Hi all, hope you are all "negative" and well in these "quarantine" times.
Sorry if this topic was already covered, I couldn't manage to find the reliable answer.

I have 2007 Fiesta ST150 with few (engine) mods:

• Pipercross Viper VF308 CAIS
• Scorpion 2.5" downpipe, but stock cat
• Scorpion 2.5" cat-back
• lightweight flywheel

Before doing some mapping, I went to log the car and it turns out that it is running too rich (15:1 at idle, around 10.5 just before redline). Generally, car feels alright, snappier with those few parts, especially in the low range.

Since I got the car (all stock, with some unshielded K&N 57i), it was very hungry (13.0 - 14L/100km or 18 - 19MPG for you imperial guys). After some fixes (chain, lambda, etc) and upgrades, it dropped to 11-12L/100km (19 - 21MPG).

What kind of AF ratio (or AFR range) should I expect from this car?
I can provide more details, if needed.

BR,
DonYenko