AFR with overlap

[0rion]

Any decent way to tell what your AFR at idle is with a good deal of overlap? I realize the overlap skews the wideband but it sucks not knowing exacly what the AFR during open loop idle is. I guess you just get the car to where it's idling correctly and call it good?

[12secSS]

Your question is much like answering the following question: "if you have a mixture of water and milk, is there any way to tell how much is water and how much is milk?" Simple answer, no. But you answered your question, just get the idle to be stable by using the spark table, airflow tables and even biasing the AFR to the most vacuum (lowest MAP).

[0rion]

Your question is much like answering the following question: "if you have a mixture of water and milk, is there any way to tell how much is water and how much is milk?"

Actually, you would use a centrifuge to seperate it. Thanks for the reply. This was one of those questions I kinda already knew the answer to but wanted to see if I was missing something.

[edcmat-l1]

Any decent way to tell what your AFR at idle is with a good deal of overlap? I realize the overlap skews the wideband but it sucks not knowing exacly what the AFR during open loop idle is. I guess you just get the car to where it's idling correctly and call it good?

Not with your wideband. We use a gas analyzer. But, like posted above, set to smoothest idle, highest vacuum. Then start taking fuel back out of it til it starts to roughen up again. This should get you to the leanest point, without effecting the idle quality too much.