Gutted catalytic converter?

[jbillakdsm]

Hey guys, I just picked up a stock cat for my car b/c I need one to pass inspection and emissions. I'm going to be putting it on a 2.5 turbo-back and I'm making slip-fit adapters for the ends. My first question deals with flow. Is there a significant difference between a gutted stock converter and a 2.5 high flow? I'm assuming the stock will be less, but is it enough to make a noticeable difference in power. My other question has to do with emissions. If I gut this thing, am I still going to be able to pass emissions? I live in PA so any help from the locals would be great. I know I should just buy a 3" high flow and be done with it, but I don't have the money right now so I'll just deal with it till the funds come around.

 

[nine5raptor]

if they do the "sniffer", then you probably won't pass. if it is a visual inspection, cut the cat then put a straight pipe through it so it looks like a real cat (I've heard of people just hammering the pipe through the cat and then cleaning out the pipe). or you could put the heatshields from the cat on the test pipe to make it look real. I just swap the cat back in for a day or find a 'shadier' inspection place that will point and laugh at the test pipe, then slap an inspection sticker on the windshield.

 

[jbillakdsm]

Yeah, they do the "sniffer" here. I don't know if you have to pass HC and CO2 here or not. My old car was registered in a different county, so I didn't have to pass emissions. Does anyone out there know what the stipulations for emissions are in Pittsburgh?

 

[ECLIPSE4x4]

Here is what I do. I run a test pipe all year until inspection. Then I put on a cat that I have. it takes only a few minutes. Get the emissions test and inspection, then back to the test pipe.

Save the cat, don't destroy it for no reason. Get a test pipe made, they are relatively cheap and straight through flow.

 

[jbillakdsm]

Yeah, I have a testpipe already, but it's fitted with flanges. I was going to just cut the flanges off the whole system and make it slip fit. I just don't know where I can get 2.5" exhaust flanges on short notice without costing an arm and a leg. I also have to buy expander pipe for both ends of the stock cat., weld them on, and make sure I get the length right on top of extra gaskets. The car goes to the dealer on Friday for Xfer case replacement and I need to get it all together to go on by then.

 

[nine5raptor]

any exhaust shop should have the flanges and could modify the cat for you. they should have the gaskets as well.

grab a phone book and call around

 

[jbillakdsm]

Yeah, the only problem is that I live right in the city and shops charge you way more. I called some today and I could buy a new cat for what they wanted just to put expanders on each end, cut it to the right length and weld on the flanges. I think I'm going to weld the extenders on this weekend myself and wait till the car goes for re-inspection and have the guys there line up everything and then weld the flanges on so I know it will fit. Plus it will be a lot easier than me crawling underneath to do this myself. Oh yeah, it's a balmy 4 degrees outside right now.