Heat shielding for headers

[Hawk]

I am going to be installing Belanger headers and was looking for a fuse box heat shield. I checked with Doug Shelby however he does not have any in stock and does not know when he will get more. Does anyone know of another one from anyone else? Also are there any other heat shields that I should install with the header installation. I have checked out a few other threads with the areas to wrap with the heat shielding tape. If anyone has recommendations for heat protection send it along. Would removing the insulation from under the hood make any difference or will it cause problems with the paint and or clear bra on the hood?
Any help is appreciated
Thanks
Dennis

[darbgnik]

I think Mod Mafia and Calvo both supply the heat shield:

https://modmafia.com/products/viper-titanium-fusebox-heatshield

Can't comment on pricing....

[Black Pearl]

I have heat covers on 1 of my Vipers headers.

ATP Advanced Thermal Products Irvine, CA
https://atpwrap.com/

Viper Gallery
https://atpwrap.com/alloy-racing-covers/dodge-viper-gallery/
https://atpwrap.com/alloy-racing-covers/dodge-viper-srt-10-gallery/

[Pappy]

Easy to build yourself. I built this one out of carbon fiber, but would have just as easy to build out of aluminum. I first covered it with gold reflective covering, but when I checked the temps there was very little difference between the outside (header) side and the fuse box side. I added DEI floor and tunnel shield to the outside of the lower half of the shield, and that took care of the problem. On another car, I built an aluminum shield between the headers and the dry sump oil lines and filters. I added DEI "form-a-shield" to the header side - good to 1400 degrees of direct contact.

50409

50410

[Arizona Vipers]

Are you going to track this or just street? Wrap your O2 sensors too, that's much more important.

[Hawk]

I use the car mostly on the track. Will removing the insulation under the hood help or just cause other problems with the paint and or clear bra?

[Arizona Vipers]

I use the car mostly on the track. Will removing the insulation under the hood help or just cause other problems with the paint and or clear bra?

Do yourself a favor and just wrap the headers and be done with it. If this is a hard track use car you will melt everything eventually, wrapped or not. Just wrap the headers, get the heat out the exhaust pipes instead of having 1000* headers cooking everything and raising your engine oil and coolant temps. Wrapping my headers what the single best track mod I ever did.
I removed my insulation and it hasn't discolored my hood yet. That insulation is there to help put out engine fires as well btw. The plastic that holds it on melts during an engine fire and it becomes a blanket.

[Aevus]

Do yourself a favor and just wrap the headers and be done with it. If this is a hard track use car you will melt everything eventually, wrapped or not. Just wrap the headers, get the heat out the exhaust pipes instead of having 1000* headers cooking everything and raising your engine oil and coolant temps. Wrapping my headers what the single best track mod I ever did.
I removed my insulation and it hasn't discolored my hood yet. That insulation is there to help put out engine fires as well btw. The plastic that holds it on melts during an engine fire and it becomes a blanket.

Arizona, is there any cons wrapping the headers? Heard it has to be rewrapped every 2 years or so

[J TNT]

I've heard some use Swain coatings with good success , I haven't tried them yet .
I wrapped headers with DEI when it first came out and crystalized and ruined my headers in just 6 months , DEI offered me new wrap and I had to buy new headers on my dime .
They have since rewritten their install procedure .

https://swaintech.com/race-coatings/

[SilveRT8]

When installing Belanger headers on my Gen5, the Mechanic suggested to add some Gen3 manifold heat shields and he modified them to fit over the headers. I also have Spark plugs heat socks.
He is a former Mechanic for a Viper racing team.

[Arizona Vipers]

Arizona, is there any cons wrapping the headers? Heard it has to be rewrapped every 2 years or so

Everyone will say they will corrode faster, but mine have been wrapped for 5 years hard use, no issues yet.
Before this I had them coated and the coating burned off in a few track sessions. It didn't do much anyway. You can literally touch a wrapped header, it'll be 100*, touch a coated header and your fingers will stock to it with 3rd degree burns lol

[Aevus]

Everyone will say they will corrode faster, but mine have been wrapped for 5 years hard use, no issues yet.
Before this I had them coated and the coating burned off in a few track sessions. It didn't do much anyway. You can literally touch a wrapped header, it'll be 100*, touch a coated header and your fingers will stock to it with 3rd degree burns lol

yeah I don't believe in coating efficiency... Thermal insulation requires a lot more that just 1mm or so of material, whatever it is.

