Hi, so I have a 2009 Honda accord Sedan 4cyl and I wanted to get a crackle/burble tune done to it. I've got a K&N CAI, a highflow straight resonator and a muffler delete. I still have the stock cats on because I live in california and I heard that the tune could damage them and/or cause premature excessive wear? is this true if the tune is not too agressive? Here is a pic (it's still an ongoing project many more mods are to come)
If you are setting ignition timing late or opening exhaust valves early unburnt fuel will get in the exhaust and ignite in the cat. Thats how you clog up a cat real quick. I wouldn't bother tbh, as it doesn't do anything but produce noise. If you really wanted to you could theoretically hook up a fuel injector and spark plug in the exhaust behind the cat, but that is a lot of work for zero payoff.
I personally wouldn't mess with it unless you want to run into trouble come smog time. If you're willing to pay ~$200 on a regular basis to have the burbles, then be my guest. I'm guessing you wouldn't want to do that. If you want to stay within the law without major modifications, I wouldn't recommend it. Maybe, if you can switch between tunes on the fly, you could mount some sort of cutout before the (possibly relocated) catalyst and open it when you want to run the burble tune. Either way, it's going to take effort, time and money to get it to work, and it's up to you wether or not you'd want to pay that to have burbles. You'd have to run this in an "off-road" situation most likely, so that would mean mostly on the track. Sweet Accord! That thing looks great, and the fitment looks about perfect for a stanced car.