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High flow cat or oem

Discussion in '3rd Gen 4Runners (1996-2002)' started by Lucky4runner, Oct 11, 2021.

  1. Oct 11, 2021 at 5:41 AM
    #1
    Lucky4runner

    Lucky4runner [OP] New Member

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    So can anybody give me any advice I really would like to increase the flow but not so much to where I'm losing needed back pressure is anybody have any suggestions I see a lot of cats online for like 130 bucks direct fit and it sure is a lot more appealing than the $1,000 cost for OEM ones Walker and a couple brands like MagnaFlow flowmaster anyone have any suggestion
     
  2. Oct 11, 2021 at 6:51 AM
    #2
    suaveflooder

    suaveflooder New Member

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    Is it necessary, or are you looking to upgrade?

    from my experience, cats that are not OEM don’t last long. But the last time I put a high flow cat on was years ago, so they may have gotten better
     
  3. Oct 11, 2021 at 7:10 AM
    #3
    SlvrSlug

    SlvrSlug Slightly bent.

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  4. Oct 11, 2021 at 7:48 AM
    #4
    McSpazatron

    McSpazatron New Member

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    I would avoid aftermarket cats, especially if they are going to be welded on in place without removal of the whole exhaust system. It’s hard to guarantee a good weld if it’s done in place, so you’ll probably get leaks there. Also, the cats themselves will fall apart internally in a few years time unless you are spending OEM levels of money (and even then, OEM is probably still better).

    The entire OEM exhaust systems in modern cars are extremely well built and can last well over a decade. Aftermarket is not usually as well engineered.
     
  5. Oct 11, 2021 at 8:14 AM
    #5
    Lucky4runner

    Lucky4runner [OP] New Member

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    Thank you no yeah it's necessary mine's plugged so bad you can barely feel any exhaust pressure coming out the tailpipe it's a direct fit so it just bolts on where the two goes into one right before the O2 sensor and then right back behind it before the muffler like it's been a long time but I saw people a long time ago talking about like Walker and I can't remember the other one saying that they were decent if you guys know anything about those I appreciate the Intel
    P
     
    suaveflooder likes this.
  6. Oct 11, 2021 at 8:16 AM
    #6
    Lucky4runner

    Lucky4runner [OP] New Member

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    Is anyone familiar with any markets that sell maybe used OEM cats that aren't you know totally gone I've looked on offer up and I've talked to you but they're not for 4Runners they're for like a Corolla stuff like that exhaust is just one area of the whole mechanical side of vehicles that I'm not familiar with other than the fact it can be expensive and I can't do it myself LOL
     
  7. Oct 11, 2021 at 8:19 AM
    #7
    McSpazatron

    McSpazatron New Member

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    Sorry, thought I was on the 5th gen forum. Yeah sounds like you are in need of a cat, so carry on ;)
     
  8. Oct 11, 2021 at 11:28 AM
    #8
    PhantomTweak

    PhantomTweak New Member

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    None. Bone Stock. EXCEPT: Brushguard, tow hitch, both welded to the frame. It's good to have friends and a fully equipped garage!
    Try taking a ballpeen hammer, and beating the &^%* out of your cat(s). Not enough to dent it, but just short of that. I've been doing that once a year or so, and mine are all still working great. In fact, every time I do, I can hear the difference, and smell it as well.

    The guy who told me to do that was a professional mechanic at my last job. Knew a lot of little tricks. Of course, he told me the best thing I could do for the cat was to take it off, shove a big standard screwdriver down into it, wave it around a lot, dump out the results, and put it back on the truck.
    He wasn't real big on smog reduction stuff, and in Yuma, a pickup or 4Runner wouldn't make a noticable difference in the air quality. Lots of heavy farming work, burning off old fields and groves of fruit trees, and the air was almost as bad as LA.

    Just an anecdotal piece.
    Have a good time!
    Pat☺
     
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  9. Oct 12, 2021 at 6:42 AM
    #9
    negusm

    negusm New Member

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    I would go get OEM, I know they are super expensive but they have like 3 times the material that an aftermarket CAT does. The aftermarket CAT will work for a few years and then you'll be back into looking for another one. It won't plug up, but you won't pass smog.

    If your CAT plugged up this bad, I would look at doing an in-depth inspection of your engine. What's your compression like? Plugs look good?

    My CAT is 20 years old and shows no signs of plugging up so far. Of course, tomorrow, it could do just that. Maybe I need to start banging on it.
     
    suaveflooder likes this.
  10. Oct 12, 2021 at 8:09 AM
    #10
    suaveflooder

    suaveflooder New Member

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    quick fix, head to an exhaust shop. I think they are $80-$100 each. But as mentioned above, something is causing it. You just need to figure out why. Then go OEM. You will spend the money, but they shouldn’t clog
     

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