Wrapping makes a lot more sense BUT it could be ''too much'' efficient and cause problems to the headers themselves, that's what i'm worried about. On the other hand it's very tempting for both lowered temp under the hood AND scavenging effect.

Arizona, did you notice any gain in HP (butt dyno or measured) before/after wrapping the headers?

[Hawk]

What did you use to wrap the headers that held up well? I certainty like the idea, even if I need to replace the headers in a few years, it’s a lot easier than all the damage that you could end up fixing from the heat
Thanks
Dennis

[ViperGeorge]

I rarely post on this site any longer as there have been too many rude postings about members, including me. Every so often though I see a person asking a question that maybe I can offer some input on. This is one of those cases. What I will say below may not be believed by everyone and that's ok, just please keep any rude replies in check.

Wrapping your headers will certainly reduce under hood temperatures and cause the heat to mostly exit the exhaust as AZ states. However, there may be another option you should consider. A friend of mine and I, both with Gen Vs with 9 liter-extreme upgrades and headers, had the headers Swain coated prior to installation. Swain coating is used by NASCAR and is not like the other ceramic coatings people have applied to headers. It is much thicker.

I have been absolutely amazed at the temps of my Swain coated headers after coming off the track. Primary tubes are typically between 140 and 160 degrees measured using my laser pyrometer. This is true on my car and my friends. High Plains is our home track and we run mid 1:5x lap times which for High Plains is considered pretty quick. As comparison my brake rotors are typically around 400 to 500 degrees using the same pyrometer. While I have not been brave enough to actually touch the headers I can put my hand pretty darn close to them with out feeling excessive heat.

Now I know there have been postings on this site about the proper way to measure temperatures using thermal sensors and imaging but even if my pyrometer is not as 100% accurate I don't believe it could be many hundreds of degrees off. To me temps in the mid 100s seem pretty good and appear consistent with the feel of the parts. I can't even get near my rotors coming off track but I can put my hand within inches of the primaries on my headers.

My engine temps on my ACR never get above 220 even on a very hot day. Usually the temp is around 210. On my old TA2 with headers and no 9 liter upgrade, temps would regularly hit 245 on track and stuff would melt. While I think that Swain coating is something you should research, regardless of whether you decide to wrap your headers or coat them I would still insulate things under hood especially the fuse box and wire harnesses. This is an extra level of safety.

[Hawk]

George
I really like the idea of the Swain coating. I did order the headers with a factory applied ceramic coating inside and out, should I try and cancel the coating from Belanger or can they coat over it? If you don’t mind me asking what was the ballpark cost? Did you also do the down pipe between the headers and cats?
Thanks for the help
Dennis

[Arizona Vipers]

yeah I don't believe in coating efficiency... Thermal insulation requires a lot more that just 1mm or so of material, whatever it is.

Wrapping makes a lot more sense BUT it could be ''too much'' efficient and cause problems to the headers themselves, that's what i'm worried about. On the other hand it's very tempting for both lowered temp under the hood AND scavenging effect.

Arizona, did you notice any gain in HP (butt dyno or measured) before/after wrapping the headers?

Well just by having lower temps underhood that's a lot more horsepower. These cars pull timing at 201* coolant!

[Arizona Vipers]

What did you use to wrap the headers that held up well? I certainty like the idea, even if I need to replace the headers in a few years, it’s a lot easier than all the damage that you could end up fixing from the heat
Thanks
Dennis

Just DEI stuff- https://www.amazon.com/gp/product/B002R4U72I/
It's held up very well. We have had it off a few times and the headers showed no corrosion, but like you said if I had to replace the headers every 5 years due to this it's worth it obviously.

[Arizona Vipers]

I rarely post on this site any longer as there have been too many rude postings about members, including me. Every so often though I see a person asking a question that maybe I can offer some input on. This is one of those cases. What I will say below may not be believed by everyone and that's ok, just please keep any rude replies in check.

Wrapping your headers will certainly reduce under hood temperatures and cause the heat to mostly exit the exhaust as AZ states. However, there may be another option you should consider. A friend of mine and I, both with Gen Vs with 9 liter-extreme upgrades and headers, had the headers Swain coated prior to installation. Swain coating is used by NASCAR and is not like the other ceramic coatings people have applied to headers. It is much thicker.

