus its basically a pretty custom job. If I knew I would sell to like 25 or so I could do $300 with everything. Hell that is still tons cheaper than even a z32 + AFC, not even getting into the Jim Wolf Route.

Let me know what you guys think.

Murray

[Redline240]

Its certianly a interesting concept...let us know how it comes together...

Redline

[aleph1]

So...I dont get this. Is this supposed to work like a Hack MAF setup? 3" piping and same maf readings? Will you still need any AFC of sorts? I am very confused. +-5%? Thats not enough for even 370cc injectors...

[SingleCamSam]

I think this is a friggin' great idea. Depending on price and results i would definitely be interested.

Aleph. I think he means +/- 5% increments. i.e. you turn the nob 2 increments and get +/- 10%.

[spitz7985]

is that Jake from Top Street in Milwaukee?

[Red-KAT]

Where does a blow through go? Right infront of the TB?

I have never seen one so I dont know how it would prevent the prob of the bov.

[DSMs_Suck]

So...I dont get this. Is this supposed to work like a Hack MAF setup? 3" piping and same maf readings? Will you still need any AFC of sorts? I am very confused. +-5%? Thats not enough for even 370cc injectors...

SingleCamSam got it right on the nose. It would be a base "global" setting that would correct from 0% to 50% off the maf reading right away. So for example if you wanted to run 370cc injectors you would want to lean out 30% right off the bat. I.e. you would set the base setting to 6 (6 * 5% = 30%). On top of that you can run settings for three ranges of RPMs, low, medium, and high. I was planning on having each settings as +-5% however when thinking about it again each setting point may work better if it was +-2% (or maybe +-3%) to allow for a little more fine tuning. Again guys this would be mostly custom so I can leave it up to you guys... Honestly an LCD setup wouldnt even really be out of the question it just raises the price a bit.Basically this thing would allow for a pretty damn good tune, not completely what the afc offers (afc has 7 points for SAFC and I think 11 for SAFC2) although in most cases u only need like 5 or so. So, all in all you can run without an AFC and it will tune damn near perfect. If however you want more fine tuning then you can always interface an AFC afterwards.

So basically if you guys want I could make one with like 10 points of adjustment via an LCD and buttons for more... Then there would literally be absolutely no need for the AFC. Maybe I could add a turbo timer in there to try to make the extra cost offset...

This is actually Murray a best friend of the Jake's at Top Street Performance. I will be actually making the unit and testing it on both mine (NA 240sx to prove the value of the MAF setup) and Jake's KA24ET.

As far as where it would go blow through is up to you... literally the GM 3" can be mounted almost anywhere as long as you dont have it in backwards (note: there is a flow goes this way sticker ). Most blow through setups are run after the BOV and before the throttle body. The reason this eliminates the problem with the BOV is because when the BOV goes off all of the air is released and never even makes it to the air flow meter, thus the ECU doesn't see it. Where as in the draw through setup the air is metered right away before it goes into the turbo, and then within the piping system it is let out through the BOV and the ECU adds fuel for the air that is now let out to the atmosphere as opposed to going into the engine as it is supposed to... Hope the explanation helped, if u guys have any more questions about it I would be happy to answer them.

BTW I quick found a picture of the sensor online and uploaded it to the topstreet site (gotta love admin abilities =] ).Hopefully this link works:http://www.topstreetperformanc...l.jpg

[spitz7985]

hey man, i live in the milwaukee area, i've been down to top street and talked to jake and checked out his car. that custom equal length tubular manifold is amazing. last i heard the boost somehow went up too high and he fried the rings. has he rebuilt since then? i'll actually be stopping down sometime soon with my buddy to pick up his turbo timer he ordered. what year is your 240?

-Brandon

[1998cc]

I am definately interested. Just let us know how it goes.

[DSMs_Suck]

Jake basically did a stock rebuild but put in ceramic coated pistons. Yup his manifold is pretty nice... you should stop down and check out some of the projects coming together. I just got a 95 240sx SE, I used to own a VERY BALSY (all it was missing was a cage) Black 93 TSI AWD, that I parted out to pick up my 240 and start saving for a turbo setup.

I'll keep you guys posted... I actually plan on having a bunch of code ready before the parts actually get here, so I should have more info about it late next week.. And once the mounting is finalized of course lots of pictures, maybe video.

BTW I also found a typical install of the GM MAF in blow through this time it was on a DSM:http://www.topstreetperformanc...c.jpg

[MikeMurphy]

I would be interested only if it fell into the $150 range. I would also rather have more like a 2% fuel adjustment rate. You could actually probably run a very simple setup of 2 rows of 10 resistors and allow for 1% tuning quite easily. Im not an electrician but it seems to make sense to me.

