hi-flow cat or keep the stock

[pfdog1]

Is a high flow cat just a waste a money? Is our stock cat already high flow with just a smaller outlet? These are the remarks from an earlier post I saw when I did my search. I've got 2.75" s-pipe and i- pipe from a 93 LT1 stock catback getting trucked in tomorrow. When it gets installed in my v6 in a couple of weeks along with my high flow muffler and tips I have to decide if I want the catco 6007 installed as well. Acccording to my muffler guy the catco#6007 isn't even a true high flow cat just a direct fit replacement for stock. Seems like a waste if it doesn't do that much except set off your engine light. According to this same person, the engine light will go off when the exhaust flow is restricted or when there isn't enough flow, never the other way around. I don't know who's right.

[Dan M]

As far as I've heard, our stock cats are 3" IN and 2.25" out. Unless he is an f-body specialist, I see how he might get confused. Catco #6007 is 3" all the way through and X happy customers on this board can't be wrong.

The guy that put my muffler on for me told me that all high flow cats were a waste of money. Shrug.

[Arctc Wolf]

all cats r pretty much made the same, so they're all high-flow, it's just the outlet diameter's are different. ours isn't too restrictive, but once u get a bunch of intake mods done 2 the car, it can be. it's worth doing if u plan on doing all the basic bolt-ons, and can only help if u r gonna do heads/cam sc, nitrous, turbo, ect.

[pfdog1]

<blockquote>quote:</font><hr>Originally posted by DrSquirts:
As far as I've heard, our stock cats are 3" IN and 2.25" out. Unless he is an f-body specialist, I see how he might get confused. Catco #6007 is 3" all the way through and X happy customers on this board can't be wrong.

The guy that put my muffler on for me told me that all high flow cats were a waste of money. Shrug.<hr></blockquote>

seems like half the postings I read on those that have installed the 3" indicate some chronic issue with the engine light that isn't always corrected with the O2 sim install. I'll be checking with my dealer on possible warranty void violations with the cat install as well. Looking for more of a compelling arguement to do this, performance, exhaust sound standpoint, anything. Seems that there are too many reasons not to do this than otherwise. I suppose I could just stop short of the cat for now, seems a shame though. If good fine if not I'll swap it out.

[BillyCobin]

The mechanic is sort of right. If the exhaust becomes clogged, it can trip a SES light. He is also right that if the exhaust is completly free flowing, it will not trip a SES light. The only problem is that the computer monitors your exhaust with an O2 sensor after the cat. So if you remove the cat, or don't plug that O2 sensor into the exhaust, it will trip a SES light.

I have a catco 9007 (it's bigger than the 6007) installed, and have had no problems with it. The exhaust shop just cut the old one off, and stuck this one in, without touching the O2 sensor. I really like it and recomend it. It made my exhaust a little louder, and little deeper. I can really feel the power it freed up above 4k rpm.

[pfdog1]

Thanks I'll look into it. In fact that is what he was recommending, the catco#9007 for super huge engine sizes it would seem. I didn't know anything about it so I didn't agree with him just wanted to stick with what everybody else was doing, i.e., #6007. I think it's the same 3/3 in-out just overall longer than the 6007 by a couple of inches.