[alpinelakespilot2000]

I have an 0-320, Vetterman exhaust system and Van's FWF kit including the FAB.

In some builders' pictures, I see that the source of carb heat is from an extra muff around the exhaust (at the front of the engine) which is then ducted directly to a flange riveted to the FAB at the carb heat door.

However, neither my Vetterman exhaust system nor my Van's FAB kit make any mention of ducting carb heat to the FAB carb heat door and, additionally, they provide no muff and no ducting flange to do this. Instead, it appears that Van's just uses the ambient heat in the cowl for carb heat.

This leads me to believe that ducting air from the exhaust muff to the carb heat FAB door is a modification others have done to get warmer air to their carb. Is this true?

If so, where does one get the extra muff and are there any drawings anwyhere depicting how the ducting connects to the FAB?

Thanks.

 

[ArVeeNiner]

Robbins Wings

I got mine at a reasonable price from robbinswings.com. Here's a direct link:

http://www.robbinswings.com/Carb_Heat_Muff.htm

 

[flyboy1963]

hotstuff

Steve,FWIW
I'd definitely get the muff from Robbins. I have the Van's snorkel design that clamps to one exhaust pipe .it provides negligible heat.

Note: the Robbins muff has been re-designed so the slot faces back toward the other crossover pipe. check with them for more details.

if you search on this site, you'll find a good bunch of info.
I am just north of you in BC, and other than mid summer, we have potential carb ice weather here a LOT>......even if the Lyc. is not prone to it, I have heard of it happening, and want more heat! I also plan to block off the open sides where the carb air door connects to the inlet pipe. Apparently this is to allow more air so the engine isn't starved......but hey, we are trying to melt ice!...I figure that equates to a loss of power anyway...I want max hot air temp. and volume.

 

[alpinelakespilot2000]

Steve,FWIW
I'd definitely get the muff from Robbins. I have the Van's snorkel design that clamps to one exhaust pipe .it provides negligible heat.

Thanks Perry and Kelly for the heads up on the Robbins system. I'll look into it and make sure I got the most recent or best version.

Dumb me... I asked this question last year but it's been so long that I forgot it. Still good to have the Robbins option though.
http://www.vansairforce.com/community/showthread.php?t=45067&highlight=carb+heat+muff