I would much rather be interested in a MAF->MAP convertor that could emulate MAFS signals, while staying relatively inexpensive. I dont see why it cannot be done.

[DSMs_Suck]

Honestly the reason I went with the GM 3" MAF is because I know how all of the setups run. Honest to god the MAF setup IS a better air metering setup than speed density (MAP). Advantages:- Much faster response- Much more accurate transient air flow response- Mass Air systems return the TRUE air flow reading ...where as a speed density setup needs to rely on VE tables. This means that when you add exhaust, intake, cams or ANY mod to a speed density system that changes the way air flows through the engine... You will need to retune. Whereas, a Mass Air setup you can add whatever you want and the air flow meter will pick it up and you don't need to retune.

Disadvantages:- Under VERY high horsepower (over the 600whp range for this sensor and about 800whp for the LS1 3.5" sensor) the maf can be overrun.- It poses a very small restriction in the intake system. If you want on the 3" you can remove the screen with no ill effects, so this restriction is basically a few wires in the intake, and wont hurt horsepower any.

If you want to read more about the air metering systems goto http://www.topstreetperformance.com and go to tech info section then links and read the automotive thesis paper.

As far as $150 range.... No way, simply no way. You are talking about having a system that includes an air flow meter (from ebay it seemed as if z32 mafs are around $150 by themselves... and a 3" GM can easily perform with that, not to mention it mounts a lot better). Then on top of it you are including a system that adapts that signal to a Nissan ECU. AND at the end you even have a system that is a stripped down version of an AFC.

Or we could compare to the MAF + JWT ECU route.... Do you realize how much the JWT ECU mods are?

Also I have far more than $150 in it, just in parts. The system runs a dedicated 50 MHz microcomputer for all the data manipulation... This isnt some Radio Shack capacitors and resistors soldered together, this is a real mini ECU. Hell my system probably has more processing power than the SAFC and probably even more power than the fuel subsystem in the real Nissan ECU! Next we have my personal time to assemble the circuit, and all the research and development needed to find out all the calibrations needed to run this completely custom embedded system. I am computer engineer, this is what I do, its not easy...

I do appreciate the feedback on the +-2% that would probably work out best. As far as the resistor deal... this is what is actually going on behind the scenes (I will try to keep this as simplistic as possible):The knobs you are turning are called potentiometers, that function by varying resistance... Now don't get to far ahead of me here... I am not running your air flow signal through these resistors, my computer checks the value of the resistance of these knobs and thus knows what you are intending to do. This means the computer knows what you want and that value is a solid REAL DIGITAL value that the computer can then use in its data manipulation to change the output air flow value. The reason I can't have tons and tons of these knobs is because A) they cost money and time to wire, debug, etc. and B) The computer can only interface with a certain number of them. I may be able to pull off five knobs, if you guys think it would be more beneficial, let me know what RPM ranges you would want.

Keep em coming guys

[C-Kwik]

In concept the idea is good, but realistically only as good as a hacked MAF. It's still only fooling the ECU. When coupled with larger injectors, the ECU will advance timing thinking the motor is not under as much load, despite the fact it might be under more load. Too large an injector will advance timing quite a bit.

Couple of ideas. It may involve some research on your part, but see if both the KA and GM MAF's use a linear airflow curve(Voltage vs CFM cuve would be a straight line on a graph). If that's the case, you can probably get away with one knob to simplify things and just make it adjust the signal the same across the entire airflow range. Secondly, perhaps add a timing adjustment feature. Perhaps boost dependent and/or it can adjust it on a curved slope of some sort. With my E-Manage, I only needed a small amount of adjustment at higher boost and loads and I made no changes to the fuel map other than to use the injector correction feature. This only reduces the actual MAF voltage by a set percentage so as long as both MAF's use a linear curve, I would think it will be simple. Of course if you know what you are doing, you can probably make it work this way, but if the two MAF's have differently shaped curvesm then it would likely get really complicated.

I think it's great of you to try and do this and wish you the best of luck.

[j-z]

this does sound like a good idea. i think 5 different rpm level adjustments would be more logical than 3 (just to allow for more fine tunning to squueze out every bit of power you can) and in +- 2% increments. your pricing does seem pretty reasonable too. 150 is way to damn low for something this guy is gonna pull off.

[DSMs_Suck]

Thanks for the encouragement.

