Landracing Forum
Tech Information => Technical Discussion => Topic started by: Jerry O on May 08, 2009, 12:15:28 AM
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Trying to finish all the engine items on my liner and was planning to get the headers ceramic coated. Since this is my first LS project I decided to look at some photos of several cars to see what most are doing. Mostly liners and lakesters, I found a lot of them have the headers wrapped instead of coated. Now when I talked with the people that is doing the coating, they told me the ceramic coating would give me better thermal protection than wraps. So what is the best way to go. The headers will be on a completely inclosed streamliner, motorcycle engine, non turbo charged (for now) Thanks for any info.
JerryO
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Tried both on my street MG.
I'd wrap 'em. Less heat in the engine compartment.
Ceramic coating is great for protecting the headers, and you'll get many more years out of them, but it doesn't insulate as well as a wrap or a blanket.
And for what it's worth, wrapping is quieter.
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coat then wrap.... the inside coating will kinda protect the welds then wrap the outside to keep the heat down inside the engine compartment.....temperature controll is a big problem in an enclosed liner..... unwrap the pipes after the season cuz the wrap will cause the pipes to rust and check for possable cracks cuz the wrap holds in the heat and causes the metal to get brittle..... throw away after 2 years and start all over....
Kent
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if it is a closed limited space vehicle, use the coating if you don't mind everything melting :| We always wrapped, then learned the ceramic would keep the pipes cooler :roll:
Most of the wiring insulation was heat damaged, the Morse cable we used for throttle got stiff, the little shift kill box melted and killed, and the paint bubbled..... other than that it sure made the pipes look nice....
We wrap... once was enough for us.... a couple of hundred for coating only cost us a couple of days of racing and about a grand in parts....
Want to guess my answer... I would only wrap in a small closed area. If you have external pipes... zoomies... nothing within a couple of feet of the pipes go ahead and try the ceramic route.
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Thanks for the info guys. From what you guys are telling me, it looks like wrapping them will be the best way to go. I do have some cables and wiring that could be damaged if I don't. Since I plan on adding a turbo next year I will probably not have them coated also. Since I am on a tight budget, that will save me a couple hundred bucks. Thanks again for your help and hope to be running soon , although I am only three months behind schedule. I was told that when I set a finish date and a how much it would cost me to do this project, I needed to double that. Boy were they right!
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Only double on the money? You are doing good. :-D
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We found the biggest heat problem was at shut down and when stopped. There has to be a way for the heat to get out or it can just sit there and bake. When we ran turbos, we had a little fan inside the engine compartment that would turn on when we clicked off. Every car is differant of course and you will just have to keep an eye on it.
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Remember to water soak the wrap right before you put it on. Half lap it and put it tight. I use stainless wire to hold it on instead of clamps. I like to double wrap it for the first 6" out of the head. The small fan is an excellant idea in a liner.............Good Luck
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Remember to water soak the wrap right before you put it on. Half lap it and put it tight. I use stainless wire to hold it on instead of clamps. I like to double wrap it for the first 6" out of the head. The small fan is an excellant idea in a liner.............Good Luck
jimmy six,
Another little trick I do is to spray paint my header wrap with Black High Temp BBQ Paint for that Custom Black Matte Finish and it help repels the Salty water off the wrap a little better :cheers:!
I've used EGT TURBO TIMER'S and they work pretty good on some car,and trucks.
Good Luck,
Kaz...
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Richard...... Did you have the fan blowing on the headers or just moving air inside the engine compartment. Thanks.....JerryO
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What results has anybody had with stainless steel headers ?
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John..... I have built lots of stainless headers for Indy cars and nascar. In NASCAR we had no problems but in the Indy cars we had to make insulated boxes that completely wrapped around the headers. We even had fresh air going in the boxes and exhaust ducts coming out. Even with that when the car came off the track during practice we had to remove the rear body work as soon as the car stopped. It would burn the body work in about one minute if we did not. The stainless headers will handle the extreme heat and last a lot longer with a wrap but will not be much different than mild steel headers as far as radiant heat with out any type wrap.
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Ceramic coat, then jacket the whole header system in SS or inconnel (depending on EGT) with enough room between the jacket and header to have some portion of the airflow going through the jacket. I like wrapping, the only problem is that oil tends to soak the wrap after a while. This defeats the insulation and creates a safety hazard in a fire where the "insulation" turns into a long term wick for everything it has absorbed.
The best insulation is fully sealed inside an SS or inconnel jacket, that way it never picks up oil and other crud.
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Jerry 0 It was kind of blowing on the headers but directed across them and toward a naca duct. Seemed to work.
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For areas where you need to protect "stuff", add THIN aluminum heat shields, and make them as large as possible (surface area). Make areas of the heat shield reach into areas that are NOT direct hot. By using very thin aluminum, the heat transfer (in terms of distance/time) will be very quick (into areas that are cooler.) You can move the heat any direction you want, regardless of airflow, and even sink it into components that can accept some extra heat for a while.
You will be amazed how much heat you can "de-concentrate" (there's a word for ya'). If you chicken out and use thicker aluminum, all bets are off..... it's not about resisting the heat, it's about capturing it, spreading it out and moving it FAST.
Look under any modern car, how the heat from multiple catalytic converters is managed, with 1800 degree parts... 1 inch from your ankle! Also, the texturing you see is another aid to rapidly balancing the heat. Crawl under the junkers at the pick-a-part and buy all the interesting shapes and lengths you can.....I've got them under my street rod and there is NO problem with heat coming through my floor. I have not added any "insulation" (which often turns into a a heat sink, in my opinion).
Regards, JimL
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My headers are 2 1/4" ss which I polished to minimize radiant heat and I'm planning on jacketing with larger ss tubing . Thinking about ss wool between the header and jacket .
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John;
If you can seal both ends of the header sleeve you could pull a vacuum on the space between the header tubes and the sleeves. That would prevent lots of heat loss. Not easy to do, though.
Regards, Neil Tucson, AZ
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Just remember when you wrap that the headers need to be run hot to burn off the skin oils, any crap that touched or wiped on the wrap... If you paint with anything, they will smoke like crazy for a while.... it can be a good test for your firewall but will scare the crap out of folks with all the smoke.
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McMaster Carr #9379k93 is 1/2" thick 3" wide soft ceramic pipe insulation with an aluminum jacket I'm going to insulate my streamliner headers with . Good to 2300 deg , $12 per 12 ft roll . #76035A65 is the 500 deg glass reinforced 2 mil aluminum foil tape I'm sealing the seams with . Low heat loss and won't any absorb oil .