Bolt in resonator to replace second cat?

Mid_Life_Crisis

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2007 MS3
Many of us would like to remove the second cat, but not all of us want the increased noise. Is anyone marketing a bolt in resonator to replace the second cat? Reduced restriction with minimal noise increase?
Seems like this shouldn`t be that expensive a part.
 
I'm sure any exhaust shop could easily do that. But I don't think just taking one cat out makes that much of a volume difference. It improves the tone of the exhaust in my opinion, but not volume.
 
I'm sure any exhaust shop could easily do that. But I don't think just taking one cat out makes that much of a volume difference. It improves the tone of the exhaust in my opinion, but not volume.

Problem is that under federal law it is illegal to do it, so not all shops are willing. I was hoping for something I could do in the driveway that wouldn`t break the bank and would be reliable.
 
Look at my mod below. I put a straight through Vibrant UltraQuiet 3 inch reso in the middle of my TurboXS race pipe. I don't know about race pipe noise alone, but with the combo of dp/rp the drone at 2500 rpm was really bad. The reso fixed this without harming flow.

What I had to do was cut the rp and remove enough of the middle of it to allow for the reso and still have the rp the exact length to match up with the dp and the CBE. This part is simple hack saw work and careful measurement. The reso will fit over the 3 inch TurboXS rp, so you can make adjustments in length and angle with temporary muffler clamps. Leave enough on each end for the reso to slip over. Once it is all aligned right, you can then take it to a muffler shop and they will spot weld, remove the clamps and then complete the welding. They will not know that this was replacing a cat. They don't know what you are connecting it to. They just have a pipe, flanges, a reso and some clamps.

Just a thought . . .
 
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ive though of this in the past but everytime i think "rice" but what about a high flow muffler like an hks or the greddy how would that do?
 
ive though of this in the past but everytime i think "rice" but what about a high flow muffler like an hks or the greddy how would that do?

A good stainless straight through reso should be (1) smaller and lighter (2) less restrictive (3) cheaper and (4) more appropriate for tuning out the droning that comes with taking out the second cat, IMHO, than trying to put a high flow muffler in that relatively short, cramped section of the exhaust system. Very "anti-rice" stealthy approach.
 
Look at my mod below. I put a straight through Vibrant UltraQuiet 3 inch reso in the middle of my TurboXS race pipe. I don't know about race pipe noise alone, but with the combo of dp/rp the drone at 2500 rpm was really bad. The reso fixed this without harming flow.

What I had to do was cut the rp and remove enough of the middle of it to allow for the reso and still have the rp the exact length to match up with the dp and the CBE. This part is simple hack saw work and careful measurement. The reso will fit over the 3 inch TurboXS rp, so you can make adjustments in length and angle with temporary muffler clamps. Leave enough on each end for the reso to slip over. Once it is all aligned right, you can then take it to a muffler shop and they will spot weld, remove the clamps and then complete the welding. They will not know that this was replacing a cat. They don't know what you are connecting it to. They just have a pipe, flanges, a reso and some clamps.

Just a thought . . .


This is the best option and should be doable for under 200 bucks. Once the race-pipe is installed, just take it to a shop and request the pipe be cut out and replaced with a resonator.
 
A good stainless straight through reso should be (1) smaller and lighter (2) less restrictive (3) cheaper and (4) more appropriate for tuning out the droning that comes with taking out the second cat, IMHO, than trying to put a high flow muffler in that relatively short, cramped section of the exhaust system. Very "anti-rice" stealthy approach.

yeah the last thing i want on my car is a rice paddy to where i start to blend in with the bad civic group hahahaha
 
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