ECU learning capabilities?
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I am working on a low boost turbo system for my car and, at least in the beginning, am not completely convinced that I need a standalone or any other ecu programming device. Of course that presumption could change the first time I fire it up.
Yes, if I were trying for 8 psi I know I would absolutely, positively need something, but from everything I can read and from some past experiences I know that I can control the A/F ratio pretty closely by using a rising rate fuel pressure regulator.
Based upon all the people running stock injectors I know they will handle the fuel requirements of 5-6 psi.
Whether I increase the amount of fuel with injector width or fuel pressure I get the same effect. Yes, I understand that if I go too far on fuel pressures I will load up the injectors and they will have a hard time responding quickly &/or overheat, but past experiences and responses from other lists on other cars says it is done with regularity.
One big plus for a RRFPR is the fact that I think it will "trick" the ecu into not "unlearning" the performance. Many people have had to pull the ecu memory fuse to get back to factory defaults or the performance degrades as the computer looks at short term and long term fuel trim and variations from it's programmed norms in closed loop and tries to compensate or pulls a CEL.
(WOT is simpler as it is only trying to match a pressure to get a certain A/F ratio since WOT uses a map. Closed loop seems to be the trouble area.)
If I need to run more pressure than is good for the injectors I think I have found a source for larger Honda Specific injectors that won't require a new fuel rail. To keep a good idle I could reduce fuel pressure. I will post more on these injectors when I finally get one in my hand that I can compare.
Everything in my thought process is predicated upon the fact that the ecu doesn't look at fuel pressure. Does anyone know if that is a fact?
Spark is something that I know needs help and at the moment the 4 channel J&S Safeguard seems to hold the most promise. J&S is currently looking for a volunteer in SoCal for a cut rate install so that he can do a write up on install and any specific tuning issues. I only wish I were in SoCal.
See this link: https://www.s2ki.com/forums/showthread.php?...threadid=132857
Of course there's always Plan B, which involves spending $$$ and, more importantly, lots of time that I don't have, but I will go there if I have to. I thought I would try the simple solution first.
Yes, if I were trying for 8 psi I know I would absolutely, positively need something, but from everything I can read and from some past experiences I know that I can control the A/F ratio pretty closely by using a rising rate fuel pressure regulator.
Based upon all the people running stock injectors I know they will handle the fuel requirements of 5-6 psi.
Whether I increase the amount of fuel with injector width or fuel pressure I get the same effect. Yes, I understand that if I go too far on fuel pressures I will load up the injectors and they will have a hard time responding quickly &/or overheat, but past experiences and responses from other lists on other cars says it is done with regularity.
One big plus for a RRFPR is the fact that I think it will "trick" the ecu into not "unlearning" the performance. Many people have had to pull the ecu memory fuse to get back to factory defaults or the performance degrades as the computer looks at short term and long term fuel trim and variations from it's programmed norms in closed loop and tries to compensate or pulls a CEL.
(WOT is simpler as it is only trying to match a pressure to get a certain A/F ratio since WOT uses a map. Closed loop seems to be the trouble area.)
If I need to run more pressure than is good for the injectors I think I have found a source for larger Honda Specific injectors that won't require a new fuel rail. To keep a good idle I could reduce fuel pressure. I will post more on these injectors when I finally get one in my hand that I can compare.
Everything in my thought process is predicated upon the fact that the ecu doesn't look at fuel pressure. Does anyone know if that is a fact?
Spark is something that I know needs help and at the moment the 4 channel J&S Safeguard seems to hold the most promise. J&S is currently looking for a volunteer in SoCal for a cut rate install so that he can do a write up on install and any specific tuning issues. I only wish I were in SoCal.
See this link: https://www.s2ki.com/forums/showthread.php?...threadid=132857
Of course there's always Plan B, which involves spending $$$ and, more importantly, lots of time that I don't have, but I will go there if I have to. I thought I would try the simple solution first.
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Terry runs the Vortech 10:1 unit but says it tops out at 5 psi which would be alright with me for a while.
Maybe after I get bored with that there will be a fuel control system that seems to work for everbody and requires minimal work to install and get running.
On his website I don't see that Terry uses any spark control so maybe that is why 5 psi is the limit. I have PM'd him for more info.
He also says throttle response is not as good as a with a programmable unit. I'm not sure what that means unless it is tip in problems which seem to be a problem with every aftermarket unit I have seen or heard about on any car.
Maybe after I get bored with that there will be a fuel control system that seems to work for everbody and requires minimal work to install and get running.
On his website I don't see that Terry uses any spark control so maybe that is why 5 psi is the limit. I have PM'd him for more info.
He also says throttle response is not as good as a with a programmable unit. I'm not sure what that means unless it is tip in problems which seem to be a problem with every aftermarket unit I have seen or heard about on any car.
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I have just spent some time with some Miata people who use an FMU on Greddy units. They claim that they have gotten back most of the throttle tip in response simply by upping the baseline (not idle) fuel pressure.
What they call baseline we would probably call WOT. They simply up the pressure at no vacuum from the stock 42 to 50 psi. They say that since the FMU is reacting to events after the fact they are building in an "anticipation" factor and although it is still not as crisp as with a Link it is much better.
What they call baseline we would probably call WOT. They simply up the pressure at no vacuum from the stock 42 to 50 psi. They say that since the FMU is reacting to events after the fact they are building in an "anticipation" factor and although it is still not as crisp as with a Link it is much better.
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