FI-SDOL- IAT and ECT ve mulitipliers
08-22-2007, 05:31 PM
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FI-SDOL- IAT and ECT ve mulitipliers i have a COS with 2 bar from efilive....
when using the IAT and ECT mulitipliers for desired AFR throughout all IAT's and ECT's what is the basic example?
(ie) higher IAT's mean less fuel is needed
(ie) higher ECT's means more fuel is needed
and vice versa
i hope that made sense but can some one help me out on that.
Thanks,
Tyler
when using the IAT and ECT mulitipliers for desired AFR throughout all IAT's and ECT's what is the basic example?
(ie) higher IAT's mean less fuel is needed
(ie) higher ECT's means more fuel is needed
and vice versa
i hope that made sense but can some one help me out on that.
Thanks,
Tyler
08-23-2007, 12:50 AM
#3
airmass=VE*cylinder volume*MAP/(R*TEMP)
TEMP is blend of IAT and ECT. when either one of them goes up, TEMP goes up, and thus airmass goes down. if the blending between IAT and ECT was set up perfect, the multipliers should be theoretically not needed. but than again, i heard some well sourced rumors that even with the blending perfect it's not enough, that's why the multipliers are there.
the real problem is to figure out if the change in airmass comes from change in VE or TEMP estimation. one equation with two unknown has an infinite number of solutions after all...
TEMP is blend of IAT and ECT. when either one of them goes up, TEMP goes up, and thus airmass goes down. if the blending between IAT and ECT was set up perfect, the multipliers should be theoretically not needed. but than again, i heard some well sourced rumors that even with the blending perfect it's not enough, that's why the multipliers are there.
the real problem is to figure out if the change in airmass comes from change in VE or TEMP estimation. one equation with two unknown has an infinite number of solutions after all...
08-23-2007, 07:12 AM
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i do understand the fact that when every air is heated (higher IAT) it is not as effecient as when it is at cooler temperatures... and i also understand that when a motor is heated above 190 it starts to take a dip in performance also meaning its not as effecient either....
im wondering if some one can manipulate these IAT & ECT tables enough to make a SD OL car drive/start/cold idle like a MAF car.
im wondering if some one can manipulate these IAT & ECT tables enough to make a SD OL car drive/start/cold idle like a MAF car.
08-24-2007, 07:35 AM
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what about whenever the car is on a cold start with low ECT and low IAT's the first 3min that my car runs it needs alittle help since i have no IAC valve (i welded up my TB and set it like a carb) it idles at about 600rpms for a little while.... would more fuel or less fuel be desireable on these cold starts... im not worried about getting the rpms higher for the first 3min or so because i understand that I would have to have a IAC valve to open for me... i just want a crisper idle
08-24-2007, 10:19 AM
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I've thought about adding a couple of drill bores and a
taper bleed screw as an alternative to TB blade drilling,
to make an adjustable baseline air path. Not that I need
it but I can see how to do it on a stock TB casting. Not
a big fan of computer controlled idle myself, it tends to
"think too much" and overreact.
If I could find a 85mm side-draft carburetor that fit up
to a Professional Products intake you bet your *** I'd
give it a try. Rig the IAC to only comp the air based on
the air conditioning clutch voltage and you be done.
taper bleed screw as an alternative to TB blade drilling,
to make an adjustable baseline air path. Not that I need
it but I can see how to do it on a stock TB casting. Not
a big fan of computer controlled idle myself, it tends to
"think too much" and overreact.
If I could find a 85mm side-draft carburetor that fit up
to a Professional Products intake you bet your *** I'd
give it a try. Rig the IAC to only comp the air based on
the air conditioning clutch voltage and you be done.
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08-24-2007, 02:16 PM
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Originally Posted by Frost
why would you weld up your IAC and "set it up like a carb"? What does that even mean?
08-25-2007, 11:33 AM
#14
Originally Posted by ty_ty13
believe it or not after the motor has just little bit of heat in it 130*F+ the car idles the best it ever has even after throttle blips decels or anything like that...
With base airflow setup properly, throttle blade stop poition set, commanded AFR met, sometimes IAC counts vs. effective area tweaked, and throttle cracker and follower set, I have gotten around 80 of these boogers to act just like they should and never had to mess with IAC outside of software. But if what you are doing works for you...
08-26-2007, 09:17 AM
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im not gonna say its the bestest acting stealth street car or anything.... but as soon as the motor gets around 140-150 degrees it acts fine.... and im fine with that because its not a daily driver.... but even when the car was a daily driver i'd always wait for the ECT to get up to the same temperature any ways.... so oh well...lol
08-26-2007, 10:34 AM
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Originally Posted by RedHardSupra
really? cuz i could've sworn that changing RAF influences my idle and i've been in SD since '05 
OLFA is the Open Loop Fuel Adder, it's kinda like PE, but usually used during cold starts, that's why it's ETC referenced.
OLFA is the Open Loop Fuel Adder, it's kinda like PE, but usually used during cold starts, that's why it's ETC referenced.
The only thing he can do to improve the drive-ability and startup performance now that the IAC hole has been filled in is to try and swap in a C5 drive-by-wire setup. Then, the TP% of the blade is controled by an electric motor and he can have the idle control functionality back.
