I was just thinking some things over in my head. The MAFs for our cars are restrictive and max out way to early. So I was thinking about the hacked MAF thing again, I know I can build dome, thats the easy part. But what I was thinking was getting another MAF from a different vehicle, or a custom MAF that uses the same voltage(0.0 to .5MV's right?) and swapping injectors in and out till I figure out which runs best with what. That way we can avoid the whole JWT retune.
WD
Custom MAF Research
But you would have issues with the VQ map no being able to make the voltage curve linear... low boost/low HP I guess that wouldn't be an issue (maybe) but with higher boost you really would be pushing it.
Instead, if you use the hacked MAF idea, maybe by constructing a bigger pipe using the SAME element as the stock MAF then the VQ map would still be able to make the V curve linear. The thing is really constructing a good pipe to mount the element.
Instead, if you use the hacked MAF idea, maybe by constructing a bigger pipe using the SAME element as the stock MAF then the VQ map would still be able to make the V curve linear. The thing is really constructing a good pipe to mount the element.
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MikeMurphy
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I dont see why it wouldnt work. Allow more flow, thus the element will only cover a portion of the flow area, and just grab some fuel correction of some sorts to slide the whole fuel map over a bit and call it a day. I dont know how accurate the reads are though at low voltages to maintain the 5V, for idling.
whats the diameter on the stock KA maf anyhow?
whats the diameter on the stock KA maf anyhow?
You really need to build a flow bench.A couple of squirrel cage blowers and something to remove the turbulence before the MAF and and an anemometer (wind speed measurer). If you know the flow rate and the volume and temperature you can caluclate the mass of air. Make a bunch of measurements of the stock MAF and start hacking until you get what you want.Link on Anemimeters: http://clcgi.msu.edu/~rtsmith/anemomet.html
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I am Technoman
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I say we look real hard into finding a MAP sensor setup and to hell with a MAF! I doubt we can just find one that will work but maybe with some help like from JWT because they have all the secrets to Nissans ECU’s they can give us some help on how the ECU see’s voltage and maybe they can suggest a new program. Or a map sensor that would work with a Nissan ECU. NOT!!!!!!!:D
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C-Kwik
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The problem is the injector drivers may not be able to handle too large an injector. Too short an injector pulse signal may not yield the correct injector pulse. It can be somewhat similar to the problem with getting too close to 100% duty cycle. The largest injectors JWT runs currently are 72 lb injectors. Not sure if this is a limitation due to the injector driver.
Secondly, at too low a MAF signal, the ECU may not be able to compensate and/or may adversely affect the ignition timing too much. Low MAF signals tend to tell the ECU to advance timing since the ECU will think there is a lighter load. Depends on th type of ECU. This has been discussed quite a bit in the E-Manage mailing list. Noone could confirm in my scan of emails on that list if Nissan ECU's do this or not. But I usually only look for particular types of posts there or I just delete them. I know Orion has backed off his timing about 3 degrees while using his hacked MAF. I have my E-Manage timing backed off at higher MAF readings. I still get some light ping occasionally on hot days, but I think it might be because my MAF is maxed under full load. I'll see what happens once I upgrade to a Z32 MAF.
Secondly, at too low a MAF signal, the ECU may not be able to compensate and/or may adversely affect the ignition timing too much. Low MAF signals tend to tell the ECU to advance timing since the ECU will think there is a lighter load. Depends on th type of ECU. This has been discussed quite a bit in the E-Manage mailing list. Noone could confirm in my scan of emails on that list if Nissan ECU's do this or not. But I usually only look for particular types of posts there or I just delete them. I know Orion has backed off his timing about 3 degrees while using his hacked MAF. I have my E-Manage timing backed off at higher MAF readings. I still get some light ping occasionally on hot days, but I think it might be because my MAF is maxed under full load. I'll see what happens once I upgrade to a Z32 MAF.