Are Headers REALLY Worth It?

[toobroketoretire]

Back in the early 1960's headers first appeared on some drag and track racing cars and header manufacturers have been aggressively promoting them ever since. They promise huge gains in torque at all rpm levels but oddly enough not a single car in the world has ever come equipped with them. We have all read many articles and seen many videos about how effective headers are but those articles and videos have been produced by the headers manufacturers; not disinterested 3rd party laboratories who have no financial gain in the outcome of the tests. As a Mechanical Engineer I know how easy it is to show bogus "before and after" dyno tests in which the "before" is run at a 75% throttle opening and the "after" is run at 100% to show the amount of improvement. So are headers REALLY worth it? When pondering that question the old saying "buyer beware" comes to my mind....................

 

[Hib Halverson]

(snip) As a Mechanical Engineer I know how easy it is to show bogus "before and after" dyno tests in which the "before" is run at a 75% throttle opening and the "after" is run at 100% to show the amount of improvement. (snip)

Ok. So you, who claims to be an ME, are implying on a public forum that header companies and others who test headers falsify data.

Please post any fake dyno tests which you have as evidence to support your statement.

Also, since you're an ME know knows how to do it, tell us how to fake a dyno test at 75% throttle.

 

[Vettehead Mikey]

but oddly enough not a single car in the world has ever come equipped with them.

'82 Corvettes did.

 

[Hib Halverson]

Yes, 82s had tubular stainless steel "shorty" headers.

Some other Corvette have had either tubular or fabricated exhaust manifolds welded-up from hydroformed stainless steel. The LT5s had them. There were some C5s with them. The C6 Z06es and C6 ZR1s had them, too.

GM offered aftermarket headers as a factory option with some G1 Z/28s.

Cast iron headers were available in the 60s on some Pontiac engines. Big Block Corvettes had what amounted to a shorty tri-y header only in cast iron.

 

[toobroketoretire]

Also, since you're an ME and know how to do it, tell us how to fake a dyno test at 75% throttle.

It's real simple to fake dyno tests. All you have to do is run a comparison "before" test of ram horn manifolds at a 75% throttle opening then run an "after" test of your headers at a 100% throttle opening and PRESTO. You show a significant gain. And I'm not claiming the header folks fake their dyno tests but rather explaining how easy it is to fake those dyno tests for the sole purpose of making money.

So what exactly is a "header"? Well, a header is an exhaust manifold that has been given a fancy name because it's made from steel tubing. But regardless of whether it's made from cast iron or aluminum or steel tubing it's still a manifold, right? And the advertisers know fancy names demand higher prices.

Simple logic tells me any product that is half as good as the manufacturer claims would be on every engine in the world.

 

[Vette me]

The sound of music

To be all fair there are those who prefer headers to stock manifolds just be cause of the sound and look, rather if they make the vehicle perform better then stock or not BUT being a retired mechanic who has built more classic and hot rods since the 70's to just last year 2015 I can tell you that if you want a true performing enhanced header type then you need to go through Sanderson headers. Sanderson's has been not just dyno testing their products but also testing them on the street and at the track since day one. Look them up, they can also make a set of headers just the way you want them.

 

[toobroketoretire]

Chinese Headers Have Flooded The Market

I was cruising the internet a few days ago and ran across a Chinese website in which they're selling headers for only $50 a pair in lots of 100 pairs. And how are Sanderson's 4 into 1 headers any different from all the other 4 into 1 headers? I would think all 4 into 1 headers would sound exactly the same regardless of who makes (or claims to make) them. I know mufflers can make a big difference in sound but I can't imagine how headers could when using OEM style quiet mufflers.

 

[toobroketoretire]

Stock "Replacement" Mufflers

When I began restoring my 454" powered '71 six years ago I bought a set of "stock replacement" mufflers from Corvette Central; thinking the big blocks would use less restrictive mufflers. But when I road tested it I found it fell on it's face at only 3500 rpm and immediately suspected the new mufflers caused the enormous drop in power. I cut one of the mufflers open and found it was an ordinary muffler but with a huge 2-1/2" inlet pipe necked down and wended onto the muffler's 2" inlet pipe and a 2" outlet pipe necked down and welded onto the muffler's 1-3/4 outlet pipe. And the internal crossover pipe was only 1-5/8" in diameter. So with 230 cubic inches breathing thru the tiny 1-5/8" crossover pipe it's no wonder it fell on it's face.

