I've had my Mufflex 3" catted Y on for 4 yrs or so. Within the past year
the fuel smell kept getting stronger and one cat seemed to rattle at WOT
(at first I thought it was detonation by my tune was spot on).

Anyway I bought 3" Magnaflow spun cats and had them installed. Well
what do you know, one cat was completely gutted (nothing inside) and
the other was half clogged. I asked my engine guy, "where the hell is the inside to the cat" ?
..he replied, "probably somewhere on the highway where you left it"!

*This is just your friendly reminder that if you think your cats are shot, get
them replaced!*

 

Nice.. did they smell like rotten eggs?

 

I did have that rotten egg smell a yr ago but I guess
it went away when I blew out the cat

 

Did ses light come on? Should have when cat went out the tailpipe. Or were the cats deleted?

 

The SES light would occasionally come on for
the O2 sensor but only when I beat on it.

I'm just wondering if the backpressure diff from each side would mess anything else up. Either way I'm bringing car back to TTP to check the tune.