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Hi guys!

I am a proud owner of Audi 100 C3 with 2.2 MC2 turbo, with unchipped 165HP.
I plan a little upgrade, so I have bought the AEM wideband o2 sensor, a chip and 1BAR westage spring from unknown company "KL-Racing".

While increasing the boost from current 0,4 bar to 1 bar, I really want to make the fuel mix right.
Previous owners have messed with my CIS system, so now my goal is to make sure the car is not leaning out on high revs.

So, coming to the point, do anyone happens to know which is the best safe AFR at WOT, on cruise (50% throttle) and on idle for our 5-cylinder 10V turbo engines?

I assume, that WOT AFR should be about 12:1, but I heard from fellow C3 owner, that he tuned his car to be at 13-13,5 AFR on WOT.
Regarding partial loads I have no clue.

Idle should be 14.7:1, correct?
 

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13:1 at WOT in a two valve turbo car! Holy crap! That works for modern combustion chambers and direct injection but not on these old crappy chamber heads with no mixture tumble.

I wouldn't want to be any leaner than 11:1 under high boost. As you run leaner, which raises EGT, you have to pull timing to prevent detonation, which also raises EGT, and the high EGT makes your exhaust valves really hot, which invites preignition, as well as kills valves and guides.
Idle and cruise, stoich is fine.
 
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