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  #1  
Old 05-31-2016, 04:14 PM
English Power English Power is offline
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Default Headers Are Worthless On Street Engines

We Europeans have always known steel tubing exhaust manifolds (aka "headers") are worthless when used on street engines unless they are run OPEN ("uncorked"). And as you can't run OPEN headers on the street they are nothing but worthless ornaments with a fancy name and an even fancier price.

You gullible Americans have been convinced headers actually "produce" power when in fact they don't produce anything. Power is produced inside the cylinders and once the hot exhaust gasses get blown out of the cylinders the power "event" is over.

When "headers" were first used in the early 1960's their collectors had 4" diameter cover plates attached so they could be opened "uncorked" so the exhaust gasses could be blown to the open air. But sometime after the 1960's ignorant people began attaching their exhaust pipes directly to the ends of the collectors which made the headers worthless other than looking racy.

Headers are intended to be run OPEN to bypass the restrictions of the exhaust pipes, mufflers, and tail pipes. But as street engines require mufflers what good are the headers when they have to be run corked?

So why do you goofy Americans love your headers so much?
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Old 05-31-2016, 05:24 PM
flash flash is offline
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Im sure Im in the minority but I hate headers ,they leak ,make it hard to change plugs ,and you normally have to ding them to fit.I only have one truck that still has headers and it came with them when I bought it .
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  #3  
Old 05-31-2016, 06:31 PM
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Hank70SS Hank70SS is offline
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Quote:
Originally Posted by flash View Post
Im sure Im in the minority but I hate headers ,they leak ,make it hard to change plugs ,and you normally have to ding them to fit.I only have one truck that still has headers and it came with them when I bought it .
Only leaks I've had are from stock manifolds on a 454 in our old motor home. They heated up so much they cracked the manifolds and busted the bolts. After installing a set of headers, no more leaks and a definite increase in power. Just my experience John and I do run headers on the Chevelle.
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Old 05-31-2016, 07:37 PM
carpoor carpoor is offline
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Great first post.
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Old 05-31-2016, 06:08 PM
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chevymaher chevymaher is offline
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Quote:
Originally Posted by English Power View Post

You gullible Americans have been convinced headers actually "produce" power when in fact they don't produce anything. Power is produced inside the cylinders and once the hot exhaust gasses get blown out of the cylinders the power "event" is over.
True but if the gasses can't be scavenged out effectively. The cylinder is not empty. You can't fill it if it isn't empty. So the cylinder can't produce peak power if it isn't a complete fresh charge of gas and air. Burnt gasses do not magically reburn.

May want to check a few dyno test out of stock exhaust and then changed to headers with matched exhaust systems. Before getting rude.

There is another chevelle site Team Azzhole go there and start things. Here we like to get along.
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Old 05-31-2016, 06:28 PM
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Hank70SS Hank70SS is offline
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Headers definitely reduce back pressure on the engine. The headers cool the exhaust gases faster than stock manifolds so they condense quicker and create less back pressure. If you think back pressure is a good thing then stuff some raw potatoes up your tail pipes and go for it.
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Old 06-06-2016, 10:47 AM
English Power English Power is offline
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Originally Posted by Hank70SS View Post
Headers definitely reduce back pressure on the engine. The headers cool the exhaust gases faster than stock manifolds so they condense quicker and create less back pressure. If you think back pressure is a good thing then stuff some raw potatoes up your tail pipes and go for it.

Please explain to me how headers reduce back pressure when the cause of the back pressure (the restrictive exhaust pipes, mufflers, and tail pipes) is still there? Headers are only effective when they are run open or did you Americans forget that little detail? And then headers are only effective when the engine is being run at full power and high rpm; something street engines rarely (if ever) do.

Steel tubing exhaust manifolds do have their place in off road track racing events where mufflers aren't required but when used on street legal vehicles they offer no benefit at all. Just ornaments with a cool name and hefty price tag.
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Old 06-06-2016, 02:38 PM
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chevymaher chevymaher is offline
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Quote:
Originally Posted by English Power View Post
Please explain to me how headers reduce back pressure when the cause of the back pressure (the restrictive exhaust pipes, mufflers, and tail pipes) is still there? Headers are only effective when they are run open or did you Americans forget that little detail? And then headers are only effective when the engine is being run at full power and high rpm; something street engines rarely (if ever) do.

Steel tubing exhaust manifolds do have their place in off road track racing events where mufflers aren't required but when used on street legal vehicles they offer no benefit at all. Just ornaments with a cool name and hefty price tag.
Same car same exhaust just headers added. Looks like across the board power increase to me.


Don't know about where you live but things do get run wide open here alot.
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Old 06-06-2016, 06:13 PM
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Hank70SS Hank70SS is offline
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Quote:
Originally Posted by English Power View Post
Please explain to me how headers reduce back pressure when the cause of the back pressure (the restrictive exhaust pipes, mufflers, and tail pipes) is still there? Headers are only effective when they are run open or did you Americans forget that little detail? And then headers are only effective when the engine is being run at full power and high rpm; something street engines rarely (if ever) do.

Steel tubing exhaust manifolds do have their place in off road track racing events where mufflers aren't required but when used on street legal vehicles they offer no benefit at all. Just ornaments with a cool name and hefty price tag.
Pretty simple physics. The extremely hot exhaust gases leaving the cylinder create a lot of pressure in the manifolds or headers. As they cool and they cool down much faster in headers than in most stock manifolds, the pressure is reduced. Again, pretty simple, headers have much more exposed surface area to to cool the exhaust gases. Blow up a balloon with very hot air then cool it down to freezing and watch the balloon collapse.

Headers cool the exhaust gases faster, once they're cooled down they require less volume and the rest of the exhaust can handle it. Remember that everything that leaves the exhaust had to come in through the carburetor, which is as at ambient temperature. Know look at the ventures in your carburetor and compare the volume to that of the exhaust system. Simple, the sooner you cool the exhaust gases the easier it is for the rest of the exhaust system to handle it.

If you don't believe, fine. There are plenty of dyno runs available to prove it.
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Old 06-01-2016, 09:29 AM
mestorod70 mestorod70 is offline
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Goofy troll
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