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SAFC II help

2K views 22 replies 7 participants last post by  IMPRIMIS 
#1 ·
hey guys. i've been lookin in the search fourm for any info bout the SAFC II...and, i can't find what i'm lookin for. anyway, might be a really dumb question, but:

A.) what is the difference between a Standalone system, and the SAFC II?

B.) what exactly is the SAFC II, and what does it do...also, same for the standalone system.

might sound like dumb questions, but, i kinda would like to know.
 
#2 ·
I have no idea what Standalone is, however, here is S-AFC I found written by Das:
dasgalloway said:
...Can allow you to maintain that conservative tune for 99% of driving, but give you a little more oomph when you want to mash out the pedal on the right...By adding the SAFC, you gain the power to change the amount of fuel the ECU is spraying into the motor by tricking it into thinking it's got less air entering the intake than there actually is. This will cause the ECU to spray less fuel, resulting in a "leaner" mix. LEaner mixes make more power than richer ones (they burn hotter and more completely)... the downside is that if you run it too lean you'll start melting things and causing all sorts of other problems. Ask around for a local shop that might be able to help you out... and expect to part with another $100-150 for the tuning time.
 
#3 ·
I dont know much about standalones but I can answer ur 2nd question lol. An safc is a product made by Apexi and it suppose to adjust your air fuel ratio. It can let you adjust your car to be more lean or rich depending on the areas you need it under WOT. In other words, it pretty much tricks the ecu and sends different signals.
 
#5 ·
thksdad said:
so, how much do these run? is a standalone like a whole new wireing harness for your car...something to actually "tune" and adjust your car...ie higher RPM's, faster speeds...etc?

SAFC About 300 dollars

ALso, a standalone will do the same as a SAFC plus a lot more

Just depends on the one you go with


The second-generation S-AFC II is a fuel computer that adjusts fuel/air ratio by modifying the air-flow meter/MAP sensor signal. The S-AFC features a user-definable, eight-point, adjustable fuel curve that can be set in 500 RPM increments. The range of fuel adjustment is +/- 50% at each of the user-defined setting points. On hot-wire vehicles, the Deceleration Air Flow Correction function is capable of curing the erratic idle and stall problems associated with open-atmosphere blow-off valves on hot-wire air-flow meter systems. The S-AFC is capable of monitoring and replaying the following data channels in Numerical, Analog Meter and Graph displays: Intake Manifold Vacuum/Boost Pressure, Air Flow Capacity, Intake Manifold Pressure, Karmann Frequency, Engine RPM, Throttle Position, and Air Flow Correction %. Due to the complexity of this product, A'PEX recommends having the S-AFC and other A'PEX electronics installed and tuned by authorized A'PEX Power Excel Shops.
 
#6 ·
A stand alone basically does all that an SAFC can do as well as adjust timing and a number of factors. This takes longer to tune costs more but it controls what the ecu would normally do on its own. Part throttle air fuel and everything in between. thats the very small answer version. THere is more but that is a basic Idea. It in essence is replacing your ecu when it comes to fuel managment and performance applications as well as daily driving applications.
 
#7 ·
A piggyback ECU (the SAFC, Emanage, etc) simply changes the signals going into the stock ECU... "tricking" it into changing the way it controls the car.

A standalone ECU completely replaces the stock ECU... and you have full control of the motor without any trickery.
 
#9 ·
blondebond said:
Thanks Das I knew you could explain it better than me. :)
Eh I said the same thing, I just used less words. ;)

A standalone is going to START $2500 installed... probably more. Not only do you have to make new wiring harnesses and pay for the ECU itself, but you have to pay someone for a LOT of drive tuning time.

Anyone who says they will do it for less does NOT understand how much work it will be, and your bill WILL BE more than their first estimate.

For a daily driver NA car? Probably not worth it.
 
#10 ·
okay...so, i think i've got a general idea now...so, here are some more questions.

A.) i'm planning on getting the SRT intake with new R-ECU. will the Apexi SAFC II work better with the SRT intake?

B.) which Apexi SAFC is better to get...i've seen a few different ones out there...the second generation, the original one i believe...insted of the silver nob, there are 4 arrows....and, a couple of others.

C.) how much more power will this probably give me after tuning?
 
#12 ·
-so, if i get my SRT intake, its not going to help if i get the SAFC? now, if i keep my AEM intake with stock r-ecu will it make a difference?

-the best ones for your money are the Ver I and II...?

-and, lastly, if my car only has Greddy EVO II exhaust, AEM intake, how much more will it give me?
 
#13 ·
thksdad said:
-so, if i get my SRT intake, its not going to help if i get the SAFC? now, if i keep my AEM intake with stock r-ecu will it make a difference?

-the best ones for your money are the Ver I and II...?

-and, lastly, if my car only has Greddy EVO II exhaust, AEM intake, how much more will it give me?
SRT RECU works only with the SRT (3.5" piping compared to the norm. 3)

VER I and VER II have slight dif, go with II

3> Each car tunes out dif have to do it
 
#14 ·
Install everything at once and see what happens. If you do not like AEM intake, go with SRT. Just try as best setup as you want and if you do not favor the setup, go with different mods. I have seen a few complains about AEM intake, however. I'm waiting for header and camgear to tuneout at once with SAFC
 
#15 ·
thksdad said:
-so, if i get my SRT intake, its not going to help if i get the SAFC? now, if i keep my AEM intake with stock r-ecu will it make a difference?

-the best ones for your money are the Ver I and II...?

-and, lastly, if my car only has Greddy EVO II exhaust, AEM intake, how much more will it give me?

Until you do headers there's really no reason to tune the car, even with intake/exhaust.

There's no need to piggyback the r/ECU with an SAFC... you won't get any more power.

An SRT intake can be run with the r/ECU alone... but cannot be run with only an SAFC (No r/ECU). The car will not even idle.
 
#16 ·
If you like your aem intake then keep it and get an SAFC II and forget about the SRT. IF you don't like it and don't want to go to a shop and get tuned and what not then just get the SRT and call it a day. The SRT chip tunes the car faily well. When I had mine I was tuned to about 13.7:1 with SRT, header/Y pipe GReddy exhaust and HKS cam gear.
 
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