im kidna a newbie to it, so what does it actually do ? and how do you set it up properly ?

im thinking of getting one for my 86 NA

 

it really doesnst serve a purpose unless your really modding your car.

 

you can add or subtract fuel in certain rpm increments in order to get more power... you will see a power gain by leaning out your car in higher rpms..

 

leaning out the fuel wha?... i thought what could damage your motor.

 

leaning out meaning subtracting how much fuel per air.. like your a/f ratio

 

leaning out for a period of time can make your engine go BOOM!!! I am using an SAFC to help add more fuel for when i add more boost... i dont really know what to use it for on an NA other than with lots of mods that require more fuel

 

You use the SAFC to lean out the AF mixture to a safe level and gain more power from running leaner NOT LEAN. The stock maps run pretty rich so there is power to be gotten by tuning.

 

on an n/a, which runs rich on top end, the safc is used to lean out the fuel mixture to make more power, unlike a turbo engine where this can be fatal. rarestrx7 on this forum has some dyno info in the 2nd gen dyno section about how he increased 20+ hp by leaning out the fuel on top end.

 

Even if you're not modding your car the AFC (fuel tuning in general) can add more power than you have stock. It's just more "dramatic" when you add other parts to the equation. The top end on the FC (well...pretty much all rotary cars from the factory) is pig rich so leaning it out a bit will help power.

With that said it's not something you just go about blindly (especially if you have a turbo car ), so if you don't know what you're doing or don't know someone else who knows what they're doing then leave well enough alone or you could end up much worse than before.

Kiyo

 

I used to have one on my old N/A leaned the car waaaaay out and it went a high 15.9 with a BONEZ street pipe, home depot intake and pulled like a bat out of hell.. although, i tuned the car at the track instead of using a dyno..
Dave

 

No offense, but either that car was leaned WAY too far out and you LOST power, or that car was already dead man . Or you could've just did a type cuz a 15.9 is only .1-.3 faster than a "normal" stock FC man .

 

the best i could get mine to go when i first got when it was all stock was a 16.7 and all the other ones i seen out there that night were in teh 17's
Dave

 

theres a **** in the engine bay on the passenger side that could adjust the leanness of the fuel or the richness

should it be set leaner ? or richer? and getting a SAFC would kinda serve as the same purpose as that **** thing right ?

 

thats just idle mixture, the s-afc controls rpms up to redline

 

Stock brand new s4 n/a runs a 8.5 0-60 and 16.5 1/4 mile... add to that the fact its 15+ years old and a stock fc would not run 16.0 to 16.2, plus the numbers that magazines and such get is usually better than the average (and sometimes good) driver will get

 

so would itbe good/bad torun it all the way lean or all the way rich on idle ?

so a s-afc WOULD increase power thruout all the rpms wouldnt it ???

right now im running more towards the lean part wut if i made it run all the waylean ? or all the way rich ?

 

for the idle mixture just set it to a place where your car seems to cooperate the most.. like if you turn it all the way lean or all the way rich your car will start to sound like it wants to die (usually)

as for the s-afc, it is mainly used in the higher rpms cuz thats where it shows the most improvement, its impossible to say what you should do (lean it or richin it) the best bet is to get on a dyno and dyno tune the s-afc, you CAN use an a/f ratio to do it, but thats harder and less accurate