EFIDynoTuning Forum

How is catalyst protection invoked? I noticed when I’m in boost at times the ECU/PCM was demanding .7 Lambse when logging data. This was odd considering my base fuel table (FN1362LX) does not contain a value of .7 Lambse. So I did a little digging and found the catalyst protection Lambse values in the tune and they are .7 Lambse. My wide band readings are very close to Lambse so I’m operating under the assumption that my fueling is appropriate. Is this a red flag? Perhaps the catalyst temperature calculation needs correction now that the car has a supercharger and making more power? Any insights and/or recommendations are appreciated. Thanks

nope thats how it functions stock. My marauder goes in to cat protect everytime I get on the interstate at least once. If I didnt have a way to log or a wideband you would never know it as most people are completely unaware.

You can raise the commanded lambda if you want or disable it if you dont have cats otherwise leave it be as it helps the cats survive your driving habits.

I raised the values to lambda of 1 for tuning purposes but now that a have inefficient aftermarket high flow tiny cats I might just revert those values. Do you agree?

yep

Thanks