Ok boys and girls, I have to replace my front catalytic converter. I figure that while I'm down there, I am eventually going to want to upgrade the entire exhaust system. Why change only 1 part of the equation while leaving the other completely stock.

This modification will include a new set of headers, 2 high flow catalytic converters or just 1 if that can be managed, delete the resonator, and have it make its way to the back as smoothly as it can, ending with a nice high flow muffler. The goal is not to have it sound like a Honda. I would like to think we're above them.

I'm not sure of the stock diameter of the pipe, I'm assuming 2". What suggestions do you all have? Let's scavenge those cylinders!! I know we're not going to gain 50 HP but who cares?

 

Keep the second cat and do a header. As far as diameter pipe don't go over 2.25.

 

Why is the second cat needed? Isn't that hindering the flow rate, or is it because it's just simpler for ECU/MIL purposes?

 

It's for back pressure

 

The 2nd cat is for Cali compliant. If your stock I would suggest headers with something like the greddy cat back if you want a decent sound for NA. Your call on either a HFC or leave it. What you can also do to keep it simple is do headers/HFC/Catback and have a shop put an o2 bung after the HFC this will prevent the cel light when you remove the first cat in the stock headers.

 

I've got a greddy evo2 cat back and it sounds great. O ya and I have headers and a cat delete pipe. I want to try a hfc but I don't need cats where I live.

 

I've been talking to a few people and they're basically suggesting that I get a 2.25" inlet/outlet headers with the high flow catalytic converters, and a high flow muffler. Not sure which muffler is going to offer the most CFM's as most manufacturers that I have seen do not post their ratings, nor can I find the stock CFM rating for the stock muffler. :/

 

Your n/a you don't need hi flow. You need a balance this isn't rocket science. Turbo = you want least resistance. Nothing na will give you more then 5-10 whp n/a buy what you think looks best and sounds best.

 

I seconded that most manufactures have videos of there exhaust and what they sound like. So that's a good way to find something you like

 

Don't delete both cats or run 1 high flow, it sounds like ***, I personally run no cats and it is terrible. I had to put a 24" resonator in and its still awesome. I am clueless at this point except going back to stock as much as I can.

 

I don't care what it sounds like, I just want to scavenge more power. What I don't want is for it to sound like every 97 Honda Civic DX on the road or a Subaru STI.

For those of you that live in Utah, I am slowing down in 4th gear and even damn 3rd gear at a certain point on Parley's Summit on I-80 going to Park City. I used to be able to hold my ground in 4th gear at a point. Not anymore. :/

 

be very careful when seeking power through exhaust modification...you won't get much, but if you maintain a certain pressure differential between the intake manifold and exhaust you may be able to squeeze a few ponies, if you feel it, that's your wishful thinking telling your wallet that it's ok j/k, but really, don't just slap on pipes with bigger holes...people call it "back pressure" but really it's the difference in pressure between intake and exhaust.

 

x2 you won't be able to measure it. It will not give you a noticeable increase.

 

Haha I know right?? I wonder how much HP is lost from having a clogged cat. In any case, I can't wait to get it replaced. If I don't have to go into third on the hill, I'm calling it satisfactory.

 

http://www.pepboys.com/product/detai...ic_converters/

So this is what I ended up purchasing. They're a respectable name and so it's just the converter instead of a header.