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Doug Thorley Tri-Y headers

Discussion in 'Engine & Performance' started by Green79Scottsdale, Apr 5, 2020.

  1. Green79Scottsdale

    Green79Scottsdale Full Access Member

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    Truck Year:
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    K20
    Engine Size:
    400
    I have been keeping an eye open for headers for a while now. Just stumbled upon a set of Thorley's for a reasonable price. Does anybody have pictures of some installed? Specifically on a 4wd would be nice. I can't say I have ever heard anything negative about them. Any other review on them would be nice too. Fitment? Spark plug access? Thanks in advance. I had @hirschdalechevy in mind specifically on this.


    edit: Added picture from for sale post. $200

    DT-TY.jpg
     
  2. Turbo4whl

    Turbo4whl Full Access Member

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    My pictures would not help you as I have a set of Tri-y's on my big block low rider. I can tell you I have been very happy with their fitment and performance. Thorley states the chrome plating is not for show, but rust protection. That feature works well too, as mine are very old and still fine.
     
  3. xylorex

    xylorex Junior Member

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    383 -Forged Scat rotating assembley, Edelbrock ProFlo EFI, Roller lifter/rockers, CompCams XFI268
    I spent the money on a set of these for my 87 1/2 ton 4x4 (v10). I sent them back because they hit the frame on the passenger side. Product looked great quality, just didn't want to cut on my frame that much.
     
  4. 78C10BigTen

    78C10BigTen Full Access Member

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    Id like to see said lowrider :naughty:
     
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  5. Turbo4whl

    Turbo4whl Full Access Member

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    Well here is a picture of said headers. I don't want to side track this thread. I'm thinking about selling it, but right now sure isn't a good time.

    IMG_3350.jpg
     
  6. 78C10BigTen

    78C10BigTen Full Access Member

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    Squarebody?
     
  7. Green79Scottsdale

    Green79Scottsdale Full Access Member

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    You wouldn't be side tracking this thread at all! Post up some pics! Big block, small block, lowrider, 4x4... I don't care.
     
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  8. Turbo4whl

    Turbo4whl Full Access Member

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    Okay. @78C10BigTen take note.

    IMG_3340.jpg IMG_3339.jpg IMG_3346.jpg IMG_3349.jpg
     
  9. 78C10BigTen

    78C10BigTen Full Access Member

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    DoubleDingo and Turbo4whl like this.
  10. Turbo4whl

    Turbo4whl Full Access Member

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    Okay, a couple more. I took delivery of the '82 in November of 1981. During the following summer I installed a Shelby/Spearco turbo kit on the original small block.

    '82 turbo1.jpg '82 turbo2.jpg
     
  11. ajd89

    ajd89 Full Access Member

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    Heres mine came with the truck. Technically they are installed lol.

    20200408_154552.jpg
     
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  12. Kevin S

    Kevin S Junior Member

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    Truck Year:
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    Truck Model:
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    BBC 454, manual SM465
    I recently put a set on my '79 2wd manual 454 BBC build. Fit real nice. No discoloration and run surprisingly cool with the ceramic coating. Quite thick and I feel top-quality, happy with the choice.

    THY-303Y- 4:2:1 long-tube headers, primary tube 1-3/4", 14ga, 2.5”, 3/8 flange, ceramic coated, $705 from http://www.dougthorleyheaders.com/1...p--suburban--blazer-(2wd)-tri-y-headers_15855

    IMG_7401.jpeg
    That tube on the end is for a choke heat riser.
    IMG_7404.jpeg
    Collector ends near the SM465 tailhousing taper. My complete exhaust system (side exit dual stainless, longest/largest oval 2.5" Flowmaster) does not hang below frame, tucks up real nice.
    IMG_7406.jpeg

    exhaust (1).jpeg

    exhaust (2).jpeg
     
    Last edited: Apr 9, 2020
  13. highdesertrange

    highdesertrange Full Access Member

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    IMO there is something funny about that set in the first post. the passenger side one doesn't look right for a squarebody. highdesertranger
     
  14. Big Chip

    Big Chip Full Access Member

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    Do you have an exhaust gas temperature gauge in that thing?
     
  15. DoubleDingo

    DoubleDingo Summer Is Near, Hot Temps Are Already Here

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    Carb'ed Vortec 350; 1972 L48 350
    Those would make me consider headers. Nice product.
     

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