I have a program already written up that will interface the microcontroler to my laptop and give me datalogged readings from the GM Maf and the stock KA MAF. From there I will perform all the needed analysis to get the curves to line up. If they are linear (which I would assume they be they will be) easy enough. If not, I will perform a some form of a regression to get them to fit.. Its not the worst in the world, again we are talking about a 50 MHz standalone chip running all this, with compatibility for pretty advanced mathematical functions. So basically even if the curves are differently shaped I have it covered. Trust me on this, its not a "let's try this" operation, this is what I focus on in school, what I do for hobby, and what I will do for a living in about a year. I also have experience with tuning for about 5 years now and have tuned on loggers + AFC, other AFC devices, "link" style standalones, AEM EMS', and even haltech/tec.

As far as the timing issue goes, overall I think it's not as big of a deal as people make it out to be. This setup would be no different than ANY metering system that lowers the MAF reading to compensate for larger injectors. In my opinion if you are going with a 370 lets say, push back your base timing about 2-3 degrees, if you are going with 550s knock it back 5-6.

Also look at what all vehicles have accomplished with the typical MAS + Injector + AFC setup. TONS of people have doubled stock horsepower with no issues what so ever. I have seen DSMs go 10s with that, GNs put down over 600 with a translator type setup, Supras ran VPC + GCC to well over 600 horse. Honda boys always go with mitsu 450s and an AFC and you know the internals on most of those are like a damn tin can.

Murray

[DSMs_Suck]

this does sound like a good idea. i think 5 different rpm level adjustments would be more logical than 3 (just to allow for more fine tunning to squueze out every bit of power you can) and in +- 2% increments. your pricing does seem pretty reasonable too. 150 is way to damn low for something this guy is gonna pull off.

Thanks for the support man!I agree I am going to see if I can pull it off with 5 knobs. the +-2% definately seems like the best path. Any ideas on which RPM ranges you want for each knobs? This was my idea:0-15001501-30003001-45004501-55005500-UP

Murray

[MikeMurphy]

Your enthusiasm is promising. Im looking forward to the finished product!

[aleph1]

It seems like a good idea, but you are forgetting that the JWT ECU also tunes timing as well as removal of limiters, so its not really comparable. Secondly, the whole GM MAF translator is a good idea and all, but for ~350 bucks for (basically) a bigger MAF and a way stripped down AFC. Its just not worth it to me. Id rather just buy a Z32 maf (im sure could be found for 100 bucks, although 150 is avg) and HKS SAFR (roughly 200 shipped). I am excited to see how this comes out though.

Im not trying to tell you your product is not good, cuz its cool. BUT If I had the money for either your MAF or the previous setup I mentioned...I would rather buy my setup. Similar MAF size and flow and a FAR better computer controlling its functions. Im just trying to be honest. To me your product is just too "middle of the road" so to speak, the fuel functions it provides are basic at best and I believe that many people will just end up getting an AFC or what not later to fine tune it anyway...although once the testing comes out, Ill be the first to eat crow if and when you prove me wrong =)

[MarkEmark]

I like the idea a lot, and I wish you the best of luck.

Not everyone wants to go the S-AFC route; the adjustability/complexity of the S-AFC is quite intimidating, and scares people like me who don't like tinkering with something that has the power to easily cause catastrophic engine damage if done uncorrectly. Not everyone needs the tuneability of the S-AFC, especially when an adjustable FPR works rather adequately to adjust a/f ratios.

JWT's do adjust timing, but everyone who doesn't have a JWT and boosts their KA's never have problem with just adjusting (retarding) the timing manually.

I know if I didn't just drop $450 in the JWT ECU (bought it for $350 off of ebay, had it re-tuned for $100), this route would seem very appealing. I'm sure after you get it all sorted out you could probably drop the price maybe to $300, and then the product would be all the more appealing.

Good luck!

[TopStreet240]

Murray, are you looking for a test car that you can do this on, I see you live in the Milwaukee Area, perhaps we could meet up at a local shop and talk more.

[Redline240]

but for ~350 bucks for (basically) a bigger MAF and a way stripped down AFC. Its just not worth it to me. Id rather just buy a Z32 maf (im sure could be found for 100 bucks, although 150 is avg) and HKS SAFR (roughly 200 shipped).

Or for even cheaper you could hack the stock MAF and get the HKS AFR and bingo you got a 3in MAF and a afc for 200...don't see the value in it...

Redline

[racin-type]

Would it be hard to incorporate a retard timing feature based on boost? Even an automatic retard where the user doesn't have to do anything to make it simple.

