Testarossa Catalytic Converter 121385: where to find? | FerrariChat
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Testarossa Catalytic Converter 121385: where to find?

Discussion in 'Boxers/TR/M' started by alex_kay, Apr 19, 2024.

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  1. alex_kay

    alex_kay Karting

    Apr 7, 2024
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    Central Switzerland
    Full Name:
    Alex
    #1 alex_kay, Apr 19, 2024
    Hello,
    turns out one of my catalytic converters is a bit closed. Not too much, I can still drive. But my shop thought it would be good to be on the lookout for one to change it when the next big engine-out service comes along.

    Do you know of any good sources where I can find a good used one?
    I already checked google and contacted Red Bay in Belgium and Koenig Specials. Neither has one. And aside from that I am only finding new ones.

    Hope someone can help me out.
    Best, alex
     
  2. Veedub00

    Veedub00 F1 Veteran
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    Jun 30, 2006
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    #2 Veedub00, Apr 19, 2024
    I wouldn’t drive it with a partially burned up cat. I’d investigate if something caused to get that way, like running too rich or too lean. Also these are the precats right?

    In Switzerland do you even need the cats?
     
  3. ferralc

    ferralc Formula 3
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    Sep 2, 2010
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    San Diego CA
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    #3 ferralc, Apr 19, 2024
    I am almost positive I saw some used cats for testarossa for sale here somewhere, scroll down the ads, it was an ad for several things and one of them were both cats.
    If not here in the UK there’s an alternative at a reasonable price (supposedly in stock)
    https://www.ferrariparts.co.uk/part/ferrari/121385?id=85069


    Sent from my iPhone using FerrariChat
     
  4. Capt. Rich

    Capt. Rich Formula Junior
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    Jun 9, 2008
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    Richard Baumgart
    #4 Capt. Rich, Apr 19, 2024
    Hey Alex_kay, If your cats are the same as a 512TR, I have 2 in good shape.
     
  5. alex_kay

    alex_kay Karting

    Apr 7, 2024
    79
    Central Switzerland
    Full Name:
    Alex
    #5 alex_kay, Apr 20, 2024
    @Capt. Rich Thank you for the offer. Do you have a parts number? I think the cats are different between the TR and 512TR, but let's see.

    @ferralc Thank you for the link. Where did you see the ad for both cats? Here on the forum? The only one I found was already sold unfortunately. The price was good, USD 400 for two cats.

    @Veedub00 Unfortunately, yes I need the cats in Switzerland. Would love to get rid of them. But I think best is to just change them. I saw on an old invoice of the previous owner that they put in two used cats back in 2020. It was done by an official Ferrari shop here in Switzerland. So I don't know if the one partially closed cat was always like that or if it got that way
     
  6. turbo-joe

    turbo-joe F1 Veteran

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    #6 turbo-joe, Apr 20, 2024
    I would replace the both old CATs and put in new ones only for the smog check and the MFK and the just put them out again and use only 2 straight pipes. store them and next check out them in again
     
  7. Capt. Rich

    Capt. Rich Formula Junior
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    #7 Capt. Rich, Apr 20, 2024
    Here is the number 512TR part #'s 149304
     
  8. bernieb

    bernieb Karting

    Apr 16, 2007
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    Bernard J Bonertz
    #8 bernieb, Apr 20, 2024
    I think I might have a pair in my back shed...can't remember if they came back after I went to Fuchs from headers back. Most likely they did. From a 1990 model Testarossa, I can check if I do indeed still have them. They would be for sale but I'm in Alberta Canada.
     
  9. alex_kay

    alex_kay Karting

    Apr 7, 2024
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    Central Switzerland
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    Alex
    #9 alex_kay, Apr 21, 2024
    @Capt. Rich Thank you for the offer. It seems like they are different from the TR ones. So, I won't be able to use the 512TR one, unfortunately
     
  10. Jbar2002

    Jbar2002 Karting
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    Mar 3, 2021
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    John Barhydt
    #10 Jbar2002, Apr 21, 2024
    If you have the original cats and pipes for the 512tr I’m interested in them.


    Sent from my iPad using FerrariChat
     
  11. bernieb

    bernieb Karting

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    #11 bernieb, Apr 22, 2024
    I've sent you a pm.
     
