Stock cat replacement
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From: San Luis Obispo, CA
Stock cat replacement I was planning on doing a new exhaust setup with LT's and the whole bit, but I decided to go in another direction to stay legal with California SMOG laws. I have two brand new high flow magnaflow spun cats that I can't figure out what to do with.
Would it be worth replacing the stock cats with these if I am keeping my stock manifolds? Or am I better of selling these and putting my money elsewhere?
Thanks for any help.
Would it be worth replacing the stock cats with these if I am keeping my stock manifolds? Or am I better of selling these and putting my money elsewhere?
Thanks for any help.
if you replace your stock cats with high flow spun cats you are not legal anymore anyhow so if you are considering doing that you might as well install long tubes. Or leave it alone and sell the cats...that would be my choice.
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That's true, but I think the cats would be a lot less obvious than a set of LT's. I'm just wondering if there is anything to gain or if the stock manifolds are more of a restriction.
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You really can't replace the stock cats with those because of the stock cat is integral with the header pipe. If you figured out a way, you'd fail visual. I suppose you could gut the stock cats and install the Magnaflows in an aftermarked Y-pipe, but that would be a lot of work and expense for very few hp. Plus you may fail the sniffer.
The consensus on this board is pretty much "either go LT's or leave your manifolds and cats alone."
The consensus on this board is pretty much "either go LT's or leave your manifolds and cats alone."
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I'm not too worried about the guys getting in there and taking a hard look at the cats, but if there are some stainless exhaust headers I know that will attract enough attention for them to look closer so I want to avoid that. Although it looks like this will be a waste of time.
Looks like I'll just sell them and put the money towards new valve springs for the cheatr cam.
Thanks guys.
The stock cats are not that big of a restriction. From what I've read over the years the biggest restrictions in the factory exhaust is the muffler and the manifolds. So replacing if your not planning on doing LT's I would invest the money elsewhere.
I was in your same position but moved away from Socal earlier in the year. I have the JBA shorty with stock cats mated to the better flowing SLP y-pipe and a Magnaflow system out the back. I went with the purchase 2 years ago of buying the Magnaflow Direct Fit replacements cats because they were rated as a higher flowing cat then the restrictive stock units. Never the less, they are still sitting in the original unopened boxes. I am now considering going the long tube route myself, but at the cost to HP increase, I am still debating. Also, if I keep the car and some day move back to Socal, I will no longer be smog legal and thus spend the $$$ again...ouch!!! My thoughts are yours too in this regard.....
nope. 
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Unfortunately, there is not anyone that makes a set of CARB long tubes. Relocating the stock position of the cats is illegal and thats what the long tubes do.
I have a cheap set of long tubes for sale, PM me if you're interested.
I would if I didn't mind risking a huge fine if I get pulled over and the cop looks for cats.
^^^ This is a damn good idea. I think this is the way to go. I'm interested if it will add any rasp, at least I could switch back to the good set.
I was in your same position but moved away from Socal earlier in the year. I have the JBA shorty with stock cats mated to the better flowing SLP y-pipe and a Magnaflow system out the back. I went with the purchase 2 years ago of buying the Magnaflow Direct Fit replacements cats because they were rated as a higher flowing cat then the restrictive stock units. Never the less, they are still sitting in the original unopened boxes. I am now considering going the long tube route myself, but at the cost to HP increase, I am still debating. Also, if I keep the car and some day move back to Socal, I will no longer be smog legal and thus spend the $$$ again...ouch!!! My thoughts are yours too in this regard.....
^^^ This is a damn good idea. I think this is the way to go. I'm interested if it will add any rasp, at least I could switch back to the good set.
or, gut the OLD ones, and put them on. then if you need to smog, THEN put the new ones on. dont know about the rasp though.