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Subject: Finally passed CA smog check Author: cheung1 as Patrick C 88 750 160K New piston rings : member since March, 2004 : 1152 posts Posted on: 2007-11-15 16:23:52

The aftermarket pair of cat that I put on a few years ago were now down to 46% and 22% efficiency, apparently due to the burnt oil coating over the elements. New, but still aftermarket cats are now welded on and car passed smog check.

The repair people told me the bolt-on OE cats($1200 their price) can last 5-6 years but my aftermarket units will last much shorter. Other than these two options, there are BMW-made cats that cost $3000 a pair. I suppose the OE type are the bolt-on ones we can find online for $800'ish a pair that comes with pipes and connections; and I am not sure why they come with more catalytic elements. However, I can believe the BMW-made ones contain 10 times the catalytic elements because (I was told) the shops that buy back used cats are willing to pay $100 for the BMW cats, but just $10 for aftermarket cats to reclaim the precious metal inside.

The CA state picked up $500 of my bill and I paid $300; not bad considering that I would have paid more to purchase Magnaflow cats ($212 for a pair) and in addition would have to pay a welding shop to install the units on my existing pipes.





Patrick C 88 750 159K

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  • Finally passed CA smog check (pic) - Patrick C 88 750 160K New piston rings 2007-11-15 16:23:52 (542 views)
    • Really impressed with your re-ring spread. Thanks - beezer02 2007-11-17 23:37:38 (92 views)
    • Great Day!!, Congrats Pat!!!! (url) - shogun 2007-11-15 21:52:11 (140 views)
      • Glad to see you're back on the road, Pat. - Rich 1990 750iL 2007-11-15 22:52:01 (107 views)
      • Congratulations Patrick! - bcweir750 2007-11-15 21:57:51 (97 views)
        • Thanks. Yes, feel good giving back to the Internet - Patrick C 88 750 160K New piston rings 2007-11-16 18:25:19 (109 views)