ka-t tuning with safc

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ka-t tuning with safc

Postby poshatch » Sat Apr 09, 2011 4:24 pm

91 ka24de-t, t3t4, tiny fmic, 2.5" turbo back, 38mm external wg, dump tube, 370cc inj, n60 maf, safc2, aem wideband, 255 lph fuel pump, autolite plugs, stock everything else, 7psi

so im looking to get some decent power but nothing too much out of this set up

but id like input from those running an safc2

so basically i have the safc2 to read 2in 5 out from the n60 maf to compensate, and i have a super rich tune atm with no NE points set, throttle points are 10% 50%

when you tune with the safc2 to compensate for the maf and for the inj change, does it read the maf voltage, then compensate for it with the maf settings, then compensate again by you taking out or adding in fuel, and outputing a maf voltage that the ecu is going to red and produce the correct duty cycle for those inj that you want for that rpm point?

the only place i see the ecu being fed information is the maf sensor so i have to assume this is how it works??...what does this do to the STFT and the LTFT? the ecu is being fed information that it uses and outputs what you desire but not what the engine is actually getting, if you tune the safc2 to run for lets say a flat rich afr then dosnt the o2 sensor read a rich condition, richer than it would like on the closed loop and therefore want to adjust the STFT to a leaner condition?

this would affect the overall tune that you are trying to get wouldnt it?

im trying to get some good information about the safc2 and tuning it so i can tune it to be as precise and reliable as possible, all input is helfpul!

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Re: ka-t tuning with safc

Postby infinitedrift » Wed Apr 13, 2011 7:08 am

is the car running at all, drivable? I have the same setup only I have a tuned ecu, my safc is not controlling anything since the tuned ecu was installed. I have been searching and im finding 4in 5out setting but im going to try yours. When I disconnect the maf plug on the safc the car runs great when I plug it back in its horrible.

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Re: ka-t tuning with safc

Postby chillmieste » Fri May 06, 2011 2:05 pm

before i went megasquirt, i had pretty much the same setup as you. except I had ran 740cc injectors. You are correct the safc uses the maf voltage to "trick" the stock ecu to make it able to run larger injectors. I ran a 2in 5 out setup for 8 months no problems. I also loved the decel feature cause i was running atmo blow off valve and it never stalled once setup correctly! I see where your going with the sft and lft but when the 02 tries to adjust for a leaner condition the afc ignores it and still puts out YOUR INPUTS. I could be wrong but my afrs on a cold motor doesnt change when its hot. And I also never had a problem with the setup so i wouldnt worry about the 02 sensor messing up your tune. at idle it jumps from 14.8-15.3. Although you can use the safc to make the car run with turbo, IT should NOT be the only source of tune. Its nice to have the afc for a fine tune, or a temporary setup. Dont expect big power with just a safc tune alone. Also i would retard your ignition timing a bit, since the afc uses maf voltage ur computer likes to advance the timing and that can equal detonation. Since i ran 740cc I had my timing retarded to 8 degrees to avoid all possible detonation. I could have made more power but it was only a temporary since i finally got what wanted out of my megasquirt later down the road. For your setup i think u would be fine in the 15-18 degrees of timing. if you have anymore question jus let me know i fooled around with the afc a lot when i still had it. hope this helps

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Re: ka-t tuning with safc

Postby poshatch » Mon Jun 06, 2011 7:30 pm

thanks for the reply ive been working on so much other stuff i havnt had a time to really check this

i went ahead and got an emance reflash for what i have on the car as the base tune then im going to fine tune it with the safc 2 as much as possible ive read that it is pretty effective to do that combo of tuning.

i JUST JUST got the ecu back and im trying to get the safc 2 to not correct ANYTHNG and just run straight ecu since i need to know what im working with so actually i have some more questions if anybody can chime in...

the maf correction should not be needed now with the reflash since its corrected for so with the base setting of the hotwire it should be 01 in 01 out or 05 in 05 or some combination of the same numbers correct???

im also running a atm bov im still fiddling with the decel points

good to know the ecu ignores the pesky o2 correction but i plan on running the car mostly in WOT so im not too too concerned about LTFT

i have the base timing retarded a decent amount since im still trouble shooting i always want to be in the safe, however, i think the reflash re-maped the ignition to not advance as much so does that mean i can put it back to stock 20* btdc?

any help is appreciated thanks!

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Re: ka-t tuning with safc

Postby WDRacing » Wed Jun 08, 2011 7:23 am

5 in 5 out for the stock MAF or if the ECU is programmed for the MAF you're using. If the ECU is programmed to retard timing on boost then you can put the timing at 20*.

Also, the SAFCII has a datalog mode that makes it easier to fine tune things, like peak RPM reached etc.

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Re: ka-t tuning with safc

Postby koukiman » Sat Feb 04, 2012 12:31 am

im kinda having same issues....

Bought the car with a sfac already hooked up.
Jus rebuilt the entire motor and now turbo, got my emance ecu plug right up started right up but now i think the safc is fucking it up. Does the emance still read the sfac or can i jus unplug it from the harness? like i said car starts up no problem but when i give it gas to go it jus bogs and stalls this is why i think the sfac is fucking it up... And im not sure how the hell to work this thing, i tried playing with it but with to no success.

Help me out guys!


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