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Old 03-29-2009, 07:51 PM   #1
Mister laugh
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High Flow Cats

Well i think i need some new cats on the truck i bought about a month ago. Looking into it it turns out a set of cats for the vortecs runs about a grand. Not wanting to spend that much on something stock i decided to look at high flow, magnaflow sells a system for about 1600. Definitely not wanting to spend that much i discovered some magnaflow high flow universal fits on ebay for roughly 100 each shipped, that sounds a bit better. Now my question is what do i need to know before welding a new set in? I have welded muffler pipe before so i know its a pain in the ass. Or am i just better off gutting the cats i have if i don't have emissions here?


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Old 03-29-2009, 08:37 PM   #2
cdowns
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Re: High Flow Cats

my cats are envirmently friendly
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Old 03-29-2009, 10:06 PM   #3
Palf70Step
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Re: High Flow Cats

The dual cat setup on the Vortecs are pretty efficient. I am assuming you are talking about your 2000 with the 4.8? How many miles on yours?

We swapped out a guys at work for some from the Vette, but I think we got more out of the Catback system, than we did out of the cat swap.

Oh when we swapped out the cats, the computer needed also needed reprogrammed to take advantage of the changes.
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Old 03-29-2009, 10:36 PM   #4
Mister laugh
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Re: High Flow Cats

Quote:
Originally Posted by Palf70Step View Post
The dual cat setup on the Vortecs are pretty efficient. I am assuming you are talking about your 2000 with the 4.8? How many miles on yours?

We swapped out a guys at work for some from the Vette, but I think we got more out of the Catback system, than we did out of the cat swap.

Oh when we swapped out the cats, the computer needed also needed reprogrammed to take advantage of the changes.

I don't doubt there efficiency, but mine are plugged, and new ones are 1000, where as i can pick up a set of magnaflows for 200ish and weld them in, it seems alot more economical to me.
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Old 03-30-2009, 09:02 PM   #5
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Re: High Flow Cats

You would get the same effect with the universal cats as you would with the OEM replacements.

Also if you take them out, the computer will have to be programmed with the rear o2 sensors turned off. CEL will be on if not.
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Old 03-31-2009, 06:59 AM   #6
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Re: High Flow Cats

I put dual exhaust on my`90 Blazer using Thrush hi-flow catalytic convertors.They were still good at least 10 years later when I sold the Blazer.They were $100 each.The vehicle ran way better with the duals through those convertors.
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