j255c Posted August 20, 2009 Share Posted August 20, 2009 I think its 24.5, but im not positive? I know when i have boost >26 it doesnt go off anymore. Anyone know exactly? Trying to make my pump map still retain a failsafe. 06 TB EVO IX SE stock turbo monster subaru hater Link to comment Share on other sites More sharing options...
yamie700 Posted August 20, 2009 Share Posted August 20, 2009 I'm curious on this as well. I was just tuning WGDC for my 18g, had the limit set at 21.5 and I know during a pull it hit 23psi, fuel cut didn't happen. Good thing I have a boost gauge so I let off, no harm done. Link to comment Share on other sites More sharing options...
mwiener2 Posted August 20, 2009 Share Posted August 20, 2009 your boost gauge and the ECU may have different boost readings depending on conditions and locations. Check your pressure by logging and then adjust the fuel cut accordingly My Mods List (Updated 8/22/17) 2005 Outback FMT Running on Electrons Link to comment Share on other sites More sharing options...
yamie700 Posted August 20, 2009 Share Posted August 20, 2009 My boost gauge is digital, and only reads in 1psi increments. When it read 23 I was logging and the ecu saw 22.75. My fuel cut was set to 21.5. I'm still trying to figure out why fuel cut didn't happen. Link to comment Share on other sites More sharing options...
j255c Posted August 20, 2009 Author Share Posted August 20, 2009 your boost gauge and the ECU may have different boost readings depending on conditions and locations. Check your pressure by logging and then adjust the fuel cut accordingly I know that the ecu and gauge may read differently depending on location and condition. My question is: what is the highest psi the factory fuel cut will work at? I know it doesnt work after a certain amount. Thanks, Jeff 06 TB EVO IX SE stock turbo monster subaru hater Link to comment Share on other sites More sharing options...
mwiener2 Posted August 20, 2009 Share Posted August 20, 2009 i think it's 1.5 or 1.8 bar My Mods List (Updated 8/22/17) 2005 Outback FMT Running on Electrons Link to comment Share on other sites More sharing options...
NSFW Posted August 21, 2009 Share Posted August 21, 2009 IIRC the factory sensor is only accurate up to 23 or so. Have you done some data logging to see what boost range the ECU sees? Link to comment Share on other sites More sharing options...
tommypenguin Posted August 21, 2009 Share Posted August 21, 2009 When I had my green on my map sensor would not read over 25.1psi... Link to comment Share on other sites More sharing options...
Legend Posted August 21, 2009 Share Posted August 21, 2009 My boost gauge is digital, and only reads in 1psi increments. When it read 23 I was logging and the ecu saw 22.75. My fuel cut was set to 21.5. I'm still trying to figure out why fuel cut didn't happen. Fuel cut doesn't happen instantly, even if you exceed the fuel cut boost threshold. Like most other failsafes and CEL's there is a delay built-in. MRP must exceed the threshold before fuel cut and CEL. You must not have exceeded the threshold for the entire delay time. Makes sense since you saw it on your boost gauge. I overboosted past my fuel cut boost threshold once when I began tuning my VF52. I don't have a boost gauge. I was logging at the time. The ecu allowed me to exceed the threshold for a period of time.. It's very evident in the log. I wish I could remember how long the delay is... but it's longer than I would have thought... My '05 LGT My '07 Supercharged Shelby Link to comment Share on other sites More sharing options...
yamie700 Posted August 21, 2009 Share Posted August 21, 2009 Fuel cut doesn't happen instantly, even if you exceed the fuel cut boost threshold. Like most other failsafes and CEL's there is a delay built-in. MRP must exceed the threshold before fuel cut and CEL. You must not have exceeded the threshold for the entire delay time. Makes sense since you saw it on your boost gauge. I overboosted past my fuel cut boost threshold once when I began tuning my VF52. I don't have a boost gauge. I was logging at the time. The ecu allowed me to exceed the threshold for a period of time.. It's very evident in the log. I wish I could remember how long the delay is... but it's longer than I would have thought... That makes sense. Is the delay time adjustable? I don't remember seeing a delay when going through the tables, but I'm still a newb so I might have just missed it. Link to comment Share on other sites More sharing options...
