what happens if you push 20psi on a 2bar map tune. I know that the 2 bar is only good for 14.7psi, but what would the computer do? Will the motor be ok running 20psi? I remember I use to do it with my ty, but I don't remember what the ECM would do. The reason I ask is, I want to tune my silverado with a 2 bar map. (Speed density tune.)( Its MAF now) I know that I could run a 3 bar but I am just wondering what will happen with the tune on a 2 bar? Its been awhile since I played with ty's or sy's and I forget what happens with SD tune. Thanks Bryan.
20lbs on a 2 bar map.
- Thread starter bryan
- Start date
It's just a six
Super Member
Re: 20lbs on a 2 bar map.
My air/fuel ratio was fine w/18 lbs of boost w/a Pittbull chip, ECM still works,just mainly make sure your a/f ratio is ok & watch the knock retard.
My air/fuel ratio was fine w/18 lbs of boost w/a Pittbull chip, ECM still works,just mainly make sure your a/f ratio is ok & watch the knock retard.
jwaller
Evil Genius/SyTy Guru
Re: 20lbs on a 2 bar map.
if the overboost flag has been turned off and you have enough fuel pressure not to run lean it works just fine. thats the only way you could run more than 14.7 in the old days before 3 bar chips came along. only thing is all you have to tune with is fuel pressure. and as long as you have rock solid boost control is works pertty good.
if the overboost flag has been turned off and you have enough fuel pressure not to run lean it works just fine. thats the only way you could run more than 14.7 in the old days before 3 bar chips came along. only thing is all you have to tune with is fuel pressure. and as long as you have rock solid boost control is works pertty good.
autoaddictions
Active member
Re: 20lbs on a 2 bar map.
Id be carefull with that I blew my motor today !! Using a pittbull strip chip 19psi 2 bar map
My truck still runs but it lays down bad at 12psi and wont make any more. Sounds like rod knock. My wide band afrs where 12.0 to 12.5 must of knocked some thow. IM Pissed.
Now im looking at a rebuild with only 35,000 on the clock. Dont think ill be using that chip or a 2 bar again!!
jwaller said:
Id be carefull with that I blew my motor today !! Using a pittbull strip chip 19psi 2 bar map
My truck still runs but it lays down bad at 12psi and wont make any more. Sounds like rod knock. My wide band afrs where 12.0 to 12.5 must of knocked some thow. IM Pissed.
Now im looking at a rebuild with only 35,000 on the clock. Dont think ill be using that chip or a 2 bar again!!
dgoodhue
BuSTeD 4.3
Re: 20lbs on a 2 bar map.
You can run 20psi with a 2 bar map, but it has no way to compensate above 14.5psi or so.
This is what was done, back in the 90's So basically you would have to tune for fueling at 20 psi at 14.5 psi portion of the VE table, but it would be really rich for fueling around 15 psi in order to fuel for 20 psi. (or it will be really lean at 20 psi for 14.5 psi fueling) The ECM has no way to control boost above 14.5 psi unless it set to open loop (like ATR Pitbull) and it just approximates a duty cycle and boost would fined tuned with the wastegate rod length. You could also use a boost controller, but it your using the stock turbo it often spikes because of poor boost control and can ruin your motor... You really have to be on top of tuning via scan tool to make sure this is working properly and it will always have its limitations. All of the 2 bar chips are no where near as fined as the 3 bar chips as well.
Anyways this is an archaic way to do this, spend the money on a 3 bar set up, this is crude way to compensate and risked ruining your motor.
You can run 20psi with a 2 bar map, but it has no way to compensate above 14.5psi or so.
This is what was done, back in the 90's So basically you would have to tune for fueling at 20 psi at 14.5 psi portion of the VE table, but it would be really rich for fueling around 15 psi in order to fuel for 20 psi. (or it will be really lean at 20 psi for 14.5 psi fueling) The ECM has no way to control boost above 14.5 psi unless it set to open loop (like ATR Pitbull) and it just approximates a duty cycle and boost would fined tuned with the wastegate rod length. You could also use a boost controller, but it your using the stock turbo it often spikes because of poor boost control and can ruin your motor... You really have to be on top of tuning via scan tool to make sure this is working properly and it will always have its limitations. All of the 2 bar chips are no where near as fined as the 3 bar chips as well.
Anyways this is an archaic way to do this, spend the money on a 3 bar set up, this is crude way to compensate and risked ruining your motor.
It's just a six
Super Member
Re: 20lbs on a 2 bar map.
Quick question,,, what octane fuel were you running w/the strip chip?autoaddictions said:
Re: 20lbs on a 2 bar map.
Thanks for replying guys. Ok, I think I will just tune for 14.7. I dont plan on going to 20 anymore. I have a 2 hose alky setup from Julio Razor, can I just turn up the meth if I am lean? The alky is running a 3 bar map. I really don't think I am going to boost 20psi any more, that is why I am thinking of going with the 2 bar. I just hooked up a nitrous kit, and will be playing with different jettings. I am thinking about running 12psi boost and a 50-75 shot. I asked this question because I may change my mind later if I dot like the NOS.
Thanks for replying guys. Ok, I think I will just tune for 14.7. I dont plan on going to 20 anymore. I have a 2 hose alky setup from Julio Razor, can I just turn up the meth if I am lean? The alky is running a 3 bar map. I really don't think I am going to boost 20psi any more, that is why I am thinking of going with the 2 bar. I just hooked up a nitrous kit, and will be playing with different jettings. I am thinking about running 12psi boost and a 50-75 shot. I asked this question because I may change my mind later if I dot like the NOS.
Daryl H
Donating Member
Re: 20lbs on a 2 bar map.