Even without timing controls this device is very interesting for me. Not everyone owns an S14 where the hack maf is done on and I haven't heard one person that has done it on the S13 maf. Some people mention that a upgrade maf/SAFC can be had for roughly the same price, but people like me, I don't want to buy used when i don't have to.

But i do think a round figure like $300 would be a better price. Maybe use a less advanced processor than your 50mhz, from what you are saying its overboard already.

[DSMs_Suck]

HKS AFR doesnt even control +-X% that my setup would.. The GM 3" would make the hacked maf look like a joke.

There is another option that you guys can have if its a big deal but this I need input on. I can make the SAFC (and comperable devices) look stupid if you want to attach a laptop to my box. I could have your 14 points of adjustment or whatever you want and you would interface the box to the computer via a serial line. On the laptop there would be a program that you could enter in the correction vs. (X point RPM) AS well as an overall global setting. Maybe even throw in some monitoring such as RPM, Air Flow, and Correction. However this would mean that you would need to have a laptop and for simplicity sake I figured I would stick with the knobs. Knobs and the Serial line is a bit of a stretch but may be possible.

Would this be more appealing?

Murray

[Redline240]

I don't see why the GM one makes the hacked one look like a joke, but anyway...and yes having it at 14 points and a serial port for my laptop would make it much more apealing...

Redline

[240_2NR]

where i live there is 2 dsm's that have the GM MAF and translator one of them owned his own shop the other is my brother in law the dude that owned his own shop has 400whp and is selling most of his set up to my in law because he's aiming for 650hpI just thought u guys should know

[240_2NR]

oh yeah i forgotthey sell the GM maf translators on ebay for like 100 to 200 bucks

[DSMs_Suck]

They sell the MAF Translator for the DSM, its a karman HZ signal, go ahead put it on the 240 and I would love to see it run By the way the MAFT for the DSM is 200 new... Without a sensor.

My setup would be far more indepth, especially with the laptop control, for a new controller that has more adjustment points (DSMs MAFT only has 3) and in the end it would be about the same price.

Again, if I was promised the amount of sales the DSM one made (over 1000) I could get discounts from my vendors for the parts and I could probably sell them for that price too. As it stands its for a KA, they would be made in very limited production (what 10-15 people at for now). If my vendors charge me more for parts, then I can't just absorb the cost.

By the way all, I looked up pricing and if I can be guaranteed 10 people I could do $300.... only thing is I would need to make the initial order guaranteed 10 because that is the minimum purchase to get discount pricing for parts.

The reason the GM would make the hacked MAF look like a joke, is simply because the GM sensor was designed that way. where as you are taking a piece of your old sensor cutting out extra area or placing area where there was none and attempting to tune it out. When GM made the design they took into account air flow characteristics, etc, etc, they are a multimillion dollar company that pays big bucks to get a good design.. Thats why that sensor is on TONS and TONS and TONS of GM vehicles.... Proven, reliable and very accurate. Not a "hack"

[aleph1]

Or for even cheaper you could hack the stock MAF and get the HKS AFR and bingo you got a 3in MAF and a afc for 200...don't see the value in it...

Redline

Some people have S13 DOHC which = non hackable.

If this product had the computer attachment, that would be awesome. It changes everything. You have to understand that for the price you are asking, a lot of KAT electrical setups are cheaper and, pretty much, equally as good (eg hack MAF). Hacking the MAF may seem ghetto or what not, but its proven around here. Orion for instance has had very good results with it. Of course it only works on S14s and S13 SOHC...which leaves me and the rest of the S13 DOHC out in the cold on that...

In short, I think I would pay 300 for it if it had the computer attatchment...I dont really care about the knobs. Getting a laptop is easy so its no big deal I would think. Im sure you guys have friends that can lend it to you or you can just buy an old one for like 100 bucks, just fast enough to run the simple prog. OR even better, If it could log the specs you mentioned, then you could detach it and hook it up to your desktop, review the logs, and reprogram it....that would be cool. Not sure if possible with power requirements...

[spitz7985]

I would pay $300 if you (Murray) will help me tune it. I live close to Top Street.

I would prefer knobs for now, but it would be nice if there was like a stage 2 upgrade that allowed a laptop to be connected. A datalogging feature would be awesome.

[BuddhistWitch]

Hell, I would buy it for 300. And yeah, most of us do have access to a laptop, so would you be able to have it where there are knobs, and for a laptop, or would that not work out.

But I like spitz's idea of an upgrade for the laptop, not all of us are shooting for super-high hp and need all that fine-tuning.

And yes, unfortunately for me, I own a 93, so I can't hack the MAF either, this is a godsend, stop pounding on the guy.