Headers for economy on 82 K10?

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t44e6

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My K10 runs great but was thinking of maybe putting headers on it and a lower restriction muffler if economy might be boosted a bit. It has a rebuilt smog era 350 in it with I believe the much reviled lightweight "624" heads and a QJet on a stock intake. Is it reasonable to expect any boost in economy? Will I need to re jet or do extensive tinkering with the carb? My only experience with headers has been in vehicles built to burn as much fuel as possible.
 

Frankenchevy

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I doubt you’ll notice anything. I feel like headers on anything under 400 hp are for looks, sound and butt dyno.

A decent set of powder coated headers with a thick flange are $700ish. Most headers other than some shorties will require your exhaust to be reworked(more $$$). Depending on miles driven, may take some time to recoup at 0.1 mpg increase.
 

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It all depends on how heavy your right foot is. The headers sound may increase its weight. Carb adjustments MAY be necessary, but doubtful. Use a vacuum gauge.
 

75gmck25

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Based on what I've seen from various Engine Masters videos, headers and low restriction exhaust will increase low end torque and and keep giving more HP through the entire RPM range. That extra torque might allow you to use less throttle, and therefore save a little on gas use, but its not really a tool to improved MPG.

Does your truck already have dual exhaust? The reason I ask is that with most of these trucks the crossmember doesn't provide good exhaust clearance on both sides. The driver's side (original single exhaust location ) has lots of space, but the crossmember gets in the way on the other side. However, you might be lucky and have the W-shaped crossmember that provides space on both sides.
 

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You'll likely get more economy from transitioning to driving like a complete grandpa..

Suuuuuper slow acceleration, minimum rpm shift pattern. Pretend there's an egg between your foot and the gas pedal, an egg you don't want to break.

I started doing this with my daily driver a couple weeks ago and it's given me +3 mpg.

Tire choice can make a rather large difference as well, on some vehicles anyways. With my daily driver, the difference between a 33" c rated tire and a 33" e rated tire is 4-5 mpg.
 

t44e6

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I doubt you’ll notice anything. I feel like headers on anything under 400 hp are for looks, sound and butt dyno.

A decent set of powder coated headers with a thick flange are $700ish. Most headers other than some shorties will require your exhaust to be reworked(more $$$). Depending on miles driven, may take some time to recoup at 0.1 mpg increase.
Good points. Any real improvement would require a dedicated build. I don't think a bolt on EFI would make any real difference either. Carburetors are really a type of mechanical computer and whoever set up the Q-jet on this one did pretty good. If I ever did get any I would probably get Sanderson shorties, but at most I may just put a aftermarket set of cast iron units on.
 

shiftpro

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True dual exhaust over a two into one will gain a little on a stock engine.
 

fast 99

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How much do you drive it and how much will it cost? Figuring that out you may never see a monetary gain. Doubt any kind of a huge increase 1 or 2 mpg............maybe. Headers cause other issues as well, may need heat resistant plug wires, additional exhaust work, bracket changes, extra heat on the starter, and then the dreaded header leaks down the road.

However, if you want headers because of the way they sound by all means do it. Life is short.
 
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Snoots

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I went over my header flanges with a belt sander, 80 grit, and used 2 gaskets. Never a leak.
I also used Eastwood's High-Temp Ceramic Coating inside and out. Very nize!
 

fast 99

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I went over my header flanges with a belt sander, 80 grit, and used 2 gaskets. Never a leak.
I also used Eastwood's High-Temp Ceramic Coating inside and out. Very nize!
Have one vehicle with headers. They were very expensive with thick flanges and coated. The flange bolts get checked every season, no leaks. However, I have seen many that do. Not sure if they were a lesser quality header or just not checking the bolts occasionally. Once the gasket starts to burn its tick tick tick from then on.
 

t44e6

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You'll likely get more economy from transitioning to driving like a complete grandpa..

Suuuuuper slow acceleration, minimum rpm shift pattern. Pretend there's an egg between your foot and the gas pedal, an egg you don't want to break.

I started doing this with my daily driver a couple weeks ago and it's given me +3 mpg.

Tire choice can make a rather large difference as well, on some vehicles anyways. With my daily driver, the difference between a 33" c rated tire and a 33" e rated tire is 4-5 mpg.
I have probably a million miles driving carbureted trucks of various sizes with manual trannys, from a 1961 Ford C-600 to 1980s GMCs with the last of the carbureted 366s. We leased one that actually had a Holley 4 barrel and tubular headers new from the factory. They made a bunch with square bore Holleys and headers in the late 80s on straight trucks, dump trucks etc. I am pretty good and driving economically. I am wondering if there is anything I can do mechanically short of installing an overdrive which would basically never pay for itself on this truck.
 

shiftpro

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I have probably a million miles driving carbureted trucks of various sizes with manual trannys, from a 1961 Ford C-600 to 1980s GMCs with the last of the carbureted 366s. We leased one that actually had a Holley 4 barrel and tubular headers new from the factory. They made a bunch with square bore Holleys and headers in the late 80s on straight trucks, dump trucks etc. I am pretty good and driving economically. I am wondering if there is anything I can do mechanically short of installing an overdrive which would basically never pay for itself on this truck.
You can scrap the box and build a simple lightweight flat deck. Use cedar for the deck boards, they will resist rot and weigh almost nothing. The weight savings will help significantly.
 

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Run what you have access to manifolds flow well, the ram horn style flow a little better. I picked up a fancy set of 50 state legal shorties from Edelbrock. But I only picked them up because I have a Edelbrock top end and fuel pump and wanted everything to match. In retrospect, long tubes flow more everywhere=HP/TQ/MPG; but may not provide as much ground clearance. If you do come to the dark side, make sure you use a high quality set of locking header bolts, and make sure you are confident swinging a ballpein hammer to get the spark plug clearance you want. Be sure to true them up pre install. And don't drop oil on any ceramic coating - ask me how I know. If you stay with manifolds, I have had good luck with powder coating or even 2 stage PPG turns out sharp.
 

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