AFPR usefull or useless
I replaced my stock FPR w/ an adjustable one and I SWEAR it fixed some of my fuel economy issues. I was getting 13 mpg with the 6 speed, changed only the regulator and started knocking out 17 and 18 mpg tanks. All this with mods in the sig. Now I'm running non-lockup auto and I'm back to my 13 mpg and less tanks! I have no clue as to why my regulator change gave me such a bump in economy cuz the old one was keeping pressure. Could the bypass inside the stocker have been malfunctioning?
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From: The beautiful Kingdom of Bahrain
Originally Posted by dhdenney
I replaced my stock FPR w/ an adjustable one and I SWEAR it fixed some of my fuel economy issues. I was getting 13 mpg with the 6 speed, changed only the regulator and started knocking out 17 and 18 mpg tanks. All this with mods in the sig. Now I'm running non-lockup auto and I'm back to my 13 mpg and less tanks! I have no clue as to why my regulator change gave me such a bump in economy cuz the old one was keeping pressure. Could the bypass inside the stocker have been malfunctioning?
That's the only thing I can figure out. I didn't tear the FPR down or anything to examine. I did not try to tune my engine by the regulator. I set the pressure to 43.5 psi with the vacuum line off and called it day on the regulator.
A regulator should be considered a fuel system component NOT a tuning tool. You tune with it and you mess with the whole fuel curve rather than just the parts that need it. If you lean it out with the regulator the pcm will learn it at part throttle and over time negate what you did by just holding the injectors open longer unless your tuning has a BLM blocker in it in which case make the tuning right.
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From: The beautiful Kingdom of Bahrain
Originally Posted by 96capricemgr
A regulator should be considered a fuel system component NOT a tuning tool. You tune with it and you mess with the whole fuel curve rather than just the parts that need it. If you lean it out with the regulator the pcm will learn it at part throttle and over time negate what you did by just holding the injectors open longer unless your tuning has a BLM blocker in it in which case make the tuning right.
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If you study what some people say, they try and sell you a regulator and tell you to bump down the pressure. It's pretty simple why. The stock tables for WOT PE mode are super super rich. Lowering pressure will lean you out and make more power. But it's a highly inaccurate way to do it, especially when you start adding mods.
Originally Posted by HBHRacing
If you study what some people say, they try and sell you a regulator and tell you to bump down the pressure. It's pretty simple why. The stock tables for WOT PE mode are super super rich. Lowering pressure will lean you out and make more power. But it's a highly inaccurate way to do it, especially when you start adding mods.
With stock tuning, it won't make mre power very long. It skews the long term fuel trims, same as a hacked up MAF. Drive it a few miles in closed loop, and after it "learns" the corrected fuel trims, it will add that % of fuel at WOT and any gains are gone. I always recommend a stock regulator. One less thing they can screw up.
All that said I put an adjustable on my car today I( am trying to make the injectors I have work better though. They were designed for higher pressure and I was maxxing them out, went the regulator route because a friend was getting rid of one and I had some spare parts he could use.
I am turning the pressure up and then will keep playing with the injector sizing in the programming until I get it dialed in again just right. There are calculators available online to help figure out what pressure changes do to injector ratings that is what I am doing to get it close first.
Before this swap my fueling was good up uintil the very top of each gear when the injectors would be 97%+ Duty Cycle at which point they don't fully close and things got rich this is also hard on the injectors, what I am doing is using it to make the injectors act larger not tuning. This is not a good idea with all injectors because for instance stock injectors can lock closed if overpressured, what I am using are 32lbs LS1 injectors which are 28lbs at stock LT1 pressure, I am going to push the regulator up to the 58psi they were originally rated at to run them as 32lbs.. There is a real likelyhood in the future I will just buy larger injectors with some current home repairs going on I took this solution that allowed me to not spend a dime just got some spare parts out of the garage. Guess what I am saying is sort of "do as I say not as I do" or at least understand I am using it as a component not a tool.
I am turning the pressure up and then will keep playing with the injector sizing in the programming until I get it dialed in again just right. There are calculators available online to help figure out what pressure changes do to injector ratings that is what I am doing to get it close first.
