problems with miata
07-23-2007, 10:30 AM
#21
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NO. what i said in my previous post was not wrong. to sum it up, a rrfpr is pointless to adjust to a/f ratio when the miata is in closed loop, because the ecu will just try to maintain stoich even though the rrfpr is upping the pressure as you build boost at low rpms.
once the computer goes into open loop mode(at higher rpms), and runs off a fuel map, the increased fuel pressure due to the boost acting on the rrfpr can be used to adjust a/f ratio becuase the computer is not trying to maintain stoich, but is fueling based off of a preset map.
so to tune your a/f ratio with an rrfpr at lower rpms in the first gen miata, you need to have an oxygen sensor clamp!
Talk to olderguy and braineack. I might not be the best at explaining it, but without a different ecu or a piggyback, an rrfpr won't do much for your a/f ratio at lower rpms (while the ecu is in closed loop mode)
p.s. the begi and the vortech are both 'tuneable' the vortech uses different discs to adjust how much fuel pressure increases per pound of boost, while the begi's pressure rise to boost ratio can be adjusted infinitely with the built in adjustment screws on the unit.
Anthony
once the computer goes into open loop mode(at higher rpms), and runs off a fuel map, the increased fuel pressure due to the boost acting on the rrfpr can be used to adjust a/f ratio becuase the computer is not trying to maintain stoich, but is fueling based off of a preset map.
so to tune your a/f ratio with an rrfpr at lower rpms in the first gen miata, you need to have an oxygen sensor clamp!
Talk to olderguy and braineack. I might not be the best at explaining it, but without a different ecu or a piggyback, an rrfpr won't do much for your a/f ratio at lower rpms (while the ecu is in closed loop mode)
p.s. the begi and the vortech are both 'tuneable' the vortech uses different discs to adjust how much fuel pressure increases per pound of boost, while the begi's pressure rise to boost ratio can be adjusted infinitely with the built in adjustment screws on the unit.
Anthony
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07-23-2007, 10:50 AM
#23
if you get a static ratio FMU, there's really not much to "tune".
If you keep the SAFC2, you'll have some level of tuneability by modifying the AFM output voltage that the ECU sees. Now, the FMU works off of pressure while the SAFC2 is reading off of mass so it's not an ideal solution but it'll probably work good enough.
I imagine you could hook up a MAP sensor to the S-AFC and tune by pressure but thats another bag of worms
If you keep the SAFC2, you'll have some level of tuneability by modifying the AFM output voltage that the ECU sees. Now, the FMU works off of pressure while the SAFC2 is reading off of mass so it's not an ideal solution but it'll probably work good enough.
I imagine you could hook up a MAP sensor to the S-AFC and tune by pressure but thats another bag of worms
Last edited by magnamx-5; 07-23-2007 at 11:15 AM.
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07-23-2007, 11:03 AM
#24
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not if you tell the computer you aren't adding fuel. And even not it will still dump in the fuel and the ECU has to deal with it, but that's why you hear about hesistation between vacuum and boost. But never that a FMU won't do anything.
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07-23-2007, 11:54 AM
#28
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idiot may be strong. arrogant perhaps. a trait we share.
I speak from experience--not from what I've read. And I've had like every possible type of fuel management on my car.
Ben
I speak from experience--not from what I've read. And I've had like every possible type of fuel management on my car.
Ben
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07-23-2007, 02:07 PM
#30
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vortec or preferrably BEGi FMU. i didn't need an o2 clamp with the BEGi. if you are going to get one, get the less expensive OLDERGUY o2 clamp. Details the classifieds, in a sticky.
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07-23-2007, 02:11 PM
#31
nah man all you need is a rrfpr realy like the one i offered you the 12-1 is abit agressive but it will do the job just fine. the safc is just fine by all means keep it, but more fuel pressure will help you in boost. I ha dno problem at 12psi with my 1.8's, walboro 255hp, obx rrfpr, and a safc2. The only thing you dont have that i did is the rrfpr. lemme know man 
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07-23-2007, 02:30 PM
#33
I agree he needs the extra fuel pressure but the safc can lean out the top end problem you and many others where strugling with on stock ecu and like i said i noticed a good difference in midrange when used with the 1.8's. It is not as good or robust as MS but it still does the job scot. don't hate on him or confuse him he is having enough of a rough time with this as it is.
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07-23-2007, 02:41 PM
#36
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so, I could have said like Richard is fat and smelly don't listen to him.
and it's not that I'm anti SAFC, it' sjsut that I know the fmu/fp/o2 clamp combo works, and works well.
I dunno much about the safc, so if it can lean out the top-end, then great. but as is, he still needs fuel pressure holmes.
and it's not that I'm anti SAFC, it' sjsut that I know the fmu/fp/o2 clamp combo works, and works well.
I dunno much about the safc, so if it can lean out the top-end, then great. but as is, he still needs fuel pressure holmes.