I have been absolutely amazed at the temps of my Swain coated headers after coming off the track. Primary tubes are typically between 140 and 160 degrees measured using my laser pyrometer. This is true on my car and my friends. High Plains is our home track and we run mid 1:5x lap times which for High Plains is considered pretty quick. As comparison my brake rotors are typically around 400 to 500 degrees using the same pyrometer. While I have not been brave enough to actually touch the headers I can put my hand pretty darn close to them with out feeling excessive heat.

Now I know there have been postings on this site about the proper way to measure temperatures using thermal sensors and imaging but even if my pyrometer is not as 100% accurate I don't believe it could be many hundreds of degrees off. To me temps in the mid 100s seem pretty good and appear consistent with the feel of the parts. I can't even get near my rotors coming off track but I can put my hand within inches of the primaries on my headers.

My engine temps on my ACR never get above 220 even on a very hot day. Usually the temp is around 210. On my old TA2 with headers and no 9 liter upgrade, temps would regularly hit 245 on track and stuff would melt. While I think that Swain coating is something you should research, regardless of whether you decide to wrap your headers or coat them I would still insulate things under hood especially the fuse box and wire harnesses. This is an extra level of safety.

Swain is indeed probably the best coating out there!

[Steve M]

George
I really like the idea of the Swain coating. I did order the headers with a factory applied ceramic coating inside and out, should I try and cancel the coating from Belanger or can they coat over it? If you don’t mind me asking what was the ballpark cost? Did you also do the down pipe between the headers and cats?
Thanks for the help
Dennis

I've seen the Swain coatings before and wasn't really interested, but decided to look at it again for grins. Looks like a Belanger exhaust right at the top of their page about their exhaust coating:

https://swaintech.com/race-coatings/race-coating-descriptions/white-lightning-exhaust-coatings/

If you read on that page, it looks like media blasting is required to get a good bond. If it were me, I'd ask Belanger to NOT coat their headers before shipping if that's what you intend to do. Good luck getting him to agree to that though.

The one thing that has always turned me off to their coating is that it is white, and to me, that is not a good look. To be blunt, it would keep me from trying their product.

But then I decided to pull my head out of my own ass and actually read their page, specifically this part:


Because White Lightning™ really is a ceramic, it is not possible to offer color choices like you can get with paint based coatings. However, the white textured finish of White Lightning™ makes it an ideal base for a good high temperature paint if you want to change the color of the coating. The high temperature paints bond well to the natural textured finish of White Lightning and the paint will not impact the effectiveness or durability of the White Lightning™ coating.

To me, it would be worth a shot to try their coating system. If it were me, I'd be painting it black (or maybe silver) before installing.

I've only had first hand experience with Jet-Hot coatings on one of my previous vehicles, and it didn't do shit for keeping the temps down.

[Arizona Vipers]

On my turbo build, we are getting everything shielded in inconel with these guys- https://turbosource.com/pages/inconel-custom-made-heat-shielding-ordering-form
Scroll to bottom to see their shielded headers.
Also, I know Nth makes full inconel headers if you can afford them hehe

[ViperGeorge]

George
I really like the idea of the Swain coating. I did order the headers with a factory applied ceramic coating inside and out, should I try and cancel the coating from Belanger or can they coat over it? If you don’t mind me asking what was the ballpark cost? Did you also do the down pipe between the headers and cats?
Thanks for the help
Dennis

Not sure I remember the cost but I think it was around $600 plus shipping. I would not have the factory apply a coating. Get the headers un-coated and then send to Swain. We had ARH drop ship our headers directly to Swain. I did the primaries and collector but not the cats or mufflers. I was told that doing the cats might cause them to get too hot inside. I don't know if that is true or not though. Swain may say something about that on their website.

[Jack B]

A little input on measuring the header temps with an infrared camera. Most shinny surfaces have a low emissivity, therefore, they read low. To get a true temp, put a dab of black grill paint on the spot you want to measure.

[ViperGeorge]

A little input on measuring the header temps with an infrared camera. Most shinny surfaces have a low emissivity, therefore, they read low. To get a true temp, put a dab of black grill paint on the spot you want to measure.

Thanks Jack. The Swain coating is not shinny though. It is a very dull (flat actually) whitish/gray. Would this make much difference?

[Jack B]

Thanks Jack. The Swain coating is not shinny though. It is a very dull (flat actually) whitish/gray. Would this make much difference?

That would probably show a true temp.