Darkness of Death Posted August 21, 2009 Share Posted August 21, 2009 22.3 PSI cut off of stock map sensor ~ but it will read a little higher from overboost. Link to comment Share on other sites More sharing options...
mwiener2 Posted August 22, 2009 Share Posted August 22, 2009 I think I've seen the delay time in a map once. My Mods List (Updated 8/22/17) 2005 Outback FMT Running on Electrons Link to comment Share on other sites More sharing options...
Darkness of Death Posted August 22, 2009 Share Posted August 22, 2009 this was through accessport tuner, the last time i was getting tuned - i was aiming for 24 psi and the tuner told me in the end, that even if he changed the boost target to 24, it would go down to 22.3 automatically because of the factory limit Link to comment Share on other sites More sharing options...
Infamous1 Posted August 22, 2009 Share Posted August 22, 2009 I think its 24.5, but im not positive? I know when i have boost >26 it doesnt go off anymore. Anyone know exactly? Trying to make my pump map still retain a failsafe. It depends on your atmospheric pressure, at sea level it is about 23.5 psi. The lower you atmospheric pressure the higher the reading. Boost cut can be set at the absolute limit of the MAP sensor's reading capability. At your boost levels you should be running a 3.5 bar sensor. Link to comment Share on other sites More sharing options...
Darkness of Death Posted August 22, 2009 Share Posted August 22, 2009 aem 3.5 bar map sensor ~ Link to comment Share on other sites More sharing options...
j255c Posted August 26, 2009 Author Share Posted August 26, 2009 I knows . I should be doing a lot of things differently at this level. 06 TB EVO IX SE stock turbo monster subaru hater Link to comment Share on other sites More sharing options...
captainhook Posted August 26, 2009 Share Posted August 26, 2009 22.3 PSI cut off of stock map sensor ~ but it will read a little higher from overboost. This is right on, right between 22.3 and 22.5 is where mine cut out. Link to comment Share on other sites More sharing options...
NSFW Posted August 26, 2009 Share Posted August 26, 2009 If I remember right, there's a parameter in the logger definitions that isn't subject to the ~22 psi limit. There's a thread over there that lists all of the parameters with some notes about their quirks... Link to comment Share on other sites More sharing options...
j255c Posted August 26, 2009 Author Share Posted August 26, 2009 if you could find that link that would be great. 06 TB EVO IX SE stock turbo monster subaru hater Link to comment Share on other sites More sharing options...
Infamous1 Posted August 26, 2009 Share Posted August 26, 2009 If I remember right, there's a parameter in the logger definitions that isn't subject to the ~22 psi limit. There's a thread over there that lists all of the parameters with some notes about their quirks... Nope, it is suppose to be MRP 4-byte. However if the MAP sensor cannot read it the ecu can't report it. You sitll need a MAP capable of seeing it. Link to comment Share on other sites More sharing options...
NSFW Posted August 26, 2009 Share Posted August 26, 2009 http://www.romraider.com/forum/topic4271.html Manifold Absolute Pressure (Direct)* (2,4) -> The standard SSM parameter, 'Manifold Absolute Pressure' is limited to about 37 psi absolute (about 22 psig at sea level). This new parameter has no effective limit. Link to comment Share on other sites More sharing options...
Infamous1 Posted August 26, 2009 Share Posted August 26, 2009 http://www.romraider.com/forum/topic4271.html Manifold Absolute Pressure (Direct)* (2,4) -> The standard SSM parameter, 'Manifold Absolute Pressure' is limited to about 37 psi absolute (about 22 psig at sea level). This new parameter has no effective limit. Its limit in combination with the stock MAP sensor is 2.5 bar If you swap it for an AEM 3.5 bar sensor its limit will be 3.5 bar absolute. Link to comment Share on other sites More sharing options...
NSFW Posted August 26, 2009 Share Posted August 26, 2009 I see, thanks. Link to comment Share on other sites More sharing options...
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