would running 10 AFR for 80 miles stuff up a cat?
 

i'm battling an issue where my car is making 30hp less than expected on 10psi. The cat in there is only 2 months old but i had a period of about 80 miles running at 9-10 afr because of a tune issue and before i had a wideband installed. i'm trying to figure out if this was enough to damage the new cat and give me enough back pressure to lose 30hp what do you guys think? far reach?

Yeah, that will screw up a cat.

take off cat and see if it makes a difference.

(zack morris's phone)

Can screw up a block too

What Brain is trying to say but doesn't feel like typing out on Zack Morris's phone is that you should change your oil ASAP because of the massive fuel dilution it now has.

Brain, running rich can damage the engine?

Cats are for pussies.

Yes.

Yes.

Fuel acts as a solvent for oil, so bathing the cylinder walls with fuel will wash the oil film away and make them wear at an accelerated rate. In addition to this, once the oil have been washed away the fuel can get passed the rings and into the oil, if it gets diluted enough you could spin a bearing.