[ViperTony]

Just DEI stuff- https://www.amazon.com/gp/product/B002R4U72I/
It's held up very well. We have had it off a few times and the headers showed no corrosion, but like you said if I had to replace the headers every 5 years due to this it's worth it obviously.

AZ did you use their HT Silicone Spray on the wrap?

[Whiskey]

Does anyone have pics of the Gen3 heat shields on the Gen5? I was thinking the bolt pattern is different.

[blingnoring]

i have stock headers and got the high flow cats and belanger mufflers from JonB and sent them to Swain. They charged me $550 to do the cats and mufflers. I believe the guy's name there is George, he said it would be fine applying the coating on the hi flow cats. And because JonB painted the exhaust tips black for me, you cannot see any of the white coating. I didn't measure any temps but feeling my sills before and after is a huge difference. Now they are just warm instead of very hot to the touch.

I did ask if i get headers down the road would i be able to wrap the headers on top of their coating and he did not recommend doing that

[Arizona Vipers]

AZ did you use their HT Silicone Spray on the wrap?

No, what does that do?

[J TNT]

No, what does that do?

If you have a flammable fluid like oil or gas dripping on the exhaust wrap it will help to Not absorb into the wrap and minimize fire potential .

[Aevus]

seems like a good idea

https://www.designengineering.com/hi-temp-silicone-coating-spray-black/

...but as many other things: out of stock.

[Aevus]

https://www.youtube.com/watch?v=cIBE0xYDm7E&t=71s

[Hawk]

Finally received my headers. I sent them out to Swain Tech for the coating. The coating is thick and has an orange peel surface it took the flat black high temp paint great. I will get them installed in the next couple weeks. I will post temp readings after my next track day. I’m hopeful that the coating will keep the temp down. The cost to coat the headers as well as the collector pipes with shipping $698

51008

51009

[Hawk]

After

51010

51011

[J TNT]

Thanks for posting , looking forward to see what the Temp. Delta is .

[Whiskey]

When installing Belanger headers on my Gen5, the Mechanic suggested to add some Gen3 manifold heat shields and he modified them to fit over the headers. I also have Spark plugs heat socks.
He is a former Mechanic for a Viper racing team.

How did he med them to fit? I didn't see an easy way to make it work with my ARH headers.

[Whitey]

After

51010

51011

May I ask what black coating you used?

[Hawk]

Rust-Oleum high heat

https://smile.amazon.com/dp/B08MWX88MV?psc=1&ref=ppx_yo2_dt_b_product_details

[Whitey]

Thanks

[Hawk]

I have some preliminary temperature readings for the headers with the Swain coating. It was only spirited street driving with an ambient air temperature of 50 degrees. I’m hoping someone can post temperature readings under the similar conditions with the stock exhaust manifolds and or temperature readings on the track with stock manifold and or headers to get a base reading to determine how the coating is preforming. For reference the headers and collector pipes are coated with Swain coating ,the hi-flow cats and factory muffler have no coating
Reading at top of headers close to plugs 397 degrees
The collector pipe close to the O2 sensor 470 degrees
The body side sills at the hottest spot 148 degrees

Once I get a day at the track I will post reading under those conditions
Thanks
Dennis

[ViperGeorge]

I have some preliminary temperature readings for the headers with the Swain coating. It was only spirited street driving with an ambient air temperature of 50 degrees. I’m hoping someone can post temperature readings under the similar conditions with the stock exhaust manifolds and or temperature readings on the track with stock manifold and or headers to get a base reading to determine how the coating is preforming. For reference the headers and collector pipes are coated with Swain coating ,the hi-flow cats and factory muffler have no coating
Reading at top of headers close to plugs 397 degrees
The collector pipe close to the O2 sensor 470 degrees
The body side sills at the hottest spot 148 degrees

Once I get a day at the track I will post reading under those conditions
Thanks
Dennis

Much higher than what I am seeing. Does anyone know what header temps are without coatings?

[Hawk]

I’m wondering if the street driving could be showing higher temps as there is stop and go. On the track there is constant flow of air thru the grill even though you are working the motor harder?

[ViperGeorge]

I’m wondering if the street driving could be showing higher temps as there is stop and go. On the track there is constant flow of air thru the grill even though you are working the motor harder?

Maybe.

[Lawineer]

No way. Tracking will have much hotter exhaust. It's both running richer (so fuel in the exhaust), harder, faster, and it has very quick, very big throttle position changes (which again causes exhaust in the primaries).

