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Heat Shrouds

jukelemon

New member
Louisville, KY
Aircraft Year
1977
Aircraft Type
112B Hot Shot
Reg Number
N377SB
Serial Number
526
Hi all.

I just heard you may be able to run 4 heat shrouds as opposed to just 2. Any one else doing this?

Thanks
 
Re: Heat Shrouds

Jason,Jason,Jason, first it’s too cold out,now your airplane is too hot, which is it?
Want to sell that plane? It’s only 7 above up here, I could use a warmer cockpit!
All in fun friend...
 
Re: Heat Shrouds

Jason,Jason,Jason, first it’s too cold out,now your airplane is too hot, which is it?
Want to sell that plane? It’s only 7 above up here, I could use a warmer cockpit!
All in fun friend...
? Not sure I follow Rolf.

I am talking about getting MORE heat with adding in 2 more shrouds for the exhaust pipes :D

The Hot Shots have a heat shroud/exchanger (?) on 2 exhaust pipes as a way to get cabin heat. I heard you can use 4 to get more.

Hope you're well.
 
Re: Heat Shrouds

I also have the 112 hot shot. Carl told me there was no reason I couldn’t have 4 shrouds instead of 2. I’m going to do this.
 
Re: Heat Shrouds

I also have the 112 hot shot. Carl told me there was no reason I couldn’t have 4 shrouds instead of 2. I’m going to do this.
Agree...

Is there a layout/drawing for using 4 as opposed to 2?

Did you already order yours?

Thanks Chip
 
Re: Heat Shrouds

Ok... I see a callout for 4 on my HS manual.

Carl: is there a reason one would not do 4?

Thanks
 
Re: Heat Shrouds

Ok... I see a callout for 4 on my HS manual.

Carl: is there a reason one would not do 4?

Thanks

The early original design used 4. I'm not sure if any of these still exist - I haven't ever seen one. The later, improved design, uses just 2. I'd have to see a picture of yours to know which you have.

There are better, and worse ways to plumb them that make a big difference in their performance.
 
Re: Heat Shrouds

The early original design used 4. I'm not sure if any of these still exist - I haven't ever seen one. The later, improved design, uses just 2. I'd have to see a picture of yours to know which you have.

There are better, and worse ways to plumb them that make a big difference in their performance.
Thanks Carl.

I have 2 now. Can you please explain the better and worse ways?

When I look on the Right side, there is a really steep bend from the cowl intake to the shroud. The SCAT has to really rise quickly to get to the shroud intake.

Thanks
 
Re: Heat Shrouds

Thanks Carl.

I have 2 now. Can you please explain the better and worse ways?

When I look on the Right side, there is a really steep bend from the cowl intake to the shroud. The SCAT has to really rise quickly to get to the shroud intake.

Thanks

Can you send some pics?
 
Re: Heat Shrouds

N1182J had the 4 on when Sven bought her down to Georgia. Said that I did not need 4 and the extra would get in the way when working on the plane.
We took them off but unfortunately I did not get any pics.

I have the parts but would have no idea how to fit. I will look at old pics and see if I can find anything.

Life is a barrel of fun.
 
Re: Heat Shrouds

N1182J had the 4 on when Sven bought her down to Georgia. Said that I did not need 4 and the extra would get in the way when working on the plane.
We took them off but unfortunately I did not get any pics.

I have the parts but would have no idea how to fit. I will look at old pics and see if I can find anything.

Life is a barrel of fun.
Ah...that explains it.

Thanks Ken.

One of things I was telling Carl is that the intake to shroud takes a crazy S turn. I bet it loses 40% or more airflow because of that. It HAS to get up there but if I could attach a rounded elbow to the shroud...now I think that would make a significant difference.
 
Re: Heat Shrouds

Have some pics. Amazing how Sven can still help us with his great documentation,

In pic 1 I am assuming that one is for the defrost????????? It is on the pilots side and obviously gives off heat. Or there may have been a second one that side,

Will look for more pics.

Life is a barrel of fun.
 

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Re: Heat Shrouds

Thanks Ken.

The 1st pic...

Looks like the heat vents are off i.e. I see the line going up which I assume is going to the T then to both the Defroster gate and the heat vents. But I dont see the heat sent at all.

Did he run one heat shroud for the Defroster and one for the heat?

On a different note...that is a damn clean engine.
 
Re: Heat Shrouds

one more pic
 

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Re: Heat Shrouds

Thanks Ken.

The 1st pic...

Looks like the heat vents are off i.e. I see the line going up which I assume is going to the T then to both the Defroster gate and the heat vents. But I dont see the heat sent at all.

Did he run one heat shroud for the Defroster and one for the heat?

On a different note...that is a damn clean engine.

82J is S/N 155. The heat is ducted through the firewall differently than yours.
 
Re: Heat Shrouds

The early original design used 4. I'm not sure if any of these still exist - I haven't ever seen one. The later, improved design, uses just 2. I'd have to see a picture of yours to know which you have.

I have two now, but originally had 4. I'll see if I can dif up an old photo.

The original design of the shrouds were different -- and pretty much ineffective. And there was only one air intake. The move from 4 to 2 with a second NACA was a huge increase in heat for me. But it is not nearly enough on really cold days and/or altitudes. 4 would be better. Better still would be something that could take better advantage of the heat that the turbo generates.

Regards,
Neal
 
Re: Heat Shrouds

Thanks Ken.

The 1st pic...

Looks like the heat vents are off i.e. I see the line going up which I assume is going to the T then to both the Defroster gate and the heat vents. But I dont see the heat sent at all.

Did he run one heat shroud for the Defroster and one for the heat?

On a different note...that is a damn clean engine.
Jason,

1182J (and 1286J for that matter) is a much earlier Commander than yours. As a result the heater routing is different, so I would suggest that you could not route the SCEET in quite the same manner.

Ken,

It appears there is a typo in your signature. N1182J is a 1974 Commander.

Regards,
Neal
 
Re: Heat Shrouds

Jason,

1182J (and 1286J for that matter) is a much earlier Commander than yours. As a result the heater routing is different, so I would suggest that you could not route the SCEET in quite the same manner.

Ken,

It appears there is a typo in your signature. N1182J is a 1974 Commander.

Regards,
Neal
Thanks Neal and understood. That makes sense.

Yeah...as I get a bit obsessive on this...I am seeing what seems to be several challenges in the air flow.

That big S turn from cowl intake to the 1st shroud is not something a SCAT hose should do on its own i.e. it cannot bend that much.

Like I mentioned, I am betting that I am losing 40% + of air flow because of that alone.

Now, I know I cannot change the cowl intake AND I know I cannot change the heat shroud intake angle.

So... I am hoping that it is legal/an option to attach a small 45 deg coupler to the intake of the shroud so that the cowl to shroud SCAT is more linear/unobstructed. I am thinking that alone would be a huge win for the airflow.

Also, I am hoping that it is legal/an option to find not a better couple for the Defrost to Heat SCAT i.e. not a T but an elbow to increase airflow.

I dont know...just thinking out loud..
 
Re: Heat Shrouds

Silicone turbo hoses come in all shapes, sizes, and colors. Just sayin'.
 
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