Installed 01 Cat-Back on my 03 Cobra

[PacWest]

I just installed an 01 Stock cat-back on my car. I was able to get it brand new at a good price. I put it on because I trashed the Steeda Cat-Back I had on the car when it was too low. I hit some steel plates in the road and wiped out my Steeda mufflers. That's a different story but I've since fixed my ghetto suspension setup.

The 01 fits perfectly and I like the tips better than the stock 03/04 setup. It sure is nice for trips on the freeway - nice and quiet inside. Here are my observations for anyone considering this.

1. The car seems slower compared to my Steeda cat-back. I doubt it really is but it's quiet and that makes it seem slower.

2. The 01 cat-back has a better sound than the 03 stock cat-back but it's still quiet.

3. I don't hear my supercharger as much as I did before. Strange, I thought I'd hear it more.

4. The 01 fits up under the car a LOT better than my Steeda did. I have a lot more ground clearance. Those Steeda mufflers are narrow and fat and hang down low.

So now I have to make a decisoin. I have 2 perfect mufflers out of an FR500 cat-back. Should I have them welded in to my 01 stock cat-back? I think I will just to see what it's like. I would like to have it louder when I'm WOT and I'm sure the FR500's must perform better than stock.

I wonder where the restriction is in the stock cat-back...my guess is that it's %70 mufflers and %30 in the smaller pipes but I don't really know.

-Ryan

 

[addicted2boost]

The stock catback is more restrictive partly because the pipes are not mandrel bent. For example put your hand around one of the bends of a stock catback and then around the same bend on a mandrel bent aftermarket catback and you will definatly be able to feel a difference.

The stock mufflers are also restrictive. Some of this restriction comes from their quiet design. They are also restrictive because they are actually less than 2.5". I read the exact dimensions somewhere on the forum but I know it is close to 2.25". When I had a muffler shop weld 2.5" flowmasters into my stock catback they were actually able to slide the flowmasters over the outside of the existing pipes.

What do you have left of your steeda catback? My suggestion would be to have a muffler shop weld in the FR-500s into your steeda catback rather than the stock one.

 

[moonltgold]

Weld in the FR500s

What do you have left of your steeda catback? My suggestion would be to have a muffler shop weld in the FR-500s into your steeda catback rather than the stock one.

Ditto. That's the best solution.

 

[PacWest]

I tried that before I bought the stock 01 cat-back. The mufflers are a different shape and they did not fit - they hit the frame rails. I think a better shop could have made them fit. However, I did not want to put too much money into it considering that I could probably get a used maggie cat-back for about $300.

Thanks for the ideas.

 

[porktyme]

Hey man, I have FR500's welded into 01 pipes. It's a very nice setup. There is almost no difference between these pipes and mandrel bent aftermarket, I have actual data to back up that claim.

There is a slight drone at 1800-1900 RPM which is about 65-70 on the highway. I developed a custom noise attenuation device that goes before the muffs and eliminates most of the drone without sacrificing performance.

The restriction in the stock catback is in the inlet and outlet of the mufflers. It necks down to 1.93" ID to keep the noise down, but creates a great deal of flow restriction. That's the problem in a nutshell.