Hi I'v been reading some people are having problems with headers and are going back from headers to manifolds, I need your opinion on that. What's the problems with headers quality, fitment, leaks, etc? Are manifold beter ? Can I have a good exhaust system with manifold (good sound) with good set of muffler ?
headers vs. manifolds
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On a stock motor cast iron manifolds are fine,, headers are good too but they are a pain to change plugs and keep clean and rust free,, I have headers on my 79 Malibu and had them coated,, I have a pet peev about headers and not coated,, people have a kick !&$ engine bay and rusted headers,, just my problem,, but yeas you can have a good sounding system on cast manifolds,, Matty man
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512 Posts
IMO, cheap headers is where a lot of the problems come in, good headers don't have near the problems and also the advantages.
There are headers and then there are headers. Alas many people (often myself included) purchase based more on price than anything else, and in the case of headers there are a lot of cheap no-name ebay knockoffs out there.
It can be very true that headers make changing plugs difficult, I've had that problem on both my Corvette and my elco. I found for example that getting the plugs out of the vette was far easier to do from below than from above, much the same with the elco at least on a few of them.
It is also true that for a mild motor, old iron manifolds are more than fine, they are quiet and durable beyond compare.
However the moment you start wanting to improve on performance there are few iron manifolds that can be recommended, some may have larger passages but log manifolds regardless of passage size represent a restriction. The old rams horns manifolds found on Corvettes and early chevies are probably among the best iron manifolds you can use, unfortunately the rams horn wont work on an Elco. Old chrysler hemis had great manifolds too IIRC
That leaves us with headers.
Like mentioned above alot of headers now come with thin tubing usually 16-18 ga, and they also usually have really flimsy flanges around 3/16" - For those of you unfamiliar with metal gauge, the bigger the number the thinner the wall my AISC manual shows.
US std ga for uncoated materials.
14ga = .0747" (.0785 zinc coated)
16ga = .0598" (.0635 zinc coated)
18ga = .0478" (.0516 zinc coated)
You can see that 18 ga. is significantly thinner than 14 ga. A quick study of the Jegs catalog on my desk here at work shows the following.
My minimum standards would be nothing less than a 5/16" (3/8" being better) flange and nothing less than 16 ga. (14 ga. would be better.) These would be my recommendations if you were looking for a header.
Different styles of headers may offer better plug access (shorty, block hugger etc..), but for the most part I always assume people are talking full length headers when they discuss plug access woes. Another issue with headers is fitment, I have it on good authority that for example one header manufacturer actually uses the pattern for a full size b-body car to make the 1-5/8" primary headers for an A-body. They determined that the fit was "good enough" which really means constant dimpling to miss stupid things like the steering box which should be easy to miss.
finally a jet-hot or other ceramic coating will increase the apparant tube thickness - they run quieter and cooler than uncoated ones.
It can be very true that headers make changing plugs difficult, I've had that problem on both my Corvette and my elco. I found for example that getting the plugs out of the vette was far easier to do from below than from above, much the same with the elco at least on a few of them.
It is also true that for a mild motor, old iron manifolds are more than fine, they are quiet and durable beyond compare.
However the moment you start wanting to improve on performance there are few iron manifolds that can be recommended, some may have larger passages but log manifolds regardless of passage size represent a restriction. The old rams horns manifolds found on Corvettes and early chevies are probably among the best iron manifolds you can use, unfortunately the rams horn wont work on an Elco. Old chrysler hemis had great manifolds too IIRC
That leaves us with headers.
Like mentioned above alot of headers now come with thin tubing usually 16-18 ga, and they also usually have really flimsy flanges around 3/16" - For those of you unfamiliar with metal gauge, the bigger the number the thinner the wall my AISC manual shows.
US std ga for uncoated materials.
14ga = .0747" (.0785 zinc coated)
16ga = .0598" (.0635 zinc coated)
18ga = .0478" (.0516 zinc coated)
You can see that 18 ga. is significantly thinner than 14 ga. A quick study of the Jegs catalog on my desk here at work shows the following.
- Hedman painted street/strip - 18 ga 3/16" flange (yuk this is super flimsy)
- Hedman elite = 14 ga. 3/8" flange (this is a good set of dimensions)
- Hooker competition = 16 ga. 5/16" (falls between the two)
- Jegs coated - 18 ga.
- Jegs painted - 16 ga. 5/16" (I wonder why there is a difference)
- Dougs 16 ga. 3/8" flanges (quality header)
- Patriot 16 ga. 3/8" flanges
My minimum standards would be nothing less than a 5/16" (3/8" being better) flange and nothing less than 16 ga. (14 ga. would be better.) These would be my recommendations if you were looking for a header.
