So CEL threw P0420 code. I changed the o2 sensor and still have p0420 so I'm going to change my cat next. Thinking about getting a high flow(magnaflow), standard/oem are they all high flow? I'm also not sure if I need a direct fit or universal?(pic below)

 

I'd say universal. Looks like somebody has already changed it...

 

Thanks that's what I thought. When I was down there changing o2's I tried to look for a brand but nothing, it might just be a muffler shop cat... -_- So as for standard(99234HM) or oem(51234) grade would it matter?

 

OEM will last longer, bust costs a lot more. Plus, you will likely have to chop it or reweld flanges on to your flex and mid pipes since they were chopped off for your current cat...

 

He's talking about the Magnaflow "OEM" grade cat, not the actual Honda cat (which, yes, is absurdly expensive). It looks like they both come with the o2 bung already on, which is good. I would go with the "OEM" grade version; they appear to be very similar in price. In fact, I wouldn't be surprised if they were basically (or exactly) the same thing.

 

Yeah I got the universal standard. They might exactly the same.

 

BTW: when you replaced the 02 sensor, did you just get a new oem one. I have
heard of some ludes having probs with the bosch O2s.

 

I got denso o2's

 

Sweet man.