What % of you do/don't have catalytic converters? and drone follow up...

Discussion in '1994 - 1995 Specific Tech' started by Pokageek, Oct 5, 2006.


?

Please pick your set up..I have:

  1. oem (4) cat h-pipe

    14 vote(s)
    9.3%
  2. 2 cat h-pipe

    18 vote(s)
    12.0%
  3. 2 cat x-pipe

    19 vote(s)
    12.7%
  4. NO CAT h-pipe

    57 vote(s)
    38.0%
  5. NO CAT x-pipe

    30 vote(s)
    20.0%
  6. Other

    12 vote(s)
    8.0%
  1. final5-0

    final5-0 Mustang Master

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    From everything I've seen about high flow cats ............

    You would only pick up two or three rwhp if you went off road.

    You see peeps talk about a noticable gain by going to OR pipe.

    Of course they do :nice: .............

    That oem 4 cat pipe is really restrictive ..........
    even all the more so if a lotta miles has been put on it.

    Grady
    #21
  2. Cwalk

    Cwalk New Member

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    No Cat BBK X-pipe, flowtech shorties, and flowmaster's.
    #22
  3. MI95Cobra

    MI95Cobra New Member

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    custom built offroad x-pipe, no cats, flowmasters pro-dumped looking for headers....
    #23
  4. 95strokerPSU

    95strokerPSU Member

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    Custom H-pipe with hallowed out cats and flowmaster cat-back. Drones at 2k but my cruising RPM is 2500-3000 on the street with the 4.10 gears. I don't do any highway driving.
    #24
  5. Pokageek

    Pokageek Active Member

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    I was thinking of actually trying this...but will that mean unequal backpressure? Mess up the engine? I am not sure I want to pay $100 for another flowmaster to find out. Anyone want to try it?

    Oh, yeah and some of ypou posted but did not say whether your combo drones.:shrug:
    #25
  6. igotyofire

    igotyofire Member

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    i think ur basing drone off the mid pipe rather then the mufflers which is where i think it should be. chambered mufflers seem to be more prone to droning then say straight thru muffler designs. Anyone else agree? my upr x pipe and magnaflow design i guess i would say has a bit of drone but i just consider it much louder then the stock mid pipe and not so much drone, atleast not so much in my opinion..ive heard worse with dumped exhaust,heh
    #26
  7. diablostang

    diablostang New Member

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    Pay attention to the MUFFLERS... That's what creates the drone. I've had maybe 5 5.0 Mustangs with Flowmasters, and have also had Mac, Dynomax and Flowtech mufflers.. and they all droned and gave me a headache. I'm currently running NO mufflers, and there's no drone and no headache. Mufflers like the Mac / Flowmaster / Dynomax / Replicas will all drone.
    #27
  8. Pokageek

    Pokageek Active Member

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    Hmm... No mufflers. No drone. That's interesting. But won't it be LLLLLLLLLLLLLOOOOOOOOOOOOOOOOUDDDDDDDDDDDDDDDDDDDDDDDDDDDDDD!!!!!!! As hell? (illegal round here.) :)

    Maybe I should try thrush glass packs?
    #28
  9. HISSIN50

    HISSIN50 "How long does it take to get help in here? SN Certified Technician

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    Seems to me that you're spot-on here. :nice:

    Seems to me that drone is related to resonance. If someone wants to phase shift the drone-zone, it seems to me that a resonant chamber (a dead-head in the exhaust) could help. It would not be completely unlike the stock set-up.
    #29
  10. Pokageek

    Pokageek Active Member

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    Thanks Hissin. But what does this mean in every day terms?
    #30
  11. BlackVert

    BlackVert Mustang Master

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    EL shorties, stock cats, flowmaster 40 cat back

    drones cruising 2000-2230 or so
    #31
  12. Pokageek

    Pokageek Active Member

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    BVert, when are you going to get some longtubes for that car! :)
    #32
  13. Therian

    Therian The Highlander Founding Member

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    Longtubes + mac hi flow catted H (4 cats) + flowmasters

    =

    no drone.

    very nice tone...very deep

    personally I'd like to go to a more exotic note. but that can wait
    #33
  14. HISSIN50

    HISSIN50 "How long does it take to get help in here? SN Certified Technician

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    The engineering folks who enjoy fluid dynamics can probably help more than I can. But from what I understand, the exhaust pipe itself has a certain resonance frequency (like a tuning fork). If you shorten or lengthen the pipe, that in and of itself can change the frequency at which the pipe vibrates/drones (you would phase-shift the RPM at which drone occurs. E.g. if you shortened the exhaust pipe X inches, the drone RPM might move from 2000 to 2600 RPM, and if you dont cruise at 2600 RPM, who cares).

    The other way to treat it is to create resonance chamber (this is used for wave cancellation - it's common in plumbing, electronics and so on). Now I think you are actually cancelling the waves (all that node/anti-node stuff). This is where that deadhead pipe comes into play, and would likely be what I might try - I know the drone drives you nuts.

    Maybe the engineers can pipe (pun intended) in here and offer assistance....... I've done a bit of exhaust work like this but it was all just me crunching crude numbers and experimenting. It'd be nice if someone knew how to actually predict something.......
    #34
  15. Pokageek

    Pokageek Active Member

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    Yes but 4 cats = reduced HP.
    #35
  16. mustang6tee8

    mustang6tee8 Member

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    stock headers, MAC o/r H, JBA catback, (built very well, gorgeous 3" tips, I have the prototype model cause I am very good friends with the son of the owner of JBA!! I've met the owner too, he's a great guy...mostly cause he's an Aggie:D ) still drones from 1950-2050 rpm, but i've heard that it's because of the head design
    #36
  17. The Green GT

    The Green GT No 13 year olds are safe around me.

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    No muffs or cats w/ turndowns here.

    Drones so much I want to put a bullet through my head sometimes.
    #37
  18. Al J

    Al J Member

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    Motorsports equal length shorty headers, Bassani X p[pe w/CATS, Borla cat-back--still has the 1800-2100 drone.
    They all do---except maybe the long tube headers.
    I've got a set of stock 2003 catbacks that I'm seriously thinking about installing.
    #38
  19. Stanger007

    Stanger007 Founding Member

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    Mac Longtubes, prochamber and catback - slight drone at 2k that I *LOVE*. :)
    #39
  20. Pokageek

    Pokageek Active Member

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    How about the lon-tube guys...less drone?
    #40

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