2 bar SD tune
a MAP sensor is not brain surgery, its a simple calibrated resistor pretty much.. All it does is take a constant 5V input and a ground, and then it outputs a signal 0-5V based on what it is measuring. So a 2 bar MAP sensor when it is sensing 2 bar of pressure will read 5V on the output signal, and 2.5V at 1 bar, and 0V at 0 bar. A 1 bar MAP sensor will read 5V at 1 bar, 2.5V at 1/2 bar, and 0V at 0 bar. And a 3 bar.. yep- you guessed it: 5V at 3 bar, 2.5V at 1.5 bar, and 0V at 0 bar...
Although with 3bar sensor we PROBABLY can add some safety feature for when wastegate goes bad and turbo blows full boost. Like if you have tune to 20psi, make it crazy lean and crazy retarded in the maps where it would be at 22+ psi. Sort of fuel cut
I think some of you are really over complicating this. Use a 2-bar up about 15 psi. Use a 3bar up to around 28psi. Use a 0-5V GM MAP sensor.
The majority of setups are not going to need the extra resolution that a 2.5bar map would give over a 3bar. You have to be trying to squeeze every last 3rwhp out of your 700+rwhp setup.
The majority of setups are not going to need the extra resolution that a 2.5bar map would give over a 3bar. You have to be trying to squeeze every last 3rwhp out of your 700+rwhp setup.
well i hope to get all out of my 1000+ rwhp. not 700.
i was told that with the 2 bar you can tune the fuel curve by ever 250rpm, is this right? and the 3 bar it is every 500 rpm, is this right?
so if those are true. and i want to shift at 6750. then hell i am stuck between 500rpm on a 3 bar.
this is why i am complicating it. sorry. i'm not sorry. i need this **** right.
i was told that with the 2 bar you can tune the fuel curve by ever 250rpm, is this right? and the 3 bar it is every 500 rpm, is this right?
so if those are true. and i want to shift at 6750. then hell i am stuck between 500rpm on a 3 bar.
this is why i am complicating it. sorry. i'm not sorry. i need this **** right.
8 sec potential, 12 sec slip
iTrader: (50)
Joined: Apr 2002
Posts: 4,092
Likes: 2
From: Savannah, GA
If the 2.5 bar MAP sensor you are looking at outputs 0-5V, then I dont see how anything could go wrong with using it. You will lose some resolution if you go to 3 bar because if you break it down, for every 0.1V is representative of 0.87psi on a 3 bar MAP (assuming the specs are a true 300.0 kPa). And for every 0.1V on a 2 bar, that represents 0.58psi.. I don't know how many decimal places the computer reads to, but I'm just using 0.1 as an example... Now if you could find a 2.5 bar that outputs 5V at 21.76psig (boost) then every 0.1V would represent 0.725psi.
10 Second Club
Joined: Apr 2002
Posts: 1,755
Likes: 2
From: Cincinnati, Ohio
If I understand this right, I was told that if you use a 2 bar MAP and you exceed 1 bar pressure that the car will continue to use the last cell in the VE table that it hit at appr. 15 lbs. boost. So it would probably be O.K. to slightly exceed 15 lbs. because that number will be close enough for most cases if the car should slightly exceed 15 lbs. (say 18 lbs. for instance). I was in the gray area expecting 18 lbs. and was talked out of a three bar by the tuning expert that sold me EFIlive to gain better resolution. I did tune using a 2 bar which did work O.K. for me.
If the 2.5 bar MAP sensor you are looking at outputs 0-5V, then I dont see how anything could go wrong with using it. You will lose some resolution if you go to 3 bar because if you break it down, for every 0.1V is representative of 0.87psi on a 3 bar MAP (assuming the specs are a true 300.0 kPa). And for every 0.1V on a 2 bar, that represents 0.58psi.. I don't know how many decimal places the computer reads to, but I'm just using 0.1 as an example... Now if you could find a 2.5 bar that outputs 5V at 21.76psig (boost) then every 0.1V would represent 0.725psi.
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Verdad Gallardo 8 sec potential, 12 sec slip
iTrader: (50)
Joined: Apr 2002
Posts: 4,092
Likes: 2
From: Savannah, GA
The E40 is the computer from the newer gen 4 engines.. I dont know why it only works on it.. Maybe they only use a 0-1V signal output, or a 0-10V output signal?? I have no clue man.. ask HP tuners. I'm sure they can explain it..
