Dismiss Notice

Welcome To CK5!

Registering is free and easy! Hope to see you on the forums soon.

Score a FREE t-shirt and membership sticker when you sign up for a Premium Membership and choose the recurring plan.

454 enigne. Which headers?

Discussion in 'The Garage' started by BlitzK5, Jul 30, 2005.

  1. BlitzK5

    BlitzK5 1/2 ton status

    Joined:
    Jul 29, 2005
    Posts:
    288
    Likes Received:
    0
    Location:
    Sherwood Park, Alberta, Canada
    Whats a good set of headers to put on my 82 k5 blazer with a 454?. Im worried about clearance problems. Also which ones will give the most power/hp increase? Does anyone have the same enigne with headers that could offer some advice?
    Thanks

    454/TH350/NP208/4" lift/10 bolt F/14 bolt FF/38X15.5X16.5
     
  2. shane74

    shane74 1/2 ton status

    Joined:
    Feb 12, 2002
    Posts:
    4,100
    Likes Received:
    0
    Location:
    Vancouver, WA
    The only thing I know for sure is that the long tube headers give you more low end torque than the shorty block huggers. What brand do you want to run? Sometimes, the best way to find out what you need is to figure out which brand you want to run and then call them directly.
     
  3. BlitzK5

    BlitzK5 1/2 ton status

    Joined:
    Jul 29, 2005
    Posts:
    288
    Likes Received:
    0
    Location:
    Sherwood Park, Alberta, Canada
    K thanks
     
  4. blazinzuk

    blazinzuk Buzzbox voodoo Premium Member GMOTM Winner

    Joined:
    Dec 20, 2002
    Posts:
    17,412
    Likes Received:
    3,799
    Location:
    Afton / Star Valley Wyoming
    I have a freind that is running big block chevelle headers on his K5 tons of ground clearance. Just find Sandman on this board and pm him
     
  5. BlitzK5

    BlitzK5 1/2 ton status

    Joined:
    Jul 29, 2005
    Posts:
    288
    Likes Received:
    0
    Location:
    Sherwood Park, Alberta, Canada
    K thanks
     
  6. Mad-Dog

    Mad-Dog 1/2 ton status

    Joined:
    Mar 20, 2005
    Posts:
    548
    Likes Received:
    0
    Location:
    Ocklawaha,Fl
    1 3/4 primary pipes will do for a stock/mild rat motor, full-length headers are not an option as shorty headers are simply tubular replacements for a stock manifold.
    Run 3" collectors at least 20" long and then reduce to 2.5" all the way back to "free-flow" mufflers then out each side behind the back tires at a 45 degree angle.
    A balance pipe, x-pipe or crossover (whatever u wanna call it) may or may not increase torque at low rpm's but it will definately smooth out the exhaust note and help to tame the loud mufflers, at any rate it should be installed after the colllectors....
    A properly designed, built and tuned exhaust system can add as much as 85 HP to a motor by scavenging the spent gases from the chamber and pulling a fresh air/fuel mixture into the chamber, the piston on it's intake stroke plays a some-what smaller role than the exhaust scavenging does when it comes to drawing a fresh mixture into the chamber.
    headers by themselves are a important part of the total exhaust system and the system as a whole can make a great engine or a so-so engine.... :bow:
     
  7. 85454blazer

    85454blazer Registered Member

    Joined:
    Apr 24, 2005
    Posts:
    5
    Likes Received:
    0
    Location:
    NY
    Flowtech headers fit on my 85 with a 454 no clearance issues
     
  8. Sandman

    Sandman 3/4 ton status Author

    Joined:
    Apr 15, 2002
    Posts:
    5,653
    Likes Received:
    0
    Location:
    Pocatello, ID
    The Chevelle headers are great! You have to grind the motor mount a little on the drivers side and do a slight amount of frame clearencing (sp?) on the passenger side. They are very high and clear the shackel and the driveline very easily. My passenger exaust actually runs over the top of the transfercase.
     
  9. hero

    hero Registered Member

    Joined:
    Oct 21, 2002
    Posts:
    65
    Likes Received:
    0
    Location:
    Omaha, NE
    It looks to me that Hooker makes a header exactly for it. Summit Racing has it listed as pn hok-2463hkr. That's what I was going to get for my '83 with a 454. I haven't ordered them yet, so I don't know for sure how well they fit.
     
  10. Z3PR

    Z3PR Banned

    Joined:
    Mar 30, 2002
    Posts:
    19,217
    Likes Received:
    0
    Location:
    Everywhere
    Thorley Tri-Y's are pretty damn good from what I hear.
     
  11. HarryH3

    HarryH3 1 ton status Author

    Joined:
    May 31, 2000
    Posts:
    10,384
    Likes Received:
    2
    Location:
    Georgetown, TX
    Click on the "Application" tab and read the fine print. Those are made for 2WD models. That typically means that they won't clear the springs/shackles on a 4WD. :( I wouldn't contact the tech folks at Hooker before laying down your cash...
     
  12. hero

    hero Registered Member

    Joined:
    Oct 21, 2002
    Posts:
    65
    Likes Received:
    0
    Location:
    Omaha, NE
    Yeah I saw that too, but if you go to Holley.com (http://www.holley.com/types.asp?type=430) and you look at products, etc and you find the part number for those headers it reads a little different. This is what is on the web page."Competition Header, 69–91 Blazer/Jimmy/Yukon/Tahoe 2DR. (4WD), 69–87 1/2, 3/4 & 1 Ton Truck (4WD): 396–502, Tube Size 1.75" O.D. x 31", Collector Size 3" O.D., Collector Length 8", Port Shape: Same As Port, Ceramic Metallic Coating "

    So based on that, I would think it should be fine. I should know in about a week. Although I'm a little confused since it says Ceramic Metallic Coating, and Summit says painted. Maybe they used a ceramic based paint???

    For the guy that said he used BB Chevelle headers, what year? I'm guessing 68-72?
     

Share This Page