Hahn Racecraft LSJ GT35R Turbo Project PICS RELEASED!
06BLK what are we going to do now brother. 
12-28-2007, 04:35 PM
#204
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One must bear in mind that a MAF sensor reads Mass Air Flow, which is not affected by pressure (density) changes. That's one reason why they are so damned accurate, as they 'see' mass airflow changes that are caused by pressure variations.
There are a couple more advantages to this method:
1. No re-wiring needed, as we have left the MAF in the stock location.
2. As the intake air temp sensor in our MAF location is reading actual intake air temperature delivered to the engine's cylinders (as opposed to ambient temp), it can react accurately to subtle aspects of charge air temperature (which increases with boost pressure) and intercooler performance; changes that would be missed by an ambient sensor. As this reading is used to calculate ignition timing, this is a significant factor. An ambient-only temp sensor is 'blind' to these changes.
There are a couple more advantages to this method:
1. No re-wiring needed, as we have left the MAF in the stock location.
2. As the intake air temp sensor in our MAF location is reading actual intake air temperature delivered to the engine's cylinders (as opposed to ambient temp), it can react accurately to subtle aspects of charge air temperature (which increases with boost pressure) and intercooler performance; changes that would be missed by an ambient sensor. As this reading is used to calculate ignition timing, this is a significant factor. An ambient-only temp sensor is 'blind' to these changes.
I do have another question though, if the MAF is not effected by pressure changes, what causes the MAF to "max out" in some instances?
12-28-2007, 06:17 PM
#206
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You're welcome! What causes the condition you describe is excessive airflow. The MAF outputs a frequency signal that the PCM interprets as airflow in pounds per minute (for instance). The PCM has an upper limit threshold set. Exceed that threshold, and you have 'maxed out' the MAF.
12-28-2007, 11:17 PM
#208
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You're welcome! What causes the condition you describe is excessive airflow. The MAF outputs a frequency signal that the PCM interprets as airflow in pounds per minute (for instance). The PCM has an upper limit threshold set. Exceed that threshold, and you have 'maxed out' the MAF.
lol i was blowing by the maf limits at first, once i re-worked the charge pipe i'm good now, toward its limits but still on the chart.
bill do you guys have any worries on this? if this guy has the ported head he clames(not sure if hes a stock cam)then its possibile, highly unlikely with the oem cam but possibile.
we ran outta maf on DJT's car with the 272's and his holset, stock head.
we dont know yet, none the less my plans are still in motion for "phase 3" of this project, once thats accomplished i have no worries beside fullthrottles car.
**** air flow numbers......
Last edited by 06black; 12-28-2007 at 11:17 PM. Reason: Automerged Doublepost
12-28-2007, 11:27 PM
#209
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G/sec
lol i was blowing by the maf limits at first, once i re-worked the charge pipe i'm good now, toward its limits but still on the chart.
bill do you guys have any worries on this? if this guy has the ported head he clames(not sure if hes a stock cam)then its possibile, highly unlikely with the oem cam but possibile.
we ran outta maf on DJT's car with the 272's and his holset, stock head.
lol i was blowing by the maf limits at first, once i re-worked the charge pipe i'm good now, toward its limits but still on the chart.
bill do you guys have any worries on this? if this guy has the ported head he clames(not sure if hes a stock cam)then its possibile, highly unlikely with the oem cam but possibile.
we ran outta maf on DJT's car with the 272's and his holset, stock head.
12-28-2007, 11:31 PM
#210
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12-29-2007, 12:37 AM
#212
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once your off the chart(past maf freq range) it doesn't matter how much fuel you have to play with, the ECM has no way to calculate for it, it'll use its last value and run from that.
12-29-2007, 12:59 AM
#213
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The extra injectors are controled by an external stand alone unit from what I could gather. Is it poss to use a ls2 maf. and rescale it. Or bigger piping and once again rescale it. OR Maybe I am retarded and none of this makes sence.
12-29-2007, 01:04 AM
#214
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Our PortFueler module controls the additional injectors independently of the ECM. We are not limited by this factor.
Last edited by Hahn RaceCraft; 12-29-2007 at 01:05 AM. Reason: Automerged Doublepost
12-29-2007, 01:06 AM
#216
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With PortFueler, we just don't need to swap MAF's. We can retain the stock MAF and enjoy all the advantages of doing so, but not be limited by it.
12-29-2007, 01:11 AM
#217
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12-29-2007, 01:31 AM
#218
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The PortFueler control module reads RPM and manifold pressure. The module contains its own internal MAP sensor, good to approx. 30 PSI boost. The boost/vacuum signal for this sensor is sourced at the intake manifold.
The internal MAP reading and RPM are used to access values on a two-axis map grid that looks just like a VE table in HPTuners, for instance. Tuning consists of selecting correct values for the different RPM/MAP points on the map grid.
This map grid, in turn, controls the additional injectors. We've shipped hundreds of these systems for other applications, and the feedback is excellent...folks appear to be able to immediately understand and tune the system.
Of course, in our complete turbosystems, the PortFueler maps will be already pre-calibrated. End users can still fine-tune as needed.
12-29-2007, 01:39 AM
#219
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I should explain the system in greater detail.
The PortFueler control module reads RPM and manifold pressure. The module contains its own internal MAP sensor, good to approx. 30 PSI boost. The boost/vacuum signal for this sensor is sourced at the intake manifold.
The internal MAP reading and RPM are used to access values on a two-axis map grid that looks just like a VE table in HPTuners, for instance. Tuning consists of selecting correct values for the different RPM/MAP points on the map grid.
This map grid, in turn, controls the additional injectors. We've shipped hundreds of these systems for other applications, and the feedback is excellent...folks appear to be able to immediately understand and tune the system.
Of course, in our complete turbosystems, the PortFueler maps will be already pre-calibrated. End users can still fine-tune as needed.
The PortFueler control module reads RPM and manifold pressure. The module contains its own internal MAP sensor, good to approx. 30 PSI boost. The boost/vacuum signal for this sensor is sourced at the intake manifold.
The internal MAP reading and RPM are used to access values on a two-axis map grid that looks just like a VE table in HPTuners, for instance. Tuning consists of selecting correct values for the different RPM/MAP points on the map grid.
This map grid, in turn, controls the additional injectors. We've shipped hundreds of these systems for other applications, and the feedback is excellent...folks appear to be able to immediately understand and tune the system.
Of course, in our complete turbosystems, the PortFueler maps will be already pre-calibrated. End users can still fine-tune as needed.
vary simple, and extremely effective.
your not bound by factory ECM's or MAF's, ect and it'll still spray no matter what the boost is as long as your turn on point is below 30psi and you have enough fuel pressure.
vary cool dear sir, vary snazzy indeed.
12-29-2007, 09:23 AM
#220
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best thread.......EVER! finding out that there was a lsj kit by hahn in r&d is the reason i havent gotten one as of thus far....drive on my good, and kind sir........drive on.
12-29-2007, 10:23 AM
#221
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I Can't wait for the release of this kit. Do you think before summer?
12-29-2007, 12:44 PM
#222
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this has no connection to the MAF what so ever.
my point still stands as valid and correct.
also, i think bill had mentioned that he was planing on having the kit out before summer rolls around.
however i am familiar with the needed R&D behind a project like this and if it doesn't make it out till summer or later i wont be suprised nor disappointed.
its always better to release a kit thats a bit late rather then a kit thats unfinished in any regard.