Before this swap my fueling was good up uintil the very top of each gear when the injectors would be 97%+ Duty Cycle at which point they don't fully close and things got rich this is also hard on the injectors, what I am doing is using it to make the injectors act larger not tuning. This is not a good idea with all injectors because for instance stock injectors can lock closed if overpressured, what I am using are 32lbs LS1 injectors which are 28lbs at stock LT1 pressure, I am going to push the regulator up to the 58psi they were originally rated at to run them as 32lbs.. There is a real likelyhood in the future I will just buy larger injectors with some current home repairs going on I took this solution that allowed me to not spend a dime just got some spare parts out of the garage. Guess what I am saying is sort of "do as I say not as I do" or at least understand I am using it as a component not a tool.
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From: Charlotte, NC
Originally Posted by 96capricemgr
All that said I put an adjustable on my car today I( am trying to make the injectors I have work better though. They were designed for higher pressure and I was maxxing them out, went the regulator route because a friend was getting rid of one and I had some spare parts he could use.
I am turning the pressure up and then will keep playing with the injector sizing in the programming until I get it dialed in again just right. There are calculators available online to help figure out what pressure changes do to injector ratings that is what I am doing to get it close first.
Before this swap my fueling was good up uintil the very top of each gear when the injectors would be 97%+ Duty Cycle at which point they don't fully close and things got rich this is also hard on the injectors, what I am doing is using it to make the injectors act larger not tuning. This is not a good idea with all injectors because for instance stock injectors can lock closed if overpressured, what I am using are 32lbs LS1 injectors which are 28lbs at stock LT1 pressure, I am going to push the regulator up to the 58psi they were originally rated at to run them as 32lbs.. There is a real likelyhood in the future I will just buy larger injectors with some current home repairs going on I took this solution that allowed me to not spend a dime just got some spare parts out of the garage. Guess what I am saying is sort of "do as I say not as I do" or at least understand I am using it as a component not a tool.
I am turning the pressure up and then will keep playing with the injector sizing in the programming until I get it dialed in again just right. There are calculators available online to help figure out what pressure changes do to injector ratings that is what I am doing to get it close first.
Before this swap my fueling was good up uintil the very top of each gear when the injectors would be 97%+ Duty Cycle at which point they don't fully close and things got rich this is also hard on the injectors, what I am doing is using it to make the injectors act larger not tuning. This is not a good idea with all injectors because for instance stock injectors can lock closed if overpressured, what I am using are 32lbs LS1 injectors which are 28lbs at stock LT1 pressure, I am going to push the regulator up to the 58psi they were originally rated at to run them as 32lbs.. There is a real likelyhood in the future I will just buy larger injectors with some current home repairs going on I took this solution that allowed me to not spend a dime just got some spare parts out of the garage. Guess what I am saying is sort of "do as I say not as I do" or at least understand I am using it as a component not a tool.
Just remember, not everyone knows what they are doing. I have seen many, many people bump pressure up to 60 PSI on stock injectors to fatten them up. They don't realize that it doesn't work and will load up the injector. It's just a very wise idea to run the math on what injector your needing and still use stock regulator. Makes it a heck of a lot more simple on the tuner as well.
and rememeber if you lock up a stock injector it locks closed not open.
Since we're on the topic of fuel pressures. What ideally should fuel pressure be AT WOT/vacuum off regulator??
Since we're on the topic of fuel pressures. What ideally should fuel pressure be AT WOT/vacuum off regulator??
Yes that is why I tried for the extra long detailed post. I would never do this to stock LT1 injectors but the LS1 injectors I am running were designed for 58psi. I have the tuning stuff though I have Jeff at CAM do most of the tuning. For this I will be playing with the injector sizing in the tuning till the BLMs and WOT AFR are the same as they were before.
I think even those of you who think am an *** will agree I have a higher than average knowledge level, hence the "do as I say not as I do" comment, because yeah most people would just cause problems with an adjustable regulator.
I think even those of you who think am an *** will agree I have a higher than average knowledge level, hence the "do as I say not as I do" comment, because yeah most people would just cause problems with an adjustable regulator.