My next mod is going to be a header and possibly a high flow catalytic converter. Since nobody makes a bolt-on for the TSX I'm looking at a universal Carsound Magnaflow.

http://www.car-sound.com/catalog/universal/mirror.aspx (#54306 on this page seems like it would work)

Has anybody here done something like this?

 

my friend mentioned this to me the other day when i was putting on my intake, i have a comptech exhaust already. so would i see big horsepower gains from a high flow cat converter? if so how much?

 

I should be doing it, but since Acura is replacing my cat at their expense, it'll wait.

 

I don't know. I'm surprised this isn't a more common topic, as the cat is often the most restrictive element in the entire tract so it stands to reason that the gains realized through an I/H/E upgrade would be affected by a high flow cat greatly.

 

can't pass emissions here w/ that, so a no no for me

 

rmpage, you are in MA also, have you looked into if this would be emissions legal?

 

As long as the cat is properly matched to the engine.

 

so with a cat which is properly matched, what kind of gains should one see?

 

Not sure, but since there's no record of anybody doing this on this forum I'll probably pony up the extra bucks to do a before/after dyno comparison depending on where I get it done.

Edit: A big portion of it will probably be determined by whether or not I can find one that is matched to the engine yet with less restriction. The factory cat is tuned to the engine AND will pass emissions. A replacement has to be tuned to the engine or else you lose power, and it also has to be able to pass emissions. Might not be able to find a cat that will do both, but I'll damn sure try!

 

Keep your old cat and slap it back on when it's time for emissions tests.

 

you have 3 options when your in a state that has emissions test

1. Dont do the cat
2. keep your old one and do a swaper when its time for emissions
3. pay the man b4 hand so not put the meter in the exhaust and youll pass for sure lol

#3 was very popular down here in miami FL thats one of the reasons they took that crap out

good luck hope it works

 

It depends which state you are in. In WA, you don't even need to start the engine for the emission test if the car is 1996 or newer (OBD2), and there is no visual inspection. They simply connect a tester to the diagnostic port of your car and look for stored codes.

 

That's all?

 

Whats an emissions test, inspection you mean?

 

meow!

jk. if they made a high flow cat - i would buy one.

meow.

oh no! watch out for the trout!

:troutslap meow.

 

No, they also check the gas cap to make sure it's working properly. Now, that's all.

Just imagine forced induction setup with Hondata K-Pro (OBD2 compliance) and still pass the emission inspection.

 

there is a custom exhaust shop around me that does custom cat converters, maybe it'd be worth a call to them

 

Or all you need to do is erase those codes from the ECU before you go there..

 

Actually, I believe they will know when the codes were last erased. So, if they do, they will fail you.

 

I might end up doing this. Of course, if I'm going to do that, there is the temptation to go balls-out and just drive with a test pipe on.

 

So to avoid being caught up all you have to do is have an extra ECU sitting around and there you go =)

 

Just got back from the shop. I'm going to have a 3" stainless steel Magnaflow put in using the flanges from the stock cat. The guy said it won't be a problem.

Emissions checks will work out fine since the TSX is an OBD2 vehicle. Here in Massachusetts, they check emissions on OBD2 vehicles by simply plugging into the onboard computer via the diagnostic port. Not by cornholing the exhaust system with a probe. So this means that, as long as the check engine light stays off, the car will pass emissions. At least while it still looks new and semi-stock - most sticker stations up here only do the more thorough checks on the kids with a billion stickers on their cars, or older looking vehicles, both of which stand a better chance at having an ECU that can't properly diagnose a malfunctioning converter due to tampering or age.

The bung for the downstream O2 sensor is behind the entire element on the Magnaflow, so the downstream sensor gets the exhaust gas that's been fully scrubbed by the catalyst. The stock cat has the bung about midway down, where the exhaust gases aren't yet fully scrubbed. This implies that there is a significant amount of leeway available for relaxing converter restriction while still remaining inside emission limits.

I'm going to have this done at the same time as a Comptech header and Hondata intake manifold spacer so gains attributed to this upgrade, if any, will be masked by the others. Hopefully I'll be able to get this some day next week.

 

Yes, it will work as long as the replacement is a true cat and the secondary O2 sensor is installed. Don't forget to do before and after dyno.

 

If at all possible I will do this. The shop just tore up their dyno because they're putting in a new AWD dyno for their EVO/WRX customers. If it's up and running by whenever I get my car in there I'll make sure to do it.