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s-afc 4age ITB's

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hey people ...

i have a ke70 with 4age fitted along with tranny and diff .

this 4age is a MAP sensor one  

i have 20v throttle bodies a vaccum manifold and an APEXi S-AFC 

10 years ago i have fitted  these  itb's and tried to run them with stand alone megasquirt but the project failed due to money shortage

while on stock ecu , couple of days before megasquirt, car idled smooth run good . the problem was that it was too rich .

i had an AFR of 12.0 

mid range revs was about 13.0 and high revs about 13.5 

all vaccum hoses 100% sealed , no air leaks 

ITB's 100% syncronized .

my latest acquisition is that s-afc i got on ebay for 200$ used .


anyone knows if :

the safc can reduce the proper amount of fuel on idle so my afr gets around 15.0 ?

the safc can add  the proper amount on high revs so afr will be around 13.0?


any advice will be appreciated.


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forgot to mention ...

i know that 20tps much be connected to 16v harness in reverse order 

because 16v tps works clockwise and 20v tps anti-clockwise 

the difference is that in what  1+3 pins  of 16v gives 5.8kohms and 20v gives 3.7kohms 

don't know if thats gonna be an issue...

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SAFC and stock ecu is pretty shit as you'll be chasing your tail as you don't really know what the oem ecu is doing...what happened to the megasquirt?

I've got megasquirt on my e30 its a way better option than safc. 

Edited by ke70dave
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"i had an AFR of 12.0, mid range revs was about 13.0 and high revs about 13.5 "

What were you using to read that? Lamba gauge fitted? 

This guy reckons that driving around casually in closed loop mode DOESN'T use the AFC, but at wide open throttle it just ignores the oxy sensor and reads the AFC chart.

"Basically what the S-AFC does is alter the voltage the ECU receives from the MAP sensor. This causes the air/fuel mixture to either go leaner (-) or richer (+). You can adjust in increments of 2%. You can fine-tune the mixture at different RPM points (800rpm, 2400rpm, 4000rpm, 5600rpm, 7200rpm).

The ECU won't use the values of the AFC while in closed loop mode (under 80% throttle). But when you step on it (when racing), the ECU goes into open loop mode, ignoring the O2 sensor and only relying on the MAP sensor for data. So the Gen1 AFC is only usable under what (Wide open throttle) situations. "



Which means no, it won't help your AFR anywhere in the rev range unless you have the throttle wide open, not what I expected at all.


However, you might get a wide-band controller-  Wideband controllers with simulated narrowband outputs are on the web, they read a wideband sensor and send an adjusted narrowband voltage to the ECU .



I wonder why ITBs make it rich, I thought they would flow a lot more air and lean it out.

Edited by altezzaclub
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