i was reading online today about AFC's and they sound really interesting. being able to plot a/f ratios, rpm shift points... ect... but i was curious if there is any potential for getting any gains out of a n/a car... i would think it could help a juiced car... and def. a boosted car... but i have no idea about a na car. anyone know? thanks in advance.

-jon

 

I was wondering the same thing. My brother just ordered an APEXi SAFC for his 92 Mitsubishi Eclipse Turbo 5spd. He explained to me all about it and I was wondering if it would help my 95 Maxima?
-Nick

 

For me, I had to lean the fuel out N/A and it showed decent gains, but I have the walbro fuel pump so It probably just corrected it to where the a/f ratio should be with the stock pump.

 

If your running N/A spending $300 for an AFC doesn't justify the gains. You'll probably see like ~1hp if your not boosted..

 

I concur. There are some gains to be had NA since the ECU dumps quite a bit of fuel at WOT, but nowhere near the amount for FI cars. The OEMs want you rich on the top end just to make sure nothing bad happens to the engine.

Like Iron Lung I am very rich at WOT since I have a Walbro fuel pump. AFCs are cool, but for a NA Maxima I doubt the $/hp is very high.
-hype

 

My friend got an AFC for his 01 GT (n/a) and gained I believe ABOUT 6hp and 10tq or something close to that. I would think 5th gen n/a's would see about the same gains, I don'tknow about 4th gens though.
I would say if you're all done w/ your car except for S/C ro turbo, than go for it, otherwise, it's better to spend that 300 elsewhere.

 

I'll find out what kind of gains there are with an NA 2k auto pretty soon.

 

Hmm if you buy the Walbro pumps, I think you would be better served by buying a upgraded fuel pressure regulator instead. That way you can adjust your idle and wot fuel pressures w/o the expensive safc route.

 

We'll find out soon. I have the Apexi Rev-speed meter with G-sensor, so I can get a decent feel for my power. I was going to install the S-AFC II once it is released in the US officially (warranty concerns). My tuner friend says they get pretty good gains on NA cars even if they aren't running rich. I'm hoping for a average of 5 HP's. I thought the other monitoring features would be cool to have too.

 

yeah, the monitoring features are what i am most interested in. and thanks for all of the responses.

 

Well off of my old dyno I was able to see that I was running abnormally rich. I got the SAFC-II and since then I felt it pulls harder, to prove that I wasn't wrong I had a friend who drives a 3.5 auto max race twice, the first one with my file 2 which was stock and I lossed to him. The second race I put it on file 1 (which me and my buddy tuned to our best ability looking off my dyno & A/F chart) the results was I pulled hard away from him. We have raced numerous times and he can agree with me that with the SAFC , it did provide excellent gains (at least for my car), I can't say this would happen to every car but I think with it tuned correctly it will show some gains.
I wanted to dyno tune my car to see the difference but haven't had the time nor money to do it so maybe later this year...

 

even if it only adds 5hp, some people spend well over $300 for a catback, which I doubt gives you much more than an AFC

 

Why would 5th gens see more gains than 4th? Is it the poor flow at high rpms without a mevi?

 

 

Even if you don't gain too much power, an AFC has the potential to gain across the entire power band rather than just the low end or high end. There's really no cons to the AFC except the fact that you need to dyno to get the settings right.
-hype

 

Why do you have to dyno? if your a/f is not at peak, then any adjustment to get you there is worth it ... right? I mean a dyno would show/prove the end result.
And why are people using a Walbro pump? stock replacement for later boosting or cheaper than OEM?

 

There is a certain point at which leaning out the car is harder on the engine (higher EGTs, etc.). The stoichoimetric ratio is 14.7:1, so on an NA engine you want to be around ~14 A/F. Any leaner and you raise the EGTs and have a higher potential to detonate. That's why you really need to dyno.

Nitrous
-hype

 

Dyno also can show A/F ratio, so you can see the A/F ratio at a specific rpm so one can tune it richer or leaner for that rpm, it more accurate to dyno it your SAFC rather then just guessing.

 

BTW, where is the cheapest place to get one? My brother's boosted and in the market for one.

 

I got a SAFC-II at www.edoperformance.com
for $330

 

Ok, I have to interject here. First off for all the NAY-sayers, lets look at the MEVI with little or no peak power gains. We lose mid range power, but the overall gains on a dyno map shows excellent gains on in certain ranges. I assume that I'll see the same kinds of gains once my AFC-2 is installed. I really dont expect my peak power to rise much, but I do expect to see my power to increase in the rpms that the a/f mixture is off.

 

like the previous thread i posted about passin the smog with afc, i guess tat's jus one thing to try out on either N/A or boasted spec...

 

They sell it on ebay for $5 cheaper. I just received mines from them. Took about one week.

 

hey lonely driver- Do you have a converted instruction manual for the wiring of the SAFC-2?

 

I don't have the english manuals, but I think I saw a pic or diagram posted that showed where each wire is suppose to go.

 

thanks, jime sent me the pic