Different styles of headers may offer better plug access (shorty, block hugger etc..), but for the most part I always assume people are talking full length headers when they discuss plug access woes. Another issue with headers is fitment, I have it on good authority that for example one header manufacturer actually uses the pattern for a full size b-body car to make the 1-5/8" primary headers for an A-body. They determined that the fit was "good enough" which really means constant dimpling to miss stupid things like the steering box which should be easy to miss.
finally a jet-hot or other ceramic coating will increase the apparant tube thickness - they run quieter and cooler than uncoated ones.
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2,247 Posts
Yes, I think most people's complaint is the grungy look of painted headers as they age. Something else to watch out for is the amount of heat created. Can burn through plug wires and temp sensor wires and hoses, etc. Proper heat protection is important, especially plug wire boots. I used dei heat tape and wrapped some wires, plus I wrapped my fuel lines and have not had issues with boiling fuel since.
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Fauxrs - Quote {The old rams horns manifolds found on Corvettes and early chevies are probably among the best iron manifolds you can use, unfortunately the rams horn wont work on an Elco} unQuote
Is the fixment of these an issue for ALL gens?
I'd like to find some nice iron manifolds for my 66 and replace the headers even though 11 months on the road and they haven't loosened yet.
Is the fixment of these an issue for ALL gens?
I'd like to find some nice iron manifolds for my 66 and replace the headers even though 11 months on the road and they haven't loosened yet.
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168 Posts
I personally hate headers on small blocks. They really just make doing things under the hood a pain. on older cars their not generally as bad (I have a fifth gen and hated them) because theres just a little more space. I couldn't get the one header out on the drivers side in mine without pulling either the steering shaft or the oil filter. It was a pain. Just my opinion though
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The problem is that you need the manifolds to angle towards the rear of the vehicle at the exit ends, and not be aimed straight down like many do. That is the main problem in getting them to fit right. The ones that exit stright down run the exhaust right into the crossmember. OOOOPS!
oke:QFT this is the problem with the rams horn manifolds, they dump straight down - right at the crossmember under the motor on most cars other than vettes and the older late 50's cars. In the vette the motor sits behind the front crossmember, it doesnt straddle it like in the elco.The problem is that you need the manifolds to angle towards the rear of the vehicle at the exit ends, and not be aimed straight down like many do. That is the main problem in getting them to fit right. The ones that exit stright down run the exhaust right into the crossmember. OOOOPS!
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You might want to look at the Sanderson cast iron headers. www,sandersonheaders,com
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Just got mine coated $160.00 and these are heavy, can't wait to put them on. I found the easiest way to change plugs is take the tire off. I take off the inner fender well but I have a floor jack and impact wrench so it's no effort or much time and very easy to change all the plugs and inspect the engine at the same time.:beer:
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the rams horn manifolds should fit the 67 and back cars from what i remember. they did a test on the large rams horn manifolds years ago and found they flowed as well as small tube headers.not too shabby .some of the late 60 s early 70 chevy trucks used rams horn mainfolds that turned back to clear the frames on the trucks. it may clear the frame on later elcos not sure though
At the risk of repeating myself, with headers you also have starter problems to look at possibly. I had to raise my engine to remove the starter or the headers for that matter. Luckily I had an old oil pan leak to contend with so I bundled the job and didn't make me too upset about the starter. Still was no breeze and also the starter hits the header so I may be looking at heat problems in the future.
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I have Sanderson Cast Iron headers (okay--a manifold) on my 59
These are great for me.
I had them coated so they are usually okay to touch shortly after shutting the car off.
I have an aversion to maintenance, and continually tightening headers and collectors fall into that category----especially when I am too round to slide under that car.
Had hookers on my old C-10 for years and years.
Got real tired of changing gaskets and fighting to change plugs.
Put the manifolds back on.
Have manifolds on everything and will not go back to headers.
These are great for me.
I had them coated so they are usually okay to touch shortly after shutting the car off.
I have an aversion to maintenance, and continually tightening headers and collectors fall into that category----especially when I am too round to slide under that car.
Had hookers on my old C-10 for years and years.
Got real tired of changing gaskets and fighting to change plugs.
Put the manifolds back on.
Have manifolds on everything and will not go back to headers.
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136 Posts
We have always ran Hedman or Dougs and never had a problem. I have had problems on every set of "bargain" headers I have ever bought. And dont get sucked in by flange thickness because cheap chinese steel is worse than american steel of half the thickness. Just my 2 cents and Sanderson makes wicked good manifolds but they r not cheap.
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