Next I tried a set of 40-Series FlowMasters but with my TH700R4 and 3.08 gears the drone inside the cabin was unbearable at cruising speeds. A drone so powerful I could feel it in my chest. Then I decided to make my own mufflers but using big 2-1/2" tubing thruout and they did the trick (sorry I don't have the step-by-step pictures any more). My home made mufflers have the same 17" shell length as the OEM mufflers but with the big 2-1/2" tubing in the inlet, crossover, and outlet and my exhaust tips also having the big 2-1/2" tubing it'll easily rev to 6000 rpm with no trouble whatsoever. They are about 4 times as loud as the OEM but 1/4th as loud as the 40-Series FlowMasters. The 2-1/2" tubing has a .070" wall thickness and the shells are ,060" thick so my mufflers will last a lifetime on 91 octane unleaded.

When I was a kid in the 1950's spark plugs only lasted 10,000 miles and exhaust pipes, mufflers, and tail pipes only lasted 2 years because of the high sulfur content in the gasoline; sulfur that became sulfuric acid when mixed with water. And it was the sulfuric acid and lousy oil bath air filters that destroyed cylinder walls and piston rings in only 90,000 to 100,000 miles and required 3000 mile oil changes to get rid of the acid and dirt. Sulfur and lead was used in the gasoline as lubricants so once the sulfur and lead was eliminated and the vastly superior pleated paper air filters came onto the scene our engines last 3-4 times longer than they did.

 

[Hib Halverson]

It's real simple to fake dyno tests. All you have to do is run a comparison "before" test of ram horn manifolds at a 75% throttle opening then run an "after" test of your headers at a 100% throttle opening and PRESTO. You show a significant gain. And I'm not claiming the header folks fake their dyno tests but rather explaining how easy it is to fake those dyno tests for the sole purpose of making money.(snip)

You said previously you are an ME and implied that you know how to fake dyno tests. Have you ever actually run a car at "75%" throttle on a chassis dyno then compared the torque curve to one run at 100%? If so, please post some results so we can all better understand your position.

So what exactly is a "header"? Well, a header is an exhaust manifold that has been given a fancy name because it's made from steel tubing. But regardless of whether it's made from cast iron or aluminum or steel tubing it's still a manifold, right? And the advertisers know fancy names demand higher prices.

I want to make sure I understand your statements...
1) You are saying that the only difference between headers and stock manifolds are the materials, ie: cast iron vs. tubular steel. Is that correct? 2) Also, you are publicly accusing aftermarket header makers of misrepresenting their products as just exhaust manifolds made of a different material and which have been renamed, but offer no useful change in the performance of an engine on which they are installed? Is that correct.

if I am reading your statements correctly., can you supply some evidence to support those statements in the form of dyno tests done by yourself?

 

[dougelam]

Come on guys, I believe we are being played!
He is just either trying to stir up trouble or he really doesn't know what the difference is.
The majority of our members know what and how headers work, he is just fishing
Like Hib said, show us some numbers
Or better yet show us some ME knowledge other than false accusations

Sent from my SM-T530NU using Tapatalk

 

[Antz81]

I was cruising the internet a few days ago and ran across a Chinese website in which they're selling headers for only $50 a pair in lots of 100 pairs. And how are Sanderson's 4 into 1 headers any different from all the other 4 into 1 headers? I would think all 4 into 1 headers would sound exactly the same regardless of who makes (or claims to make) them. I know mufflers can make a big difference in sound but I can't imagine how headers could when using OEM style quiet mufflers.

The length of the tubes will have an effect on it, as well as the difference in the length of the tube for each cylinder. On a good header all tubes will be the exact same length. if they are different lengths then performance will suffer.

 

[toobroketoretire]

More Power And Better Fuel Mileage

How many times have we heard the claim "More Power And Better Fuel Mileage"? Since I was a kid I have seen dozens of products making that claim but when those products were tested under laboratory conditions not a single one lived up to it's promises. Headers are beneficial under high rpm track racing conditions where mufflers aren't required but for street engines I can't see how any gain could be realized. When I see new vehicles come off their assembly lines equipped with headers I'll jump on board but until that happens I'll stick with my trusty cast iron exhaust manifolds.

