I need a high flow cat for my 00 civic si and was wondering is there a flow difference between different companies. What I'm trying to say is should I get a universal catco from summit racing for like 50 bucks and take it to a muffler shop, or get a direct bolt in like carsound, powercore or random technology. Also is one better than the other? I've noticed the universal catco is $50 and the direct catco bolt in is $150, or should I spend $220 on a random, carsound, or powercore cat ????? BTW I'm not doing a straight pipe, car is N/A and has to pass emissions. thanks for all the help in advance

 

Anyone please??

 

Unless you're doing this to bolt up to a header with a 2.5" collector there's no gain to be had. The stock cat isn't a restriction with a stock sized header unless the cat is old and has filled itself up with smog particles. Your car isn't old enough for this to have happened yet.

 

Have you ever actually examined a stock Si cat.? The stock cat is pitifully small and restrictive, and replacing it with a high-flowing cat. will indeed result in gains. Just how large those gains will be will depend upon the particular car's setup, but to say that the stock cat. is not restrictive, even when running the stock exhaust manifold, is simply inaccurate.

 

Yes, there is a difference. I don't know all of them so I can't help there.

BUT, I chose the RandomTech cat for my application (3" cat) because they offered me a 5year warranty on the core.

 

O sorry I forgot to mention this will be between a dc header and an apex n-1 cat back, the engine will be N/A.

 

Try talking to Dave at SMSP. He'll be able to build you a cat. to any specifications you need, and I'm sure he'd be more than willing to answer any questions you might have. You'll find that having a muffler shop install a universal cat. will be similar in price to a comparable custom cat. from Dave, and Dave's quality and customer service are first-rate. I stress comparable because Dave uses high quality materials and does very-high quality work, two things that a low-priced muffler shop, while cheaper, might not offer.


[Modified by Padawan, 1:52 PM 12/31/2002]

 

So is there any proof (flowbench) that the stock cat really doesn't flow that well?

 

There was indeed a thread that existed a while ago (which I was unable to locate with the search) listing the flow numbers for certain aftermarket cats., stock cats., and test pipes. The numbers indicated that the stock cats. flowed significantly less than the majority of the aftermarket "high-flow" versions.