T

tomagin

Active Member
Have been doing the FWF installation on my -8.

I have a new XI0-360M1B with the Van's FWF kit that includes the heat muff and exhaust from Vetterman.

I installed everything per the instructions which include installing the heat muff on the #1 cyl exhaust pipe.

Now that I am doing the baffles I see that the "vent" which I assume supplies air to the heat muff is behind the #3 cyl and you can't easily plumb it the heat muff on #1. The instructions say the heater muff should be connected to the inlet on the cooling ramp in front of the #1 cyl but there is no hole for this and I'm not sure about the space.

There is a bit less room but I'm not thinking of putting it on the #3 cyl but the directions of the inlet/outlet still don't look right --- although workable.

There is plenty of length on the #4 but the crossover leave no space to install it. The pipes come within less than half an inch so I can't really be installed there --- despite the eccentric flanges on each end.

What have others done?
 
tomagin said:
.....a new XI0-360M1B with the Van's FWF kit that includes the heat muff and exhaust from Vetterman......What have others done?
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Tom,

I installed it per plans. It is not a very elegant solution and I'm sure others have come up with a better way. The scat tube run is long. It seemed no matter how I oriented the heat muff, the scat either rubbed on the lower cowl or touched an exhaust pipe. To ease clearance problems I added an elbow to the muff and installed two heat shields on the exhaust pipe to help protect the scat. You must locate and open an inlet hole in the right inlet ramp per plans. In my case, I only opened that hole to 1" dia. I figure I can always increase the hole diameter later if I have too.

 
Tom...

For reasons unknown we have 2 heat muffs ... We got standard Van's FWF kit, and Finish kit, but still no idea why 2 muffs :confused:

The "inlet" to the muff is indeed ahead of #1 in the baffle kit (as Rick). Our muff output goes inside the #1 intake pipe, but then outside #3 and round to the vent on the firewall. That is with the new XP-IO-360 sump. With the earlier plastic one it went inside #3 intake as well...

Compared to Rick's photos, I reckon our muff inlet/output are @180degrees out - his seem a lot less?

Andy (Hill)
RV-8 G-HILZ
 
I missed this in the plans. It's not on the baffle plans... must be on another set I didn't look at.

OK, I can add an inlet at the front easy enough. So the vent behind #3 is just that.... a vent to add some fresh air to the area behind the engine and baffles? Pull some air around the back of the number 3 cylinder? I suppose it is no less air than is going through the oil cooler on the other side.

As I was sent 2 vents with the same part number I suppose one is for the front inlet ramp. I'll chase up the correct drawing and see.

Looks like I'll have to find a way to keep the SCAT from rubbing against the exhaust as well.

Thanks for your input. Obviously both of you thought the installation was a bit strange as well but you read the plans in a bit more detail than I.
 
Like Andy, I too received a pair of heat muffs. One was included with the FWF kit and one was included in the Vetterman exhaust system. I tend to believe that Van's has a slight "inventory control" problem here. I sent the FWF heat muff back for a refund. It has a list price of $118 and I received only $106.20 because of the 10% restocking fee. Add my cost for shipping it back in the first place and I received even less. Go figure.

As regards the vent behind the #3 cylinder, you are dealing with a new and improved baffle kit. It is major improvement over the old baffle kit but since the baffle kit is designed for several applications, it is in a sense generic in nature. That vent behind cylinder #3 is used with some engine installations but not with ours. For instance, that vent IS used in my 0-320 setup. Since this FWF is built per Van's DWGS and I could find no documentation to account for the vent in this application, I simply plugged it.

Another thing about the new baffle kit: Review the link to the problems I had in adapting it for use in the RV-8. It became apparent that something was not right when I first tried to install the baffle mounted oil cooler. I ended up scrapping 3 baffle pieces before I got it right. The pictures I provided during the discussion should give you a good idea of what to expect.

http://www.vansairforce.com/community/showthread.php?t=22322

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Would be nice if the new improved baffle kit had better instructions as far as this vent goes. I have been following the set of instructions that came with the baffle kit and not really looking at other plans. Since the rear baffle behind #3 has the hole already cut and it appears on the instructions I assumed it was part of the program. There is no hole precut for the cabin heat intake.

I don't know how the older baffle kits were but I am impressed with the fit on this one. It is well made and looks like it will seal very well.

I have already installed the oil cooler in the rear left baffle with no issues other than Van didn't apparently send me the -3 nutplates that hold it on. I'll consider the theory of putting in a spacer to move it back a bit to improve the flow.

I guess I'll drill out the vent behind #3 and put a plate over the hole. Although I keep thinking if I can work that vent into the heater system --- perhaps by putting the muff on #3 I would have slightly warm air off the cylinders as the initial feed into the muff instead of ice cold air at the front.

I'll ponder this a bit more. What's the vent for in the O-320 installation?
 
Any updates on this? Is anyone using the outlet behind #3 for the supply air for the heat muff? I am working on an 8 with superior vertical injection, trying to make a heater that works.
 
Not much help but,

I used the #3 air supply location and had a muff made to put on #3 exhaust pipe. Worked out very well as far as a nice tidy installation. It is a shorter muff and is OK for California. Don't think it would be so good in colder climates.

I could use more heat in the cabin for those colder times. I'm thinking of adding a second muff in series with this one as seen on another thread.

Will post a picture a little later.

Ted

ry3D400.jpg
 
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I did it on my 6

Behind number three is a better choice, heated air, shorter scat run. Also block half or more of the outlet off to increase the heat transfer, this per the heat muff expert Rick Robbins of VAF supporter Robbins Wing. He told me they have tested a lot of different ideas and configurations and the combination of those two things; locating outlet behind #3 and partially blocking it to lower the air volume gave the best results.

Hans
 
Thanks for the quick replies, I think I will give the #3 location a try. So is the 1" hole size the best compromise with the 2" scat?

Thanks, I will be needing good heat, it seems to get cold here in North Dakota!!

Lance
 
lancef53 said:
Thanks for the quick replies, I think I will give the #3 location a try. So is the 1" hole size the best compromise with the 2" scat?

Thanks, I will be needing good heat, it seems to get cold here in North Dakota!!

Lance
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I have a 3/4 inch hole with 1 1/2 inch scat. Heat output is very good with this setup and the smaller scat makes routing the tubing much easier.
 
Heat Muff on #3

Hi there,

I also pondered the muff on #3 as the baffle had a designed-in vent outlet right there. I fitted the muff and it works out OK. The ends ride the exhaust bends slightly, but on the negative side the inlet and outlet dont end up pointing in good directions (mentioned above). I did speak to Rick Robbins (Robbins Wings Inc.) and have purchased a 9" shroud with inlet and outlet in same direction. This should work out well.

From a safety perspective, is it better to pull air ahead of the cylinders?

By the way, if that vent on #3 was not for the muff - what is it for?

Cheers,

Robert Grigson
RV-8 Fastback - IO-375 M1B
 
lancef53 said:
Thanks for the quick replies, I think I will give the #3 location a try. So is the 1" hole size the best compromise with the 2" scat?

Thanks, I will be needing good heat, it seems to get cold here in North Dakota!!

Lance
Click to expand...

Think electric seats. The heat from the engine is enough for the toes only!

Hans
 
Off #3

I also moved my muff to #3. The original muff that came with my Vetterman exhaust didn't really fit very well there so I sent off for one that was an inch shorter. Much better fit.

Michael Wynn
RV 8 FWF
San Ramon, CA
 
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