If I understand this right, I was told that if you use a 2 bar MAP and you exceed 1 bar pressure that the car will continue to use the last cell in the VE table that it hit at appr. 15 lbs. boost. So it would probably be O.K. to slightly exceed 15 lbs. because that number will be close enough for most cases if the car should slightly exceed 15 lbs. (say 18 lbs. for instance). I was in the gray area expecting 18 lbs. and was talked out of a three bar by the tuning expert that sold me EFIlive to gain better resolution. I did tune using a 2 bar which did work O.K. for me.
FormerVendor
Joined: Dec 2001
Posts: 2,444
Likes: 2
From: WWW.SPEEDINC.COM
Ok with HPT
2 bar is 15 to 210kpa 5kpa per cell. 400-8000rpm, 400rpm per cell
3 bar is 15 to 315kpa, 5kpa per cell between 15 and 105kpa, 10kpa per cell between 110 and 315kpa. 400-8000rpm, 400rpm per cell.
If I'm tuning a forced induction car speed density it gets done in 3bar. There is absolutely no advantage to running 2bar as resolution with the 3bar is excellent and can be easily tuned for perfect driveability.
Also for comparison in HPT there are 40 vertical cells and 20 horizontal cells in the VE table.
In BS3 there are 16 vertical cells and 16 horizontal cells in the VE table.
2 bar is 15 to 210kpa 5kpa per cell. 400-8000rpm, 400rpm per cell
3 bar is 15 to 315kpa, 5kpa per cell between 15 and 105kpa, 10kpa per cell between 110 and 315kpa. 400-8000rpm, 400rpm per cell.
If I'm tuning a forced induction car speed density it gets done in 3bar. There is absolutely no advantage to running 2bar as resolution with the 3bar is excellent and can be easily tuned for perfect driveability.
Also for comparison in HPT there are 40 vertical cells and 20 horizontal cells in the VE table.
In BS3 there are 16 vertical cells and 16 horizontal cells in the VE table.
10 Second Club
Joined: Apr 2002
Posts: 1,755
Likes: 2
From: Cincinnati, Ohio
If I understand this right, I was told that if you use a 2 bar MAP and you exceed 1 bar pressure that the car will continue to use the last cell in the VE table that it hit at appr. 15 lbs. boost. So it would probably be O.K. to slightly exceed 15 lbs. because that number will be close enough for most cases if the car should slightly exceed 15 lbs. (say 18 lbs. for instance). I was in the gray area expecting 18 lbs. and was talked out of a three bar by the tuning expert that sold me EFIlive to gain better resolution. I did tune using a 2 bar which did work O.K. for me.
Ok with HPT
2 bar is 15 to 210kpa 5kpa per cell. 400-8000rpm, 400rpm per cell
3 bar is 15 to 315kpa, 5kpa per cell between 15 and 105kpa, 10kpa per cell between 110 and 315kpa. 400-8000rpm, 400rpm per cell.
If I'm tuning a forced induction car speed density it gets done in 3bar. There is absolutely no advantage to running 2bar as resolution with the 3bar is excellent and can be easily tuned for perfect driveability.
Also for comparison in HPT there are 40 vertical cells and 20 horizontal cells in the VE table.
In BS3 there are 16 vertical cells and 16 horizontal cells in the VE table.
2 bar is 15 to 210kpa 5kpa per cell. 400-8000rpm, 400rpm per cell
3 bar is 15 to 315kpa, 5kpa per cell between 15 and 105kpa, 10kpa per cell between 110 and 315kpa. 400-8000rpm, 400rpm per cell.
If I'm tuning a forced induction car speed density it gets done in 3bar. There is absolutely no advantage to running 2bar as resolution with the 3bar is excellent and can be easily tuned for perfect driveability.
Also for comparison in HPT there are 40 vertical cells and 20 horizontal cells in the VE table.
In BS3 there are 16 vertical cells and 16 horizontal cells in the VE table.
BS3 and the other aftermarket engine management systems have other beneficial features that the stock PCM doesn't have such as control for 16+ injectors, low impedence, WB02 direct input, etc.
and bs3 is 3K.
i would love to have 16injectors.
quick question for you BS3 guys. can i use my stock gauges? and does my abs and traction control still work?