 

[toobroketoretire]

H Pipes And X Pipes

Being an engineer I know H pipes and X pipes are much more beneficial at solving the 8/4 and 5/7 pressure pulses problem. The problem with C3's is they have transmissions bolted to the rear of the bell housing so X pipes can't be mounted real close to the engine like they need to be. To mount an X pipe behind the rear axle is about as good as joining the mufflers together. You'd get a small reduction in noise but no gain in power. That's why I chose to mount my H pipe right behind my torque converter where it does the most good.

 

[toobroketoretire]

Believing Advertising

Most people are real suckers when it comes to believing the advertising they are constantly exposed to. Like the advertising that claims huge power gains by bolting something onto the OUTSIDE of your cylinder heads (???). I was always taught power was made inside the cylinders and unless something can force more air into the cylinders it won't do diddly squat. If you want to sell something give it a different name and looks then make claims about it that aren't the least bit true. If a product is only half as good as the manufacturer claims every engine in the world would be equipped with it. Oddly enough every car in the world is still equipped with those "inefficient" cast iron exhaust manifolds that rob your engine of the power it should be making. It's probably a government conspiracy to prevent excessive horsepower and fantastic fuel mileage. Something to ponder, huh?

 

[RedHot85Vette]

'82 Corvettes did.

Yep! from a special magazine from 1985 about Vettes from '53 to '95, about the '82 said: "...and Stainless Steel FreeFlow exhaust headers..."

The magazine article about the '84 said: "blah, blah, blah...stainless steel exhaust system...".

 

[RedHot85Vette]

Headers, What Do You Think of These?

Good Day! I hope all are enjoying a pleasant one. Found these on eBay, has anybody used them, if so, what's your review... any performance gains? Are they worth the cost and efforts to install them.


Best Regards,


John


Chevy SBC 350 1 5/8" Block Hugger Black Exhaust Headers


Item # 201449143694

Chevy SBC 35 1 5 8" Block Hugger Black Exhaust Headers | eBay

 

[Tom Bryant]

Those look a lot like what you should already have. Beginning in 1981 Corvette switched to tubular exhaust manifolds and I'm pretty sure they continued through 1996, the last year before the LS series of engines. Here is a photo of a 1981 manifold, stripped of all of it's shields and AIR tubes, mounted on my 1969 stepside. These have a 2" outlet. Beginning in 1982 they went to a 2.5" outlet.

Tom

 

[RedHot85Vette]

Those look a lot like what you should already have.

Yep! I'm 99.999% sure you're right unless they had some weird lets build a freaky engine day at bowling green. I'm not able to visit my own car at the moment so I googled and ebay'd things and although all the manifolds I saw were shielded, I believe they looked a lot like yours underneath. Nope, I don't think it would be worth the time, trouble, and money to change anything and I don't believe there would be much if any higher performance to be gained from the headers. Headers may look nice and give a different tone to the exhaust... I don't know about other Headers, but I don't think these Shorty things would be worth it.

Related: I read in a magazine from 1985, (which was mostly about the '85, but the mag is just chock full of info about Vettes and Vette-Mania from '53 on...) that the '82 had "stainless steel freeflowing exhaust manifolds" and that the '84 had a "stainless steel exhaust system.

Thanks for your informative & Intelligent response,

John

​

 

[toobroketoretire]

Headers do have their advantage in off road track racing where mufflers are not required. To be beneficial headers must meet these three conditions:

1. Wide open throttle

2. High rpm

3. Headers must be run OPEN to the air....................not blowing thru mufflers!

As it's against the federal noise standards street cars can't run open headers and that's why not a single car in the world has ever come with them.

 

[toobroketoretire]

Those look a lot like what you should already have. Beginning in 1981 Corvette switched to tubular exhaust manifolds and I'm pretty sure they continued through 1996, the last year before the LS series of engines. Here is a photo of a 1981 manifold, stripped of all of it's shields and AIR tubes, mounted on my 1969 stepside. These have a 2" outlet. Beginning in 1982 they went to a 2.5" outlet.

Tom

My '82's stainless steel tubing exhaust manifolds exit at 2" then immediately step up to 2-1/2". The tubing is only 1-3/8" in diameter; certainly not a "performance" size by today's standards.