Think of it this way.
Roughly 1/3 of the energy goes to moving the car
1/3 goes to wasted heat in the fluids (oil, coolant, etc)
1/3 goes to exhaust

When does coolant get the hottest? Driving around town or at the track?

[Arizona Vipers]

No way. Tracking will have much hotter exhaust. It's both running richer (so fuel in the exhaust), harder, faster, and it has very quick, very big throttle position changes (which again causes exhaust in the primaries).

Think of it this way.
Roughly 1/3 of the energy goes to moving the car
1/3 goes to wasted heat in the fluids (oil, coolant, etc)
1/3 goes to exhaust

When does coolant get the hottest? Driving around town or at the track?

Yeah agreed. If you really want to get it hot, lower speed tracks where you are in 2nd gear most of the track at high RPM's, that will get your oil to 250 pretty quick. You're using about 50hp on the street, on the track you're using all the horsepower you have. Again if you want "cold" headers wrap them. I can literally touch mine with my fingers meaning they are probably 150*

[ViperGeorge]

I will have to check my header temps again at the track. A friend and I both have 9L-Extremes with Swain coated ARH headers. Cats and Mufflers are not coated. We checked both cars immediately after coming off of track after about 25 minutes. Primary pipes were around 140-150 degrees using a laser pyrometer. Both our headers are the flat white that the Swain coatings come in naturally. While I didn't try to touch them I could easily put my hand within a couple of inches of the pipes without noticing any significant heat. I couldn't get close to my rotors, they were hot, like 500 degrees. There was a clear difference between the heat of the headers and the heat of the header primary pipes.

[J TNT]

To get an accurate measurement it’s best to scan a black object even if you just spray a small area that you are scanning.

[Arizona Vipers]

I will have to check my header temps again at the track. A friend and I both have 9L-Extremes with Swain coated ARH headers. Cats and Mufflers are not coated. We checked both cars immediately after coming off of track after about 25 minutes. Primary pipes were around 140-150 degrees using a laser pyrometer. Both our headers are the flat white that the Swain coatings come in naturally. While I didn't try to touch them I could easily put my hand within a couple of inches of the pipes without noticing any significant heat. I couldn't get close to my rotors, they were hot, like 500 degrees. There was a clear difference between the heat of the headers and the heat of the header primary pipes.

Our rotors get to over 1000 degrees very easily and even higher with slicks. I can't even take my front wheels off for at least an hour after a session

[Lawineer]

Yeah agreed. If you really want to get it hot, lower speed tracks where you are in 2nd gear most of the track at high RPM's, that will get your oil to 250 pretty quick. You're using about 50hp on the street, on the track you're using all the horsepower you have. Again if you want "cold" headers wrap them. I can literally touch mine with my fingers meaning they are probably 150*

Yup!
When we were developing the TT powertrain for the S7, we wanted turbos before the cats for a multitude of reasons, the least of which was not lag/response of the turbos. At the time, that was a tall order for emissions with a big bore 7 liter engine. The big issue with cold start is in the name- the cats aren't hot and working effectively yet. Putting a turbine in the middle to remove heat from the exhaust compounded that.
We tried coatings left and right. They really don't do anything. Then we wrapped them and it made a world of difference. Then I think they changed the cam or something and it all became a moot issue. The car actually made way more power than we expected on 8psi so they dropped it to 4psi, added compression and I *think* removed the intercooler. Then they added the intercooler and cranked it to 8psi for the competition variant with 1000hp.

It makes sense when you think about the physics of it. Heat transfer (or resistance to, aka insulation) is basically thermal conductivity of the material times the thickness of the material. Which makes sense if you think about it. Insulation that is twice as thick is going to insulate twice as well. Well, coatings have really good (low) thermal conductivity, but they're like 0.01" thick or something. You're probably talking 10x that for the thickness of fiberglass wrappings (which are also pretty good insulators).

[Lawineer]

Our rotors get to over 1000 degrees very easily and even higher with slicks. I can't even take my front wheels off for at least an hour after a session

I waited a good 30-45min and damaged my clearcoat when I put the tie down through the front wheels to tie it down on the trailer, lol.

