Pros and Cons to 2 bar vs. 3 bar map??
for those that use the 2.5 bar sensor, how well does that work with hptuners since they only offer 2 bar and 3 bar os's. im sure the 2.5 will work on the 3 bar os just wont be "accurate" kpa scaling which i guess doesnt matter as long as the table is correct
The duramax has a 3.3 bar sensor with **** for vacuum accuracy since diesels don't need that.
The 2.5 bar sensor works just fine for either 2 or 3 bar operating systems since it's up to you to fill in the appropriate values for the map sensor. Only reason I see to use the 2.5 sensor though over the cobalt ss 2 bar sensor (since it's so much more expensive) is for more boost and that that point you would need a 3 bar OS. The scaling would be accurate with the 3 bar OS it just reads up to 2.5 bar max.
The 2.5 bar sensor works just fine for either 2 or 3 bar operating systems since it's up to you to fill in the appropriate values for the map sensor. Only reason I see to use the 2.5 sensor though over the cobalt ss 2 bar sensor (since it's so much more expensive) is for more boost and that that point you would need a 3 bar OS. The scaling would be accurate with the 3 bar OS it just reads up to 2.5 bar max.
is there no good 3 bar map sensors that are direct replacement on ls6 intakes? Not that i plan on making over 22psi, but if it happened better be safe than sorry.
I thought there was an oem 2.5 map sensor that worked that was much cheaper?
I thought there was an oem 2.5 map sensor that worked that was much cheaper?
The duramax has a 3.3 bar sensor with **** for vacuum accuracy since diesels don't need that.
The 2.5 bar sensor works just fine for either 2 or 3 bar operating systems since it's up to you to fill in the appropriate values for the map sensor. Only reason I see to use the 2.5 sensor though over the cobalt ss 2 bar sensor (since it's so much more expensive) is for more boost and that that point you would need a 3 bar OS. The scaling would be accurate with the 3 bar OS it just reads up to 2.5 bar max.
The 2.5 bar sensor works just fine for either 2 or 3 bar operating systems since it's up to you to fill in the appropriate values for the map sensor. Only reason I see to use the 2.5 sensor though over the cobalt ss 2 bar sensor (since it's so much more expensive) is for more boost and that that point you would need a 3 bar OS. The scaling would be accurate with the 3 bar OS it just reads up to 2.5 bar max.
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Sorry to resurrect this thread, however I brought a 2.5 bar sensor from lpe and my tuner is saying it won't work with the gen 3 controller/computer.
Any more info on this? And do any of you use/have a part number for a plug and play 3 bar sensor?
Thanks guys
Any more info on this? And do any of you use/have a part number for a plug and play 3 bar sensor?
Thanks guys
As long as it's a 0-5V it will work fine. The issue will be that at boost it will display a boost value that isn't accurate(accurate but not scaled properly). At 3 bar in the OS you will actually be getting 2.5 bar. While tuning you look at what cell is referenced by the computer for fueling NOT now much boost you are actually running.
Last edited by Exidous; Dec 28, 2013 at 01:53 PM.
I think I get it... Sort of.
He was talking about how that sensor is for late model cars with configurable OS and boost tables.
And that there is only a 2 bar OS and 3 bar OS, no 2.5.
Then what your basically saying is that you use a 3 bar OS and reference the fuel tables to determine what to set the tune at I guess, not boost?
He was talking about how that sensor is for late model cars with configurable OS and boost tables.
And that there is only a 2 bar OS and 3 bar OS, no 2.5.
Then what your basically saying is that you use a 3 bar OS and reference the fuel tables to determine what to set the tune at I guess, not boost?
VE table ONLY. Fuel injector stuff stays the same.
A 2 Bar or 3 Bar OS can be used. You will get a max of 2.5Bar either way. At vacuum they are the same. At boost the amount of boost per cell is what is different. To it, 5v is 210kPa with a 2Bar OS and 315kPa with a 3Bar OS. The sensor however, reads 5v as 2.5Bar.
HPTuners as an example. As you scan the PID's you are seeing the normal vacuum driving around. Some goof off Mustang comes near and you get into max boost. For simplicity you are running a 2bar with 2.5bar MAP. At WOT (2.5Bar) your PCM registers 210kPa or 2Bar. You change the 210kPa vs RPM cells to make your AFR 11:1 or whatever you are using and beat the crap out of the mustang without blowing up. :-p
What you are technically doing is adjusting the fueling for 2.5Bar even though the cells in the PCM read 2Bar.
A 2 Bar or 3 Bar OS can be used. You will get a max of 2.5Bar either way. At vacuum they are the same. At boost the amount of boost per cell is what is different. To it, 5v is 210kPa with a 2Bar OS and 315kPa with a 3Bar OS. The sensor however, reads 5v as 2.5Bar.
HPTuners as an example. As you scan the PID's you are seeing the normal vacuum driving around. Some goof off Mustang comes near and you get into max boost. For simplicity you are running a 2bar with 2.5bar MAP. At WOT (2.5Bar) your PCM registers 210kPa or 2Bar. You change the 210kPa vs RPM cells to make your AFR 11:1 or whatever you are using and beat the crap out of the mustang without blowing up. :-p
What you are technically doing is adjusting the fueling for 2.5Bar even though the cells in the PCM read 2Bar.
Works just fine, use the 3 bar OS and put in the appropriate linear and offset values and it will read up to 2.5 bar.
Sounds good. Thanks again guys. I sent a message to my tuner, just getting a mail order tune to get the car in a running/drive able state, and hopefully he'll oblige.
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Unless anyone else disagrees with that...?
You could try sucking on the sensor while looking at your laptop, and see if that drops the KPA below 105.
Where does everyone mount their map sensor that's running a Vic Jr? I'm sure there's info on this but I haven't looked, I'm not that far along on my build yet but I have my intake and Aaron's elbow sitting in the garage..
Last edited by BAADGOAT; Dec 29, 2013 at 11:49 PM.