Manifold Absolute Pressure sensor is based off of 0 PSI on a standard day of 29.92" of Hg at sea level.
At that time a two bar sensor will read the equivilent of negative 14.7 PSI to positive 14.7 PSI.
As you go up from sea level or the barometric pressure drops you lose the negative range of the MAP sensor and gain on the positive side.
So you can run more than 14.7 PSI up Pikes Peak and have a happy truck but doing the Baja thing in Death Valley at 14.7 PSI would be a bad idea.
Manifold Absolute Pressure sensor is based off of 0 PSI on a standard day of 29.92" of Hg at sea level.
At that time a two bar sensor will read the equivilent of negative 14.7 PSI to positive 14.7 PSI.
As you go up from sea level or the barometric pressure drops you lose the negative range of the MAP sensor and gain on the positive side.
So you can run more than 14.7 PSI up Pikes Peak and have a happy truck but doing the Baja thing in Death Valley at 14.7 PSI would be a bad idea.
opcorn2:
It's just a six
Super Member
Re: 20lbs on a 2 bar map.
Still never answered what octane your running w/the Pitbull strip chip??????
Still never answered what octane your running w/the Pitbull strip chip??????
autoaddictions
Active member
Re: 20lbs on a 2 bar map.
Im so pissed i blew that ****er up!! been shoping short block parts all day!!
4gallons of 93 with one gallon of c16 !!It's just a six said:
Im so pissed i blew that ****er up!! been shoping short block parts all day!!
93TyphoonPacetruck
Member
Re: 20lbs on a 2 bar map.
Holy crap Bryan, with all that money you have in the engine I would make sure to get a stand alone system or something, it has alot of potential. Good luck :tup:
Holy crap Bryan, with all that money you have in the engine I would make sure to get a stand alone system or something, it has alot of potential. Good luck :tup:
Re: 20lbs on a 2 bar map.
Thanks, I'm going to need all the luck I can get. Thanks for replying guys. When I get it tuned I will post dyno #'s here. Just to give you guys alittle more info on the truck I am playing with. It is a 2000 silverado, stock 5.3, 317 heads (droped compresion to 8.7:1), 02 zo6 cam,sts rear mounted turbo gt67, 255lph inline, fmic,42lbs inj, two step, 6 speed, now with 4.11's, meth, ls1 intake,918 springs and caltracs. It's making 629hp and 684tq right now at 20psi. Next steps are 75 shot, kb boost a pump, and only 12psi, with a 2 bar sd tune. I'll post results. Thanks
Thanks, I'm going to need all the luck I can get. Thanks for replying guys. When I get it tuned I will post dyno #'s here. Just to give you guys alittle more info on the truck I am playing with. It is a 2000 silverado, stock 5.3, 317 heads (droped compresion to 8.7:1), 02 zo6 cam,sts rear mounted turbo gt67, 255lph inline, fmic,42lbs inj, two step, 6 speed, now with 4.11's, meth, ls1 intake,918 springs and caltracs. It's making 629hp and 684tq right now at 20psi. Next steps are 75 shot, kb boost a pump, and only 12psi, with a 2 bar sd tune. I'll post results. Thanks
Re: 20lbs on a 2 bar map.
The idea is to see how far the stock block will go, Its surpassed all my expectations so far, I am just turning it up a notch or two! LOL I jus hope it holds together long enough to get one clean run in at the track and then build a 383 out of it. That is the plan.
The idea is to see how far the stock block will go, Its surpassed all my expectations so far, I am just turning it up a notch or two! LOL I jus hope it holds together long enough to get one clean run in at the track and then build a 383 out of it. That is the plan.
UR50SLO
V6+2=LSXCamaro
Re: 20lbs on a 2 bar map.
What are you using for OBD2 edit?
If this is the truck your refering to then the fuel is being based more off the MAF than the MAP kind of like a GN. (in theory)
Two ideas:
Your setup does not need alot of help with a "horsepower" rear gear. Your making enough torque that your actually hurting your et with that high gear in there and throwing away all that torque that the engine can make with the turbo.
I'd get that 4:11 gear out of there fast. Drop to a 3:42 ratio.. your going through the traps in 5th aren't ya? If not.. you will be soon and your out of your powerband with that rear gear anyway.
IF your wide band is at mid 12's your way too lean. Get it down in the 11.5-11.7 range at WOT. Your asking for trouble in the 12s for sure. Look at your plugs.. they'll tell you the story. It's got to have balls of allum. on them. (specs) from detonation
Sounds like a cool setup! :tup:
Wait to put the bottle on it... I think once you change a few things and get some more fuel to it you'll be happy. Once I picked up turbo's I quit filling bottles!
~Scott
What are you using for OBD2 edit?
If this is the truck your refering to then the fuel is being based more off the MAF than the MAP kind of like a GN. (in theory)
Two ideas:
Your setup does not need alot of help with a "horsepower" rear gear. Your making enough torque that your actually hurting your et with that high gear in there and throwing away all that torque that the engine can make with the turbo.
I'd get that 4:11 gear out of there fast. Drop to a 3:42 ratio.. your going through the traps in 5th aren't ya? If not.. you will be soon and your out of your powerband with that rear gear anyway.
IF your wide band is at mid 12's your way too lean. Get it down in the 11.5-11.7 range at WOT. Your asking for trouble in the 12s for sure. Look at your plugs.. they'll tell you the story. It's got to have balls of allum. on them. (specs) from detonation
Sounds like a cool setup! :tup:
Wait to put the bottle on it... I think once you change a few things and get some more fuel to it you'll be happy. Once I picked up turbo's I quit filling bottles!
~Scott