Carb heat insulation material?

69427

The Artist formerly known as Turbo84
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Mar 30, 2008
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Clinging to my guns and religion in KCMO.
Looking for some suggestions for materials to make an insulator under the throttle plate. Excluding the gaskets, I have about 3/16" clearance to put the insulator. I'm looking for something I could pick up at the hardware store, but won't disintegrate being exposed to fuel and vibration.
Suggestions?

thanks,
Mike
 
I curious what the carb temp difference will be with a different insulator than I presently have. For years I've been using a store bought insulator setup, which just consists of alternating layers of gaskets and aluminum stiffening spacers. Regardless of how well the new insulator works, I'm still curious if the setup is still going to get swamped out by the thermal conductivity of the four hold-down studs (which obviously make direct metal contact between the manifold and the carb baseplate). I guess I'll find out soon enough.
 
Mike, since we in Florida I think to block off the entire heat riser cross over passage with plaster of paris, and go to electric choke operation/heater.....obviously if there is stock heat riser valve, it has to be eliminated....

I have done this to a bunch of cars over the years, and cured all sorts of hot running carb problems...

:crutches:
 
I'm using the stainless shield sandwiched between 2 gaskets. The temp differential is significant. I'll have to check it next run. Problem I have is percolating after shutdown. I wonder if the phenolic or wood would stop this.
 
I'm using the stainless shield sandwiched between 2 gaskets. The temp differential is significant. I'll have to check it next run. Problem I have is percolating after shutdown. I wonder if the phenolic or wood would stop this.

It will help.
If anybody knows an electrician, ask him to get you some "red board" from some old switchgear. It's about 3/16 thick, and impervious to 600volts, heat, and flame.
 
maybe you should consider making a heat shield instead of trying to use a spacer. i made a heat shield out of stainless steel for the BG speed demon set up and it did a good job reflecting heat away from the floats. i am not sure what carb you are using but maybe it would work for a Qjet
 
I had a small issue with heat in the carb. I made a plate under the carb with all the clearances for the linkage, etc. and used two gaskets. Seems to be OK now. Oh, I made the plate out of 7075 T-6 aluminum. Just a scrap that was in the bin to recycle. I think it was about 14" square to start. I cut, drilled, and rolled the left and right edges to clear as nessasary. I can post a pic, when I get my computer at home fixed.

Tank

Yea, yea, I know somebody is gonna call me out 'cause I do aircraft sheetmetal every day.:blush:
 
GM has one of these and I think Holley sells one too. The dark gasket in this picture is 1/4" thick, the plate is just aluminum. Aluminum dissipates heat/cold pretty fast so I'm thinking it's a good choice. Ol' Red's had one for years.

234a666a7ad8ee0.jpg
 
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You can probably find Garolite sheet in that thickness. That is the modern (well 50 years ago it was) replacement for Phenolic.
 
Once I get a couple other things done, I'm going to try to figure out where I can find some of these insulating materials.
I don't have a good feel for how much of the heat that's transferred to the carb is by radiation, and how much is by conduction. I'm thinking I might substitute stainless steel studs in place of the present steel carb studs. Stainless steel has about three times the thermal resistance as carbon steel. The new studs and the insulator ought to slow down the heat transfer. Perhaps I could also make the insulator longer so that it also doubles as a shield between the fuel bowls and the manifold.

Just thinking.
 
Once I get a couple other things done, I'm going to try to figure out where I can find some of these insulating materials.
I don't have a good feel for how much of the heat that's transferred to the carb is by radiation, and how much is by conduction. I'm thinking I might substitute stainless steel studs in place of the present steel carb studs. Stainless steel has about three times the thermal resistance as carbon steel. The new studs and the insulator ought to slow down the heat transfer. Perhaps I could also make the insulator longer so that it also doubles as a shield between the fuel bowls and the manifold.

Just thinking.

The stainless heat shield is very thin...maybe a 1/16. Why not go with the heat insulator, and the shield? Too thick maybe?
 
Welcome to the motley crew of the Flying Dutchmen.....

It looks like you have a spider type intake there, no crossover, just setting in air, like the old Pontiacs used to be....

much surprised you have any kind of heat problem in Sweden....

Florida, is 100f in the shade.....:hissyfit:
 
Welcome to the motley crew of the Flying Dutchmen.....

It looks like you have a spider type intake there, no crossover, just setting in air, like the old Pontiacs used to be....

much surprised you have any kind of heat problem in Sweden....

Florida, is 100f in the shade.....:hissyfit:

I dont have any heat issues!,cool carb=more power;)it´s a significant difference in carburetor temp now!,its a Dart air-gap manifold.
 
Hi!,i run the holley carb heat-shield and a phenolic spacer on my 427sb,it works really great!thum_6964a673cf386701.jpg

Welcome!

Areyou using gaskets areound the heat shield?

Thanks,not really sure what you mean with gasket areound the heat shield?.

Should be on both sides....but I have to laugh, land colder than Minnesota even, rivals Alaska.....and you worried over heat on a carb....SOME days it would be nice to breathe air like you got, I say that NOW, come December it's my turn to laugh....:hissyfit::smash:
 
Hi!,i run the holley carb heat-shield and a phenolic spacer on my 427sb,it works really great!thum_6964a673cf386701.jpg

Welcome!

Areyou using gaskets areound the heat shield?

Thanks,not really sure what you mean with gasket areound the heat shield?.

Should be on both sides....but I have to laugh, land colder than Minnesota even, rivals Alaska.....and you worried over heat on a carb....SOME days it would be nice to breathe air like you got, I say that NOW, come December it's my turn to laugh....:hissyfit::smash:
Two weeks ago i had a long trip,3hours drive,it was 31degrees celsius that day:quote:
 
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