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Discussion Starter #1

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Stock exhaust is 3.5". The 4 bolt flange SHOULD be the same....but I dont know how it would work out. If you were closer, I would sell you my old front pipe.
 

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Yeah I am looking to eliminate the cat with a one piece replacement pipe. I don't want to use a flex pipe or anything.
 

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I would say that it must work...i just dont know if you would have an exhaust leak there over time. I know they made cat-back systems that bolted...but going from 3.5" to 4" is better than going 4" to 3.5". There will be someone on here that has done exactly what you are doing...but I think what was intended was for the people that wanted to go cat-back and then delete the cat...and put it back in when they had inspection. You might want to check a salvage yard or ebay for the factory frontpipe...you could probably get it pretty cheap....shipping would kill you if I sent mine to you though.


On edit you can contact PTP and they will be able to answer your question for sure.
 

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Discussion Starter #6

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So there would be a 4" from pipe and then it would mate to my 3.5" stock "cat-back"? Is this going to cause an obstruction of flow...?
That's correct, it'll bolt up like Chad said. I installed one of these that came from Chad onto an LLY a few days ago. I think you'd be just fine with it, but yes it'll abruptly go back down to 3.5", might be best to go to a full 4" kit.
 

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Discussion Starter #8
Is there an easy what to eliminate the cat in a stock exhaust..? The muffler is already eliminated.
 

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Yeah find a LB7 frontpipe....or if you dont care about having a cat for an inspection...take off your cat and cut the pipe and weld a piece of 3.5" pipe there.
 
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