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07-23-2007, 02:41 PM
#37
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Ben
You are still wrong. And repeating yourself, or just being beligerent, doesn't make you right.
Whoa there fella
. lol i wasn't trying to up the tone at all!
Braineack
not if you tell the computer you aren't adding fuel. And even not it will still dump in the fuel and the ECU has to deal with it, but that's why you hear about hesistation between vacuum and boost. But never that a FMU won't do anything.
I'm not saying the FMU won't do anything in closed loop. The FMU is a means to mechanically raise fuel pressure in our efi return fuel system. What I was trying to say was that in closed loop mode, the ecu tries to compensate for the mechanical clamping of the return line that ups the fuel pressure. So braineack, like you said, a solution is to 'tell the computer you aren't adding fuel' when you're in closed loop. That's why i said about the olderguy 02 clamp.
You are still wrong. And repeating yourself, or just being beligerent, doesn't make you right.
Whoa there fella
. lol i wasn't trying to up the tone at all!Braineack
not if you tell the computer you aren't adding fuel. And even not it will still dump in the fuel and the ECU has to deal with it, but that's why you hear about hesistation between vacuum and boost. But never that a FMU won't do anything.
I'm not saying the FMU won't do anything in closed loop. The FMU is a means to mechanically raise fuel pressure in our efi return fuel system. What I was trying to say was that in closed loop mode, the ecu tries to compensate for the mechanical clamping of the return line that ups the fuel pressure. So braineack, like you said, a solution is to 'tell the computer you aren't adding fuel' when you're in closed loop. That's why i said about the olderguy 02 clamp.
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07-23-2007, 02:48 PM
#38
You are an idiot the afm is tuned for the rate and the fpr helps make the injectors act bigger but i did see some nice gains by leaning mine out abit up top and richening th emidrange with my safc, and 105 psi of FP. The adjustability of the safc does not do alot for driveability without a TPS but it still helps if the driveability is decent and you want more power. 90 miata you can have my 12-1 rrfpr for 55$ shipped if you like lemme know. your 265's wont pull alot of fuel on stock fuel pressure but i already told you that. 265*.9/10.5/.5*4= 182 bhp add another say 40-50 psi of Fuel pressure and you have 364 cc/min at 85 psi *.9/10.5/.5*4= 250 bhp are you folowing me now? also please remember a general rule of 15% drivetrain loss for most miatas.
I agree he needs the extra fuel pressure but the safc can lean out the top end problem you and many others where strugling with on stock ecu and like i said i noticed a good difference in midrange when used with the 1.8's. It is not as good or robust as MS but it still does the job scot. don't hate on him or confuse him he is having enough of a rough time with this as it is.
nah man all you need is a rrfpr realy like the one i offered you the 12-1 is abit agressive but it will do the job just fine. the safc is just fine by all means keep it, but more fuel pressure will help you in boost. I ha dno problem at 12psi with my 1.8's, walboro 255hp, obx rrfpr, and a safc2. The only thing you dont have that i did is the rrfpr. lemme know man
so, I could have said like Richard is fat and smelly don't listen to him.
and it's not that I'm anti SAFC, it' s just that I know the fmu/fp/o2 clamp combo works, and works well.
I dunno much about the safc, so if it can lean out the top-end, then great. but as is, he still needs fuel pressure holmes.
and it's not that I'm anti SAFC, it' s just that I know the fmu/fp/o2 clamp combo works, and works well.
I dunno much about the safc, so if it can lean out the top-end, then great. but as is, he still needs fuel pressure holmes.
He bought the ebay stuff to stabilize his idle fuel pressure wich is all well and good if he can get it to work as advertised i never could. But i think he either forgot or got confused on his way to a rrfpr. Don't get a sandy gina on my now. You would smell a month away from your yearly bath as well. The creek is finally gettting warm enough for that stuff in KY gees. :gay:
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07-23-2007, 02:52 PM
#39
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im laughing over here. i threw in my two cents and you're freakin out on me, I barely read through the posts.
and please refer to it as a fmu, i hate seeing acronym rrfpr
and you better watch who you mess with, I can remove your avatar, then you'll feel silly paying $3.50 for nothing :gay:
and please refer to it as a fmu, i hate seeing acronym rrfpr
and you better watch who you mess with, I can remove your avatar, then you'll feel silly paying $3.50 for nothing :gay:
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07-23-2007, 02:55 PM
#40
nah i am just extremely bored. Car is running well and i have nothing to complain about. Making myself think you have it in for me makes the posting more fun. Still 90 miata deserves the full attention of the posters, after his oil burning troubles etc, i realy hope he gets his stuff together soon 
he seems to get abit confused sometimes but i believe he has the right idea now hopefully he just needs to figure out how he is to go about it.
he seems to get abit confused sometimes but i believe he has the right idea now hopefully he just needs to figure out how he is to go about it.
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