Title says it all. Wrapping them would be cheaper, and work more efficiently, but I've heard of wraps destroying headers due to the heat basically melting them, and causing blowouts. I have Dynatech LT's and I want to get some opinions. I would rather wrap for the cost/efficiency improvements.



thanks

P.s. the headers are stainless steel. I don't know of any ss headers that fail due to wrapping, but I don't know alot about this in general.

 

FWIW, I have the Dynatechs on my car now. I had them coated before putting them on, and I think it is worthwhile to do so (if you plan to EVER use a wideband O2 on your car, get an extra bung welded in before coating, don't ask me how I know). If you have them coated you won't have any problems with O2 sensor heating issues, etc. I recommend against using header wrap in any fashion. SS headers WILL RUST, and the wrap wicks/traps moisture against them. Also, with the tight clearances for these headers the wrap would be a pain anyway. Just my opinions, of course....I am very satisfied with my Dynatechs.

 

I just bought a used set of B&B shorty headers and they are also Stainless T-304 I believe...I have considered both of your thoughts mentioned above but am going with nothing on them...From running SS headers in the past on several cars- I noticed that they dicipate heat more effectively then steal or other metal headers do...jetcoating also smooths out the internal pipe as well (as long as they coat the inside) so the more porus non SS variety benefit from this. I have seen many a less quality header turn bright red from heat at the bends...never on a SS set... just an FYI- I owned a 95 Mustang GT, they had factory SS shorties on them...and they were great- never had violent heat temps under the hood...and they had no coating at all...

You may consider some wrap around the body pan...as the heat from long tubes can rise up into the passenger compartment...but I think you will be OK otherwise...

 

Dynatech told me never to wrap headers because there is no place for the heat to go and it will ruin the headers.

 

I wouldn't wrap them or get them coated. They should work fine on their own. I have wrapped headers before and it sucks, I have had issues with spark plug clearances, etc. The wrap will trap water and cause oxidation (It may be stainless, but if you leave water on it w/o a way to evaporate it will still cause problems)

If I had to choose, I would ceramic coat before I wrap.

Chris

 

I had my Dynatech's polished and ceramic coated. They look great, and there's no noticeable increase in underhood temps.

 

IMO, Ceramic.
Fred

 

Just had my Kooks coated and this is the best way to go!

 

There's some kind of Lizard ceramic paint that works up to 800 degrees. I see it advertised in Race Car Engineering magazine all the time. Seems pretty cool if you want to coat more than just the headers. I've been thinking about getting a tub of the stuff and going buckwild with it.

 

Ceramic in and outside. Or naked, just don't wrap them.

 

Look at the following link. Interesting info. Ceramic coat, definitely

Performance Coatings

I plan on getting some for my aluminum backbone and other undercar areas....considering the IC-1 for $60/quart.

The industry has come a long way with coatings and you don't have to bake them all on anymore. Many of the hi-temp coatings are water soluble and air dry Worth considering if on a budget (like me!)

 

That's the line of product that I had my dynatechs coated with (inside and out)....cermachrome is what they call their header coating...of course it does have to be baked on. They have a very good line of products and a fair number of "approved applicators" for baked on coatings.

 

Excellent information, thanks.

 

Modern ceramic coatings will drop temps and improve flow over SS headers everytime. SS is a great material for those who don't want to have to worry about it, but the additional coating is worth it in many ways. I think the off-road X-pipes should be coated as well, as this may be able to reduce heat in the console area dramatically.

Todd

 

Another point to consider when thinking about coatings: when you coat the exhaust manifold/header, the heat stays in the exhaust gas and helps light off the cats quicker which ain't a bad thing.

Also, BSME2000, you might want to look into the behavior of exhaust gasses through the exhaust pipe. The gas energy content is essentially equal to the enthalpy and the kinetic energy (entropy is also involved, but let's not go there....it's negligible).

This is the normal condition for gas flow in insulated pipes. The gas expands as it uses pressure to overcome friction during its journey along the pipe. The various effects interact with each other as follows :

* The reduction in pressure causes a reduction in density.
* The reduction in density causes the velocity to rise.
* The rise in velocity increases the kinetic energy of the gas.
* To maintain the energy balance, the rise in kinetic energy is compensated for by a reduction of the enthalpy.
* The reduction in enthalpy causes a change in temperature.
* The temperature drop in turn increases the density and so partially offsets the increase in kinetic energy.

Futher enthalpy losses through the exhaust system (heat loss) increases the gas density further and drains kinetic energy further. Friction losses also increase as the density increases.

The kinetic energy is what scavenges the exhaust out of the engine. The momentum (kinetic energy) of the gas creates a low pressure at the closed exhaust valve, helping to suck the exhaust out. This scavenging efficiency is enhanced further by headers. So, to make use of all the kinetic energy in the exhaust gas, it’s best to minimize exhaust gas cooling.

Smokey Yunick used to preach this concept and regularly wrapped his exhaust systems to insulate them; that was before ceramic coatings. But as mentioned, wrapping increases material heat, traps moisture increasing risk of corrosion, and I don’t think this was mentioned but corrosion is accelerated at higher temperatures so wrapped components will corrode faster.

Internal and external coating with ceramics protects the metal two ways: protects it from heat and protects it from elements that create corrosive reactions. If you have the money, it makes sense to internally and externally coat the exhaust system to conserve the kinetic energy.

 

dayum! Your makin' me wanna coat EVERYTHING in the exhaust circuit!!

Thanks for the reply.

 

I was looking at the wrap since I live in a VERY dry climate and have had no problems with it in the past. Seems to be used extensivly on turbo cars around here. I was thinking it would also reduce some of the valve train noise, any thoughts on that?

thanks

pete

 

Why not try the paint I mentioned? You'll get better coverage, and you won't have to worry about rust. It'll probably be easier to apply too.

 

thats what i would do.