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True duals...anyone else have this problem?

Discussion in 'The Garage' started by potionmaker, Jan 30, 2006.

  1. potionmaker

    potionmaker 1/2 ton status

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    So...Im in the middle of my engine swap and wanted to go with headers and run true duals all the way back. However, all of the exhaust shops say that they cannot replace the current exhaust (single) with duals all the way back.:rolleyes: Is this just a Virginia thing or EVERYWHERE??? They tell me I have to put a "Y" from the headers, run through 1 cat and 1 muffler, and split after that. This sounds absolutely ridiculous, especially since Im willing to put a cat and muffler on both sides for true duals.

    Second, does it make sense to still use headers if I have to return to a single pipe for muffler and cat? What would / did y'all do?:confused:

    Thanks for your opinions and insight. This blew me away when I heard this, but then again, I dont know a great deal about these ins and outs.:D
     
  2. boz42

    boz42 1/2 ton status GMOTM Winner

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    never heard that before. if that is the only option u have i would run headers a large y, buy one from jegs, summit etc. then run 3"'''' to high flow cat & 3" to muffler of your choice. single 3" will flow enough for all but the wildest small blocks (i don't believe this is a popular believe though)
     
  3. sandawgk5

    sandawgk5 3/4 ton status

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    Yep it is a federal law that all emissions have to remain as built. Your cat is a part of the emissions system. Therefore if it has 1 cat it has to stay 1 cat. If 2 it stays 2 if 4 well you get the idea.:rolleyes: On top of that the cats are required to be in the factory location to ensure they reach the appropriate temperature to ensure they perform as designed. Does everyone follow these laws? No. I am sure there is some shop that will do it. Find a mom and pop place. If they are caught though it is big fines from Big Brother. I also believe that a single 3" will flow just as much as dual 2.5s. I will be going 3" on mine plus it is less **** to get hung up offroad.:D

    Ira
     
  4. sledheadak

    sledheadak 1/2 ton status GMOTM Winner

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    federal law prevents them from removing a converter.some shops will run a true dual system if the converter is not present.or makes freinds with a muffer guy and have him do it after hours.
     
  5. K5er4Life

    K5er4Life 1/2 ton status

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    Here in cali we cant convert single to dual, even if we put cats on both sides. I dont know how your state is with smog but they may have a similar law, however if you want it that badly tell them its for "offroad" use only, although my shop knew that was bull they just didnt want to give me a reciept which is fine by me. Look into your smog laws before you do it and if its legal to do then tell the shop that its not a street driven vehicle. However, I have made friends with the guy that does exhaust so he doesnt have a problem with me.
     
  6. K5er4Life

    K5er4Life 1/2 ton status

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    Dude, your avatar is annoying!
     
  7. sandawgk5

    sandawgk5 3/4 ton status

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    Here ya go if you want to know what the law actually states here it is. It also has some other good info in the article.

    Ira
     
  8. potionmaker

    potionmaker 1/2 ton status

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    Thanks for all the tips. 3" it is!!!!!!
     
  9. YELL78

    YELL78 Registered Member

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    I run a 2 1/2 y pipe into 3'' out the back
    power is great probably better low end that duals.
     
  10. potionmaker

    potionmaker 1/2 ton status

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    Would you stay with a single the rest of the way out or split after the muffler? The way I see it, why pay the extra money just for the looks, unless the extra "out" helps.

    Also, what muffler would y'all recommend? I would like a low "growl" but not too loud.
     
  11. sandawgk5

    sandawgk5 3/4 ton status

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    I plan on a high flow 3" cat and a 3" super 40 Flowmaster.

    Ira
     
  12. boz42

    boz42 1/2 ton status GMOTM Winner

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    i would run single all the way out, i think it sounds better. if u want low growl, flowmaster makes a huge single in/out it is a 3" muffler i'll find a part # for ya
     
  13. Chevy305

    Chevy305 6 Lug 14bsf Status Premium Member GMOTM Winner

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    I am running true duels, no cats, no egr, no air pump, and a holley carb. Yeah and my truck is technichally a 74 K10 but with the vast majority of the parts on it from 85. Like the chassi and front clip, interior. I like how the Massachusetts law saws that for all cars produced in 1983 or older are emissions exempt. So I take advantage in saying that my truck is a 74 when its really not. When I had it inspected last, the only problem the guy had was that he wasn't sure if it was too high off the ground. But it is with in the law.

    So there are ways to get around emissions.
     
  14. YELL78

    YELL78 Registered Member

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    i run my single 3" out behind the driver side rear tire i run a flowmaster copy that i got from jegs its not horribly loud but its up there in the db levels but the truck sounds awsome every time i start is it turns heads one time i picked up my girlfriend for lunch at her work and there was all kinds of people outside when i pulled up the were all looking at me and when she came home that night she said like 10 people mostly women told her tho let me know that my sounded better than anything they had ever herd so i would say just stay with the single.
     
  15. potionmaker

    potionmaker 1/2 ton status

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    Thanks everyone!! Anymore opinions on brands of mufflers? I think I'm gonna have to go with the single, but it sounds as if it's not as bad as I thought it would be. The idea of true duals just sounded cool:D Think Im gonna go with headers to a 2.5" single, new cat and still undecided on the muffler. I will dump it out behind the rear driver's side tire like the stock configuration.
     
  16. kram

    kram Registered Member

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    tax time

    ordering edelbrock tes mid length,y pipe w/a.i.r ports.
    got a 3-4-3" high flow cat from thunderbolt.
    already have duramax 3" cat back.
    inspection is in feb. so i will wait till then.
     
  17. muddybuddy

    muddybuddy 3/4 ton status

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    potionmaker, where in VA are you?

    man i was going to order some long tubes and do true duals, now im starting to wonder if i i should still do it. i need t do something cuz the driveshaft hits the y-pipe
     
  18. JohnDeere

    JohnDeere 1/2 ton status

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    You can do true duals and still get away with emisions they say that if it comes from factory with duals then it must stay and same for single but i got a 85k5 that came factory with single and have dual glaspacks and passed emesions easly. U can buy a dual set-up for a old k5 and run it on an 83 and new and it should fit thats what i did i order dual from lmc for the older blazers and it fit fine. dual glaspacks sound great with out converters and there realy loud with a good growl, when i put my converters on it got quiet and gave it an ok growl.
     
  19. potionmaker

    potionmaker 1/2 ton status

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    Hey Muddy....Im in Chesterfield, just outside of Richmond.

    I think Im gonna stick with the single. Im not worried about it passing inspection. I have a few friends in low places:D. I have already taken all of the power-eating smog crap off. I just cant find a muffler shop that will run duals. I guess if it were my muffler business, I wouldnt jeopardize it either just so some wanna-be redneck (me:D ) could have dual exhaust.

    Just trying to decide on the muffler now!!
     
  20. Chaddy

    Chaddy 1/2 ton status GMOTM Winner

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    Thai is what I did and I think it's great! Less hang up's, no $ for more pipe and second cat, and it sounds real nice.
     

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