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I switched my exhaust and now I have power and torque where I shouldn't

Discussion in 'Engine Building' started by Sparta_7, Apr 18, 2007.

  1. Sparta_7

    Sparta_7 New Member

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    Hey guys, I'm in a bit of a confused state. Ok, here's my situation.

    I have a 94 prelude, with the H23a1 (non-vtec) engine. I had modified it with the basics, intake, headers, stock cat (i bought and still have a hi-flow, but I had to put the stock cat back on, explained later), and 2.5" cat-back exhaust , straght-through, no muffler a four-inch tip on the back ( a pair of two-inch diameter pipes, I thought I could be letting the gas get to cool by allow to expand and putting more strain on my engine pushing that ar through by doing so, but it looked good).

    Alright, now, as expected, I lost some low-end torque, and gained some high-end power, and all was fine and good in the world. I put on the high flow cat, but then there was NO obstruction to the gas and that thing was LOUD. and I mean LOUD. So I put the stock cat back on. But the exhaust was still pretty loud. so after about three months (and a moving violation ticket for the exhaust noise) I decided to get a muffler or a resonator put on. Which I did two days ago.

    I put on a good-looking 2.5 inch muffler, the type with the perforated holes on the inside, it killed the noise but it also did something unexpected. It gave me a LOT more power, low-end torque AND high-end grunt. Enough for me and every passenger I've jammed the throttle with to notice. I would expect to get some torque back, but I'd expect g's to fade once I pass 4000 rpm, what the hell happened?

    and P.S,
    friends have been telling me all the backpressure I'm trying to get rid of will hurt my exhaust valves, because they'll get less cushioning when coming back from their excursion into the cylinder, how true is this and to what degree?
    As well, the muffler I have has a silencer that bottlenecks the flow to one inch, that's way too much, I know, and I notice the significant performance differences between the two exhaust flows (especially since my engine will bog under 1500 rpm). My question is, what will too much backpressure do to an engine?

    All ight, that's it^_^
     
  2. TurboMirage

    TurboMirage YEEAAAHHH VIP

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    2.5in catback seems a little much. i would have run 2.25
     
  3. Sparta_7

    Sparta_7 New Member

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    okay

    alright, i agree with that, but my other question still stands. If i was to put on my hi-flow, do i risk damage to my valves? how much backpressure is enough backpressure, and what does too much do?
     
  4. formby

    formby learning in progress

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    how will HI FLOW....never mind

    i think you had another post on this...


    youll be okay like stated on your other thread
     
  5. MoSeS

    MoSeS New Member

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    this is kinda frustrating and funny at the same time. you want to have the least amount of backpressure with the most velocity. you need to find that happy median between piping so big that you lose velocity and piping so small that you have too much backpressure. sounds to me like you found it. i would try the high flow on there and see how it feels, if it feels more powerful leave it on, if it feels like its bogging down some take it off. itll prob be better with it on.
     
  6. Sparta_7

    Sparta_7 New Member

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    Cool, thank you guys.
     
  7. D16SiHatch

    D16SiHatch New Member

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  8. Briansol

    Briansol Admins Admin VIP

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    holy crap. you came back 2 years later to say thanks? lol
     
  9. D16SiHatch

    D16SiHatch New Member

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    lmao, i didn't even catch that
     
  10. phunky.buddha

    phunky.buddha Admin with a big stick Admin VIP

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  11. BrutalB83

    BrutalB83 Brutal Moderator Moderator VIP

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    :lmao: That's fucking hilarious. He may not be punctual, but he is polite...
     
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