Logan24

Hi, I'll be getting a Si/Do exhaust installed in the next few weeks. This is going to be a completely custom job, I am having a shop make the pipes from scratch. I am just wondering if its possible to have them remove the Catalytic Converter and weld the new pipe from there on with the stock headers. Now if it is possible, will it be an increase in power? What exactly would it do to the sound/performance of the truck??? Thanks in advance

PS. Let me know what exhaust you'd get and why. I'm leaning towards Borla or Flowmaster. Had the Flowmaster "kit" on my 06 and it had a bad drone at 110km/hour....

Koolponycar

I don't know about where you live, but here it is illegal for any shop to remove the cats due to emission laws. We have to go through an emissions testing everytime we get tags. I'm sure it can be done and you will probably see an increase in horsepower, but you will have the computer to deal with in order to make your truck run properply and not have codes and check engine lights appearing. You will probably have to reflash the computer and as new as your truck is if you take it in for warranty work with the cats gone they probably will void your warranty. Someone else may know how to get around this, I wish I could remove mine too. Borla and Flowmaster are good sounding exhaust with a lot of variety to choose from. I went with flowmaster 40 series 3" SI/ 2.5" DO. Here are a couple of clips, good luck

Abn Scout

You are right on both counts. It would improve performance (did it before a long time ago.....different planet then). But it is straight-up, no doubt illegal to do it. You wouldn't be able to get a legal inspection performed and pass due to emission standards.

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obusnizzle

I wouldnt touch a flowmaster muffler, even if it was free. I live in the salt free southeastern united states and had a set of 40 series rust out in under two years. Now, Canada has some pretty abusive weather....snow, road salt, etc...I would get a stainless muffler and tubing. I would get a Borla.

I wouldnt bother with cutting the convertor, its going to be quite a bit of work and more money for a minimal gain. Not to mention, you will have to have the function for a MIL turned off in the EEC.

Deftones

I would go with Magnaflow Stainless Steel SI/DO kit. If you want custom you should get a true duel kit fabbed up. The Magnaflow kit I have took me only 1 1/2 hourss to install myself in my garage with simple tools.

Koolponycar

SALT FREE! You live in Florida where you are exposed to salt air from the ocean,so I wouldn't say it was all because of the aluminized muffler. You can get a flow master in stainless,their stainless part numbers start with the number 80. But stainless tubing will last longer. Borla is a great kit,and should be for the cost. Their are a lot of other stainless kits for less,just depends on what your willing to spend and what you want.

obusnizzle

thanks for trying, but actual rust on vehicles are rare outside of direct exposure. Aside from surface rust and basic oxidization from surface iron content, it doesnt happen. 2 years into owning a set of mufflers, they shouldnt have holes in the weld lines.

I mean, sure I could go about how there is dynoed proof that Ford modular motors respond better to flow through mufflers, than baffled ones, but hell...what do I know.

Koolponycar

Sorry, didn't mean to offend you. I figured the salt air may have progressed the rusting, but like you said no muffler case should rust in the weld lines or anywhere in just 2 years. Most rust from the inside out from the condensation produced inside the exhaust. This is only my second set of flow masters, I had a 50 series on my first truck for 5 years and no rust when I got rid of it. I am not a diehard flow master fan,but have used other aluminized mufflers also with good results over a 3-5 year span. I always spray my welded joints with etching primer also to keep those from rusting on the outside. Maybe you got the Friday night special LoL Just kidding. When a person has A bad experience they tend to stay away, I can understand that. I chose these strictly for sound, and like most will end up changing it down the road when I get tired of it. My second choice was magna flow. If it wasn't so expensive I liked Corsa most.

Logan24

Thanks a bunch guys, I
like the info!!!
Just got off the phone with the shop and they said hell no when i asked. They basically said they would be in huge trouble if somebody found out, not to mention me...lol
As for the guys who mentioned the "kits" I am not going that route with this truck as my 06 had the Flowmaster 50 series i think. It sounded great but that drone annoyed the hell outta me. For that reason I'm leaning heavily towards Borla and thanks to you fine gents I will insist on them using stainless tubes!!!
Thanks again guys, if anyone else has some input I'd be glad to hear it!!

Logan24

Well, after a heart to heart with a buddy that has had more trucks than girlfriends I was talked into a magnaflow system. It's getting welded on the truck as I type.

Thanks again for the help guys.