[Arizona Vipers]

Yup!
When we were developing the TT powertrain for the S7, we wanted turbos before the cats for a multitude of reasons, the least of which was not lag/response of the turbos. At the time, that was a tall order for emissions with a big bore 7 liter engine. The big issue with cold start is in the name- the cats aren't hot and working effectively yet. Putting a turbine in the middle to remove heat from the exhaust compounded that.
We tried coatings left and right. They really don't do anything. Then we wrapped them and it made a world of difference. Then I think they changed the cam or something and it all became a moot issue. The car actually made way more power than we expected on 8psi so they dropped it to 4psi, added compression and I *think* removed the intercooler. Then they added the intercooler and cranked it to 8psi for the competition variant with 1000hp.

It makes sense when you think about the physics of it. Heat transfer (or resistance to, aka insulation) is basically thermal conductivity of the material times the thickness of the material. Which makes sense if you think about it. Insulation that is twice as thick is going to insulate twice as well. Well, coatings have really good (low) thermal conductivity, but they're like 0.01" thick or something. You're probably talking 10x that for the thickness of fiberglass wrappings (which are also pretty good insulators).


You've got some cool stories! On our turbo time attack project we are shielding everything with Inconel. Machined formed stuff (Like in the pic below) for the turbos, manifolds, piping etc, and we'll cut the sheets in house and glue/rivet on the smaller stuff. It's probably going to cost $7000 or so. The fastest time attack cars in the country come down to one thing only, how much horsepower you can keep cool for one lap. Nothing else matters.



51265

[13COBRA]

You've got some cool stories! On our turbo time attack project we are shielding everything with Inconel. Machined formed stuff (Like in the pic below) for the turbos, manifolds, piping etc, and we'll cut the sheets in house and glue/rivet on the smaller stuff. It's probably going to cost $7000 or so. The fastest time attack cars in the country come down to one thing only, how much horsepower you can keep cool for one lap. Nothing else matters.



51265

And how much longer until we get to see this monster in action?

[Arizona Vipers]

And how much longer until we get to see this monster in action?

It'll be done by Viper Rendezvous, but I don't think that's a good event for this car with very limited passing and it being so hot there in June. Even if the car could handle the heat, I can't LOL
Should have the built motor back next weekend and all the plumbing etc was already made and installed before, so just needs to go back in and then lots of tuning etc.
We still need to install the ACR brakes and aero. I'm sure this thing is going to be a nightmare to fine tune on the track, and it's hot here already, 100* today. So might wait until after summer to get it on track.

[13COBRA]

It'll be done by Viper Rendezvous, but I don't think that's a good event for this car with very limited passing and it being so hot there in June. Even if the car could handle the heat, I can't LOL
Should have the built motor back next weekend and all the plumbing etc was already made and installed before, so just needs to go back in and then lots of tuning etc.
We still need to install the ACR brakes and aero. I'm sure this thing is going to be a nightmare to fine tune on the track, and it's hot here already, 100* today. So might wait until after summer to get it on track.

Bring it out to the Midwest it's still cool here, heck I'm shopping for oil heaters haha

Diesel fuel will only run you $3500-4000.

[Arizona Vipers]

Bring it out to the Midwest it's still cool here, heck I'm shopping for oil heaters haha

Diesel fuel will only run you $3500-4000.

I'm doing Road Atlanta in a couple weeks and did the math, it's going to be around $4500 for diesel there and back. Insanity.

[13COBRA]

I'm doing Road Atlanta in a couple weeks and did the math, it's going to be around $4500 for diesel there and back. Insanity.

Yes, yes it is.

I was pretty gung-ho about NASA nationals this year, but that much in fuel is a joke. I can spend $4500 and rent out a track for an entire weekend.

[Lawineer]

You've got some cool stories! On our turbo time attack project we are shielding everything with Inconel. Machined formed stuff (Like in the pic below) for the turbos, manifolds, piping etc, and we'll cut the sheets in house and glue/rivet on the smaller stuff. It's probably going to cost $7000 or so. The fastest time attack cars in the country come down to one thing only, how much horsepower you can keep cool for one lap. Nothing else matters.



51265

Why inco?
We used plenty of inco in the S7TT and even the fighter jet engines for high temp stuff ($25 one time use bolts and $20 nuts left and right), but it was because it didn't lose strength until higher temps compared to stainless. It's just high nickel stainless, really. It's not some sort of great insulator. Its maybe a touch better than 304.

The main reason for shiny metal on the outside of the insulation is to reflect/reduce radiant heat transfer. It's not for structural integrity. That's why the old school insulation wrap has a shiny side and then the fiberglass side.

