454 enigne. Which headers?

[BlitzK5]

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

 

[shane74]

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

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.

 

[BlitzK5]

K thanks

 

[blazinzuk]

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

 

[BlitzK5]

K thanks

 

[Mad-Dog]

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....

 

[85454blazer]

Flowtech headers fit on my 85 with a 454 no clearance issues

 

[Sandman]

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

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.

 

[hero]

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.

 

[Z3PR]

Thorley Tri-Y's are pretty damn good from what I hear.

 

[HarryH3]

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.

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...

 

[hero]

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...

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?