Ok heres the deal...I bought the car, a 91 TII with the SAFC already installed. It currently is running 550 primaries and 720 secondaries. Well the guy before me had it tuned oddly...or so I think. I am at +12 at idle and it gradually leans out to -7. I cant understand it. I want to lean it out some but want to be carefull. Wouldnt it make since to have 0 correction until 3800, and then lean out the 720's? I can see keeping the primaries a little richer, as I am running 10 pounds but I am hitting -7 before 3800. Any suggestions? Thanks in advance.

 

Is this the SAFC with a row of *****, or the S-AFC(1) with the electronic display?
You're right about the +12 idle being high.
Even my 110,000 mile, worn out, low compression, cracked apex seal, daily driver turbo motor idles at -8.

An air/fuel ratio gauge is a big help.
A wideband is best, but even a cheap narrow band gauge is helpful.

From your description, I see you understand the problem.
The PO may have the timing way retarded.
Yes, I'd dial up the primaries maybe +10 or +20 at 3K & 4K where the boost rolls in.
Maybe set 2K at -5 or -10 for open loop crusing.

 

Well I finally got the courage to get in there and see what was up. It was worse than I thought . He had correction set at +21 at 5600...I was floored. I basically zeroed it out all the way accross the board. I am still pegged full rich, as I am assuming the 720's are still dumping way more than enough fuel. The difference in the car is increadible. It pulled ok before, but it now drives like a tottaly different vehicle. MPG has obviously increased, and acceleration all the way through the powerband is tottaly different. Of course I basically now have an SAFCII sitting in my car for nothing but to look pretty, but when I get a chance I guess I will take it to the dyno cause Im sure I can still milk a few HP out through leaning out those 720's but I dont want to risk anything withouth a wideband and a dyno.

Is there anything I should be aware sence I zeroed out the correction? Thanks again.

 

I'd lean the LOW map.
Something like:
1000 -5
2000 -15
3000 -15
4000 -20
5000 -15
6000 -15

 

would this setting be the same, or anywhere close to the same for a 89' vert, with SAFC, header, and full exhaust??/ im set at 0 across the board (i have the SAFC that have the 5 knows on the front of it) ....when ever im at the higher rpms shifting i get fire, i only assume that im running rich up high too, and at low rpms the exhaust smells REALLY rich, but i dont have a a/f wideband, or regular..

Thank You for all your help

Caleb

 

An NA should need no extra fuel on the high map.
Of course you can save fuel by leaning the low map.