x2 ..totally agree, imo if less power is noticed afterwards is because air/ fuel ratio hasn't been optimized for the loss in backpressure

 

So has anyone here passed a sniffer inspection with a gutted cat? I was thinking about buying a high flow universal and replacing my old one with that since its cheaper than a stock one.

 

You wont be able to pass emissions with a gutted cat. And im nort 100% sure but I dont think you can pass with the high flow. I have even heard from one guy that said he replaced his with oem and failed emissions because he had it tested right after it was installed. He said he had to run the truck for a little while then take it back.

 

Pressure=resistance to flow

 

Well I'm not testing it til its due in March, but I need to fix some exhaust stuff, so I figured replace the cat while I'm there, because I think its broken internally.

 

Yes I pass my city emission tests. I had hollowed out my cat about 8 years ago or so. Every 2 years I need to retest, every time it passes. I have a strong clean burning engine.
Also it passes the visual inspection of a cat installed, but if the tech wants to be an A$$ about it sounding hollow they may fail it.

But just like every vehicle is different it may not work for everyone.

 

WOW I never would have thought that a gutted cat would pass inspection.

 

drag racing and real world vehicles are different animals. To big exhaust and you lose backpressure which drops power, to little exhaust and you choke it off. Find the sweet spot and roll with it.
I needed a new manifold/cat for my Civic and after a lot of research it came down to not screwing with the factory. If I put anything on it other than factory spec it would lose power and fuel mileage.
A V8 is no different. These Dakotas can be made to be better but unless you are going with more power putting a big high flow exhaust on them will be a detriment. They need backpressure to run correctly. Otherwise you will find the computer is having a hard time adjusting and can give bad reading from the 02, AIC, and other sensors.

Where backpressure is located is also important. But for factory vehicles, don't screw with the A/F ratio to much.

 

Unless you have 92-93 manifolds on your 5.2 the your killing your exhaust and should go with headers. As for pipe size if your staying stock with a y pipe have a custom 2.5 inch y pipe made. If your doing true dual exhaust the go with 2.5 from headers back. If you do true duals and want a h-pipe wait until after the duals are on and take a crayon and draw a line down the exhaust pipe and start the engine, where the crayon stops melting that is where you want your h-pipe to go. The h-pipe will help equalize the exhaust gasses and help pull the exhrout with a vacuum affect. Ive done a ton of research and have talked to a bunch of people that have been building the magnum series since they came out in 92 and this is what ive been told by several notable people.

 

Here is a link that may change your mind for your civic
http://www.importtuner.com/features/...l/viewall.html