Longtube Headers With Catts?

Discussion in '2005 - 2014 S-197 Mustang -General/Talk-' started by MyJayy, Feb 10, 2013.

  1. So I've heard and seen people put Long tube headers on there 05-09 mustang gt with catts!?
    Is that a lot of custom work? Does it knock down the power you get out of the Long tube headers if you add catts? Will it pass smog with legal catts? If so what kind of catts are they?
  2. No custom work at all, when you buy a premium set of long tubes such as American Racing Headers you get a complete ssystem with headers and mid pipe, It's a straight forward install although time consuming. With a good tune you can pick up 25-30 rwhp across pretty much the entire rpm range on a 3v and 30-40 on a Coyote. That's with cat's
  3. Dam that sounds like some good power gains, American racing headers is really pricey though. Is that what you have ?
  4. Thank you earley's !! for the links too. That's what I was trying to look for!!!
  5. No problem
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  6. Yes I have them on my personal car, and yes they are expensive but they are THE best. LT's are something you wan to buy once and install once. I've had mine on for 3 years and still look brand new. They are expensive because they use the best materials, all sourced in the USA and are hand crafted not pumped out by a machine like the cheapo Chinese ones.
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  7. The car will not pass emissions with L/T's and catted mid pipe in CA. Everything in CA requires a CARB number and there aren't any L/T headers with a CARB number, that I am aware of.

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  8. Notwithstanding the "California" problem -
    Also be aware that not all hi-flo cats are created equal. If the rear O2's are turned on in your tune, then you may get cat efficiency codes. With these you cannot pass the OBD2 part of inspection. If the rear O2's are off in your tune, you also will not pass OBD2 inspection.
    Some have had luck with rear O2's turned on in the tune and using anti-foulers (single or doubled). This would not work for me - I had to get green cats from Kooks Headers. Worked like a charm.
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  9. I am running jba set up " Cartted " and comp cams ,though my tuner and comp said run cat less,I just got back from a 1100 mile trip in mine and really glad I'm running cats !
  10. I ran with BBK longtubes and cat'd shorty x-pipe. Had the 02 efficiency problem but only on one side. BBK didn't help me at all saying it's a hit or miss and have a good day. I'll end up replacing the cats eventually but right now I'm ok because I'm in a safety only inspection area.
  11. Sometimes I have a cat efficiency problem too on driver side. Usually if I let the car get to operating temperature before I drive off it doesn't happen.