Safc is working weird wondering if it could be wire of maf related

Post by **98240** » Wed Nov 01, 2006 6:54 pm

Well I am trying to tune the car right now and when I take away fuel it makes it richer and when I add fuel it makes it go lean. Correct me if I am wrong but on the aem wideband the lower the number the leaner and the higher the number is how rich it is. I dont understand why this could be doing this. Maybe one of the wires came loose from the safc to the ecu. Its to dark to work on the car right now so I thought I could get some help in solving this problem so i can work on it tommorow.

Post by **lrb_2000** » Thu Nov 02, 2006 1:12 am

no... the lower the afr number, the richer it is. lol.... are you sure you should be doing this?

Post by **WDRacing** » Thu Nov 02, 2006 6:37 am

The term is air/fuel or AF. That means air comes first in the equation. At idle its sitting at about 14/1. Thats 14 parts of air for every 1 part of fuel. Now under acceleration and boost the motor needs more fuel. So you tune it to say 11/1. Thats 11 parts air to 1 fuel. Only 11 parts air means there is more fuel then there used to be. Make it 11/1 the whole time your under boost and you'll be all set.

Best of luck.

Post by **Florida240sx** » Fri Nov 03, 2006 7:26 pm

Yup lol. Going the wrong way. I like to aim for 11.5-12, but do 11 so your safe, let the aggressive tune happen on the dyno so they can see how the car reacts

Post by **98240** » Fri Nov 03, 2006 9:01 pm

seems like my safc is working backwards then I guess. My lo throttle is about -11 all the way and my hi throttle is at about -18. and this puts me where I am suppose to be on the wideband for my afr. Or is that how the safc II is suppose to work this is confusing me. I think I am just nuking it.

Post by **Craving4Boost** » Fri Nov 03, 2006 9:57 pm

98240 wrote:seems like my safc is working backwards then I guess. My lo throttle is about -11 all the way and my hi throttle is at about -18. and this puts me where I am suppose to be on the wideband for my afr. Or is that how the safc II is suppose to work this is confusing me. I think I am just nuking it.

buddy your SAFC isn't working backwards...your head is working backwards haha...

your LO correction map settings should be subtracting more fuel than your HI maps because you need less fuel at cruising speeds. your HI map should be correcting LESS which means more of a positive number than your LO settings.....this is because you don't want to be subtracting more fuel than cruising during boost because you need more to compensate for the forced induction. (sorry if it sounds confusing)

please post your set up so we can help you more indepth.

Post by **lrb_2000** » Sat Nov 04, 2006 11:24 am

okay.. so at idle and cruising sometimes my afr will be around 16-17.. is that fine?

Post by **98240** » Sat Nov 04, 2006 12:31 pm

That is why I think my safc is working backwards since i am taking away more fuel to make it in the 11.5-12 range. I looked at everyone elses settigns and there settings for example would be at -27 lo and -18 high. my settings are opposite but on the wideband it reads the a/f is correct. which is -11 on lo throttle and -18 on high throttle. with these setting my wideband reads 14.5 on lo thhrottle and 11-12 on high.

Post by **Craving4Boost** » Sat Nov 04, 2006 1:27 pm

if any, please post your upgrades.

Post by **98240** » Sat Nov 04, 2006 6:46 pm

t3 super 60tial wastegate (10lb spring)370cc injectorssafc 2greddy type rs bovgreddy fmicwalbro fuel pumpaem widebandssac manifold (soon to be revhard)stock maf (when I get the revhard manifold I am going to put in the 300zx tt mafs)

I have been boosting 10lb for about 3 months now with the current settings on safc 2Thanks for the help