  12. 2dinos

    2dinos F1 Rookie

    Jan 13, 2007
    3,072
    #12 2dinos, May 4, 2024
    Do they have to be stock cats? HJS makes all sorts of cats.
     
  13. alex_kay

    alex_kay Karting

    Apr 7, 2024
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    #13 alex_kay, May 10, 2024
    To give everybody an update here, too :)
    In the meantime I was able to source two catalytic converters. Thank you @bernieb.

    And for others to make the search easier:
    On 87 TRs the Ferrari parts number is 121385 (121 385). It also says Zeuna Augsburg ZS428 (or ZS 428).
    It seems they are identical with the ones on the 512TR. They carry the Ferrari parts number 8149304 (or 8149 304). It also says Zeuna Augsburg 223669901 (or 223 6699 01 or 223 6699 J 01 or 2236699J01).

    I hope that it might help someone someday :)
     
  14. Rifledriver

    Rifledriver Three Time F1 World Champ

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    #14 Rifledriver, May 10, 2024
    149304 fits 512 TR and M only.
    121385 does not fit 512. It fits 308QV 328, and TR up to 91 as well as Mondial 3.2
     
  15. alex_kay

    alex_kay Karting

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    #15 alex_kay, May 10, 2024
    @Rifledriver are you sure the 512TR ones don't fit on the Testarossa? I could swear they look identical and have the same mountings.

    @bernieb Can you bring light into the dark? Were the two ones both mounted on your Testarossa?
     
  16. Rifledriver

    Rifledriver Three Time F1 World Champ

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    #16 Rifledriver, May 10, 2024
    I just make this **** up to confuse people.
     
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  17. alex_kay

    alex_kay Karting

    Apr 7, 2024
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    #17 alex_kay, May 10, 2024
    OK, let me rephrase: What is the difference between the cat on the Testarossa and the 512TR?
    And: Can you drive the 512TR cat on the TR? And potentially vice versa?
     
  18. alex_kay

    alex_kay Karting

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    #18 alex_kay, May 10, 2024
  19. BR in the UK

    BR in the UK Rookie

    Sep 18, 2006
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    #19 BR in the UK, Jun 8, 2024
    Do you still have those 512tr cats?
     
  20. bernieb

    bernieb Karting

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    #20 bernieb, Jun 9, 2024
    The cats I shipped are what came back from Newman when I upgraded my testarossas' exhaust. Two possibilities...they either came off the car, or Paul had another cat in his shop and inadvertently sent me a 512TR cat back with the car. Entirely water under the bridge to me. I'm now running a Fuchs system with neither cats nor pre-cats and after 8 years or so I'm very happy with it. Pretty sure the 512M crate motor he dropped in way back then helps with the audio track too!
     
  21. Rifledriver

    Rifledriver Three Time F1 World Champ

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    #21 Rifledriver, Jun 9, 2024
    They are different lengths. You cannot adjust for a different length.
     
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  22. BR in the UK

    BR in the UK Rookie

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    #22 BR in the UK, Oct 13, 2025 at 12:13 PM
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  23. turbo-joe

    turbo-joe F1 Veteran

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    #23 turbo-joe, Oct 13, 2025 at 1:22 PM
    but made in germany ( augsburg in bavaria ) by ZEUNA ;)
     
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  24. Auraraptor

    Auraraptor F1 World Champ
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    #24 Auraraptor, Oct 14, 2025 at 2:12 PM
    I should check as I am pretty sure I have both 512TR and testarossa cats in my parts collection. From memory, they look nearly identical. If there is a length or mount difference its very subtle / not easily seen by eye. I think the only meaningful difference was the extra o2 sensor hole (again from memory)
     
  25. Steve Magnusson

    Steve Magnusson Two Time F1 World Champ
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    #25 Steve Magnusson, Oct 14, 2025 at 3:45 PM
    That "extra" port on the TR cat (121385) is not for an O2 sensor -- it's an inspection port to be able to visually examine the catalyst honeycomb (and is a different thread size) and/or be a place to sample exhaust gas upstream of the catalytic element. Seems they decided that it was just not needed on the later 512TR cat (as one can just remove the O2 sensor and do the same thing).
     
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