What I assume you're doing it basically using air an insulator. Trapping that air in there so the air heats up and doesn't flow around the engine bay- which is a very good thing. Air is a good insulator- if you can keep it from moving (or moving out of the engine bay).



only downside of wrap is fire hazard. It attracts and soaks up oil. Oil and high heat dont mix. If you spill oil on it (oil change) you're in a world of headache. And headers aren't easy to rewrap while they're on a car!

[Lawineer]

Fun/nerdy trivia:
Anyone know how they keep the exhaust of a fighter jet from melting/catching fire, etc. when the afterburners are on? It's about 3500-4000 degrees F in modern fighters. Keep in mind, it doesn't just need to withstand those temps- it needs to maintain strength. The exhaust of the plane is under a lot of pressure at "WOT."

[13COBRA]

Fun/nerdy trivia:
Anyone know how they keep the exhaust of a fighter jet from melting/catching fire, etc. when the afterburners are on? It's about 3500-4000 degrees F in modern fighters. Keep in mind, it doesn't just need to withstand those temps- it needs to maintain strength. The exhaust of the plane is under a lot of pressure at "WOT."

No...but definitely subscribing to find out how.

[Steve M]

Fun/nerdy trivia:
Anyone know how they keep the exhaust of a fighter jet from melting/catching fire, etc. when the afterburners are on? It's about 3500-4000 degrees F in modern fighters. Keep in mind, it doesn't just need to withstand those temps- it needs to maintain strength. The exhaust of the plane is under a lot of pressure at "WOT."

I'd guess some combination of using the fuel as a heat sink, and maybe carefully directing some of the cold ambient air in the right spots.

[Pappy]

Fun/nerdy trivia:
Anyone know how they keep the exhaust of a fighter jet from melting/catching fire, etc. when the afterburners are on? It's about 3500-4000 degrees F in modern fighters. Keep in mind, it doesn't just need to withstand those temps- it needs to maintain strength. The exhaust of the plane is under a lot of pressure at "WOT."

Okay, I can probably help with this from an operator's, not designer's, prospective. I flew fighter aircraft with afterburners for over 30 years, including 15 years and 2000 hours in the F-15, and I never had an issue with heat-caused failures in the afterburner nozzles. When a modern fighter engine is at idle, the afterburner (AB) nozzles are wide open like the left nozzle in the F-15 photo below. As you advance the power to 100% (military power without afterburner), the nozzle closes like the nozzle on the right to cause a venturi to increase trust of the exiting exhaust gas. Then, when you light the burner, the nozzle swings wide open to accommodate the tremendous "explosion" of fuel dumped into the engines turbine plume. There is airflow around the outside of the burner nozzles, and if you are in afterburner you are probably hauling ass and there is plenty of airflow. With that said, I have been in tail slides while in full AB with no issue. The only potential issue is disrupted airflow to the intake and you can get a compressor stall or flameout. If you look at a jet engine exhaust, the plume (flame) is a lot like a torch. The real hot spot(s) are further out the plume like a gas torch. (See last photo) If you look at the tailpipe of the A4N (non-afterburner) below, notice the extended tail pipe. This was to put the "hot spot" further behind the aircraft so a heat-seeking missile warhead's explosion would be further behind the aircraft and less likely to damage the engine or airframe. You will have to pardon this A-4 pilot's landing technique, but as the philosopher Shaggy once said, "It wasn't me".

Pappy

51266

51267

51268

[Lawineer]

I'd guess some combination of using the fuel as a heat sink, and maybe carefully directing some of the cold ambient air in the right spots.
Pretty close on the air! Imagine each flat flap with a hot side (exhaust) and cold side (opposite side). They run cold air cross the cold side, and through the flap, into the cold side through tiny little holes. The holes are just the right size and spaced just right to create a laminar sublayer of air across the hot side. It basically creates a boundary layer of air to protect the metals from the exhaust gasses. Pretty trick stuff!

Of course, it's far from a perfect insulator so they also use high nickel metals as well.




Pappy, that's super cool. Dream job stuff right here! The Raptor has large flat "wings" near the exhaust to shield the exhaust gasses. Thermal/heat detection is the new radar since these things are basically invisible to radar. It has the radar signature of a literal bumble bee. It also help thermal signature (and range) that the Raptor can super cruise (>Mach 1) without igniting afterburners.

For people unfamiliar with it, check out this video starting at 50 sec. Thing looks like it's drifting in some of the turns :lol:

https://youtu.be/QVio1GpCdoA?t=52