how much heat is generated by headers?

[bradvette]

What kind of heat under the hood is generated by putting on a set of exhaust headers? I've heard anywhere from very little - to alot. 1990 L98.

Also....how long on average does a pair of Hooker longtube headers last before replacement is necessary? What are the telltale signs that replacement is needed?

Thanks!

 

[rocklyons]

header heat

I can't answer your questions with specific answers however I will give my opinion.

Ten years and 120 K miles ago I put a pair of headers on my 1972 El Camino. I noticed no increase in underhood temp (as shown on oil temp or water guages), and they are still in reasonably good condition.

As a side bar comment, headers don't generate heat, they just radiate heat transfered from the exhaust valves. Stock iron exhaust manifolds do the same thing so I don't see why headers would cause the car to run hotter than stock exhaust.

The increased horsepower from headers comes from reducing the back pressure on the engine created by the restricted air flow thru the exhaust manifolds. Increased airflow might even reduce the temperatures.

Just a thought, I may be wrong.

Rock

 

[Edmond]

Like Rock said, headers themselves won't generate heat. They'll transfer heat just like the exhaust manifolds.

I think for long term use, you should get the headers coated.

 

[elseyj]

You'll find the headers store a lot less heat than the big cast iron heat sinks.

 

[DR.68]

I agree with Edmond
JetHot Coat the Headers
They will last longer & the jet hot will cut down on heat transfer. They look great too.

 

[vader86]

get them ceramic coated, that will reduce the heat a little, and will definitely make them cool off faster

But, you should put heat-shielding material on everything under the car which would be affected. I'm sure they sell some shielding tape or insulation at Autozone, then cover the starter and all the oil cooler and transmission cooler lines especially. I would also wrap the fuel lines.

 

[bradvette]

Thanks everyone, sounds great. Yes, they'll be ceramic-coated for sure. The heat sheilding on some of the components is also a great idea

 

[vettered91]

Three weeks ago since I installed Hooker long headers in my LT1 and everything is melting under my hood! They really get H O T!!! and everything near them. (two spark plugs cables burned in the test trip) But there is a world of difference with and with out them on, power you really can feel (I have no cats and a nice set of Magnaflows)

In the first oportunity I'm going to take them off to wrap them with Thermo-Tec Header Wrap (Summit THE-11002) because I don't think I can find down here someone to make the ceramic coating job, besides I'm not too sure the ceramic will be enough to keep the heat inside (I don't have any experience with ceramic so don't take my word for it)

Right now I have them part-wraped and is not enough, is my every day car and it's almost impossible to do it well with the headers on, so maybe next weekend Ill do it. Maybe vader or somebody else here can tell us about ceramic and heat.

I love my headers and if I have to do it all again I'll do it with out thinking!!!

 

[Edmond]

Three weeks ago since I installed Hooker long headers in my LT1 and everything is melting under my hood! They really get H O T!!! and everything near them. (two spark plugs cables burned in the test trip) But there is a world of difference with and with out them on, power you really can feel (I have no cats and a nice set of Magnaflows)

In the first oportunity I'm going to take them off to wrap them with Thermo-Tec Header Wrap (Summit THE-11002) because I don't think I can find down here someone to make the ceramic coating job, besides I'm not too sure the ceramic will be enough to keep the heat inside (I don't have any experience with ceramic so don't take my word for it)

Right now I have them part-wraped and is not enough, is my every day car and it's almost impossible to do it well with the headers on, so maybe next weekend Ill do it. Maybe vader or somebody else here can tell us about ceramic and heat.

I love my headers and if I have to do it all again I'll do it with out thinking!!!

There was a member who posted something along the lines that wrapping your headers will create long term problems. I can't remember exactly what the problems were but I think it had something to do with rust and deterioration.

 

[Gman]

If you're in a hot, humid spot, don't wrap them. The moisture tends to build between the header and the wrap and accelerate rust and shorten life. I had full length uncoated headers on an '84 and they began rusting soon after installing them. Ceramic coating your headers will reduce underhood temps over stock manifolds. Do anything you can to get them ceramic coated!!!

 

[vettered91]

Hi Edmond,

I believe the problem can be rust, but maybe not with some kind of coating like ceramic, that's why I'm taking my time to fix the heat matter. It is a real pain to put them on (I did it my self) but I like very much the way the engine performs with them. I'm very conected with the metal industry here in Guadalajara and I'm sure I'll find an easy, cheap & fast way to solve the problem, I just need some time, maybe ceramic, maybe to chrome, to galvanize, teflon or something else and then maybe (if there's need) to wrap them. (I know it may void the guarantee)(and they look like mummys)

I'll keep you informed!

 

[Edmond]

Hi Edmond,

I believe the problem can be rust, but maybe not with some kind of coating like ceramic, that's why I'm taking my time to fix the heat matter. It is a real pain to put them on (I did it my self) but I like very much the way the engine performs with them. I'm very conected with the metal industry here in Guadalajara and I'm sure I'll find an easy, cheap & fast way to solve the problem, I just need some time, maybe ceramic, maybe to chrome, to galvanize, teflon or something else and then maybe (if there's need) to wrap them. (I know it may void the guarantee)(and they look like mummys)

I'll keep you informed!

Hi,

Yes, definitely have them ceramic coated but don't wrap them. It'll cost you less headache in the long run. The higher cost of ceramic coating will definitely be more beneficial in terms of heat dissipation and maintanence.

I was told that Hooker makes extremely good headers that fit as well as anyone elses, if not more.

Good luck to you and yeah, the exhaust manifolds really stink!:L

 

[vettered91]

I forget to tell you that I need more time because the need to heal the hundred wounds in my hands after the header job!!! (They look like I had a fight with an angry cat)

 

[Vettart]

Sorry to hear the cat won. I have had ceramic coated headers on my '79 for 5 years now. Excellent mid-range performance aside, they look just as good today as they did when they were put in. They are Dynamax, as are the mufflers. Great sound. A few extra bucks for ceramic coating is worth every penny.

 

[Dave C. '04 Z06]

If you're thinking of shorty headers, don't bother as your L-98 manifolds are practically shorty headers already.

I put hooker shorty headers on my LT-1 about 2 months ago and the underhood temps didn't go up noticably. I haven't had anything get too hot or melt or anything. Everything seems normal except I have a little more power.

-Dave C.

 

[vettered91]

Sorry to hear the cat won. :L

Yes; You're right! About the cat (and the ceramic coat)

Now I don't have any doubts about it, first oportunity I'm going to get them coated. Five years it's sufficient proof for me!

 

[Ken]

When I first saw this question, I thought of how difficult it is to answer because of all of the variables involved, i.e., engine rpm, engine load, ambient temperature, coated vs. non-coated, etc.. However, yesterday I was watching someone unwrap a box of Sanderson headers and I'll be darned if it didn't say right there on the side of the box: "The temperature at the tubes can reach as high as 1000° F."

So, I guess you now have a definitive answer.

 

[-=Jeff=-]

Moved to C4 Mods

 

[vettered91]

"The temperature at the tubes can reach as high as 1000° F."

I'm almost sure the two spark plug wires burned (and one finger)in the very first test where " 750° F proof" so no doubts for me about it!

ad :L

 

[steve1ph]

hookers

i to have the hooker long tube headers. not really that hard to install as opposed to every thing iv heard. the only gripe i have is that so far i have to tighten the bolts every so often. they are fixing to come off and get the smog crap cut off, different bolts and gaskets and then get coated. i personaly noticed hotter temps. how much should i expect to pay for the coating? oh yea the guys at the local speed shop told me also not to waste my time with the shorties for the same reason mention above. good luck.