Just got myself an AEM wideband and have picked up a 5-**** "older than time itself" SAFC and plan to do a a bit of very basic and mild fuel tuning on my 1991 S5 Tii FC. Don't have any major engine mods; in fact I've just got the emissions stuff removed, full intake & exhaust, stock & freshly cleaned injectors and a full tune-up. Have also done a complete rewire of the fuel pump to a straight relay and removed the variable resistor so I know it's going to be running rich.
The 5-**** SAFC just has 5 rpm levels at which to adjust the fuelling (800, 2400, 4000, 5600 and 7200rpm), and can adjust up to 30% either way of stock. Am probably going to do my tuning for 4000, 5600 and 7200 at WOT and will probably take a reading for 2400 at WOT and also when cruising too. Was wondering what I should be aiming for in terms of a little leaner but still safe AFRs. Am not going to be boosting much above 10psi (12psi would be an absolute and unlikely maximum).
Idle & WOT AFR thoughts would be appreciated