log boost with JDM MAP sensor (updated instructions)
isnt vacuum on the JDM sensor in psi and vacuum on the ZT2 sensors is in inhg or something??
Its all in the scaling.. I know in Mitsulogger its in PSI regardless, most gages do read in inHg under vacuum. I think the ZT2 software and the display, do actually read in inHG.
P(psi) = 0.491130 * P(inHg)
P(inHg) = 2.03602 * P(psi)
I am not very knowledgeable with adding formulas for mitsulogger but could you do it in a way where it could evaluate if x was < 0 y = x*491130 else x since x is psi? Not that it is a huge deal since all i really want it to log is boost.
P(inHg) = 2.03602 * P(psi)
I am not very knowledgeable with adding formulas for mitsulogger but could you do it in a way where it could evaluate if x was < 0 y = x*491130 else x since x is psi? Not that it is a huge deal since all i really want it to log is boost.
Last edited by MR Turco; Oct 1, 2007 at 11:03 AM.
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First off thanks for the great how-to and to everyone that helped to sort all of this out!
Does anyone else in here travel over a wide variety of elevations? I am using this mod with the suggested xml changes to mitsulogger, but I know the data will end up with problems eventually.
Is there any way to replace the static psi value with a dynamic equivalent? Or could the formula be rebuilt using the voltage calculated against the known effective max psi the sensor will read? Or perhaps we could drag in a value from the MAF to help calculate this.
Where I drive the temperature swings from +100 f to -40 f and on road trips I've been everywhere from one coast to the other. It would be really useful to have a tool that didn't need manual intervention.
Does anyone else in here travel over a wide variety of elevations? I am using this mod with the suggested xml changes to mitsulogger, but I know the data will end up with problems eventually.
Is there any way to replace the static psi value with a dynamic equivalent? Or could the formula be rebuilt using the voltage calculated against the known effective max psi the sensor will read? Or perhaps we could drag in a value from the MAF to help calculate this.
Where I drive the temperature swings from +100 f to -40 f and on road trips I've been everywhere from one coast to the other. It would be really useful to have a tool that didn't need manual intervention.
First off thanks for the great how-to and to everyone that helped to sort all of this out!
Does anyone else in here travel over a wide variety of elevations? I am using this mod with the suggested xml changes to mitsulogger, but I know the data will end up with problems eventually.
Is there any way to replace the static psi value with a dynamic equivalent? Or could the formula be rebuilt using the voltage calculated against the known effective max psi the sensor will read? Or perhaps we could drag in a value from the MAF to help calculate this.
Where I drive the temperature swings from +100 f to -40 f and on road trips I've been everywhere from one coast to the other. It would be really useful to have a tool that didn't need manual intervention.
Does anyone else in here travel over a wide variety of elevations? I am using this mod with the suggested xml changes to mitsulogger, but I know the data will end up with problems eventually.
Is there any way to replace the static psi value with a dynamic equivalent? Or could the formula be rebuilt using the voltage calculated against the known effective max psi the sensor will read? Or perhaps we could drag in a value from the MAF to help calculate this.
Where I drive the temperature swings from +100 f to -40 f and on road trips I've been everywhere from one coast to the other. It would be really useful to have a tool that didn't need manual intervention.
If you live at sea level and use 14.7 as your boost adder, so with 20lbs of boost and atmosphere your at 34.7 absolute. When you go to 2000ft. the atmosphere is 13.7. so if if you need 34.7 absolute and atmosphere takes off 13.7, then you need 21.lbs of boost, which is a lbs more then at sea level.
keypoints
- a lbs of boost isnt that much. if you travel between sea level and 2000, set the boost adder to something like 14.2, It would be perfect @ 1000ft, then you only be 0.5 lbs lower @ sea level and 0.5 higher @ 2000. also if you travel between seal level and 2000ft, but are by sea level alot more, then set it to 14.4-.5. you'll be perfect @ 500 and only .2-.3 lower at sea level, etc.
- you really shouldn't try to correct boost when its only .1-.6lbs off. On my correction map, it doesnt start correcting boost till 0.8 off +/-. this still maintains a good curve, gets rid of too much correction and allow some space for elevation changes without sending the correction into a frenzy.
-you may think if you went to say 5000 ft it would probably overboost. It would try, but up there, with the thin air, it wont with your WGDC numbers made at sea level, 1000ft, etc.
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Actually you're dead on. The problem is that I want to use the JDM MAP sensor to manage a hight boost configuration (possibly as high as 28 psi) and with the crazy temp changes I see, I'm concerned my the data I'm logging won't accurately reflect the car's actual boost.
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