3 inch cat to stock DP?

[SinaiTSi]

I am planning on buying the 3 inch SS Buschur catback exhaust system with a 3inch cat. too. I just wanted to know if you can bolt the 3inch cat directly to the stock DP. Thanks a lot.

 

[tonygst]

no, not without modification or adapter.

 

[Mist3r Spool]

^ Correct. Most likely, a muffler shop can fabricate a flange to help you fit things together. Something like that shouldn't cost much.

 

[SinaiTSi]

I'm planning on doing the exhaust myself, so can I buy the flange online, or should I just go to a shop and tell them what I want.

 

[T2Small]

Having a sharp transition down from 3" to the stock size is not a good idea. Ideally you would gently transition from 3" down to stock. A flat plate (flange) is a very abrupt transition and will hurt flow more than simply having a stock setup.

 

[speedy13]

just have the muffler shop cut off the stock DP flange and weld on the cat to that,at least till you get a larger downpipe,then you can flange everything to match up nice nice and neat.

 

[SinaiTSi]

Having a sharp transition down from 3" to the stock size is not a good idea. Ideally you would gently transition from 3" down to stock. A flat plate (flange) is a very abrupt transition and will hurt flow more than simply having a stock setup.

Are you saying that by going from stock dp to 3inch cat and catback exhaust, it would have less exhaust flow than the stock setup? And if so, what do say is the solution.

 

[oldman]

Having a sharp transition down from 3" to the stock size is not a good idea. Ideally you would gently transition from 3" down to stock. A flat plate (flange) is a very abrupt transition and will hurt flow more than simply having a stock setup.

He's going from stock to 3" so it's ok but you're right, I would not recommend 3"DP to stock cat/cat back.