I have my wideband 4-6" from the end of my downpipe.

I have no exhaust on the DP yet, just the Turbo to DP, to fresh air.

I'm seeing A/F of 12.4 when the O2 is warmed up and the car isn't... 11.7 at idle when the car is completely warm.

Can I trust these numbers this close to the open end of the DP? I expect it to run rich as i have 550 prims on NA ecu. However, I'm wondering if it's even richer than the sensor is telling me.

Thanks,

Josh

 

should be fine.

 

that must be stupid loud

 

I get around 12.2 at idle. Are you saying with the engine off and O2 warm you get 12.4? Or just after first start you get 12.4?

 

@durtled: You'd be surprised how much the turbo muffles the sound. It was much louder when I was running it with nothing on the hot side but the manifold.

@chatchie: After I first start it and the O2 sensor gets warmed up, i get the 12.4. Once the car is warmed up (fluid running through BAC is now at temperature), I'm seeing 11.7.

I'm getting ready to hook up and try running everything on my MegaSquirt. It's a fresh build though and wanted to have it at least idling and in good running condition (pull it in and out of the shop, slow ride through the yard to free up everything that's been sitting for 2-3 years). This will also help me to understand if the numbers I am seeing are skewed in any way, by being that close to open air.

 

i think once you get over 2500ish rpms then you have nothing to worry about, it'll be moving enough air.

those AFR numbers look about right though