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Air filter in Sam James Cowl

pa38112

pa38112

Well Known Member
I have a 6A with a Sam James cowl. When installing the bottom half of the cow, the air filter housing slips over the ram air inlet in the cow, but is only held in place by the flex hose between it and the carberator. I find that in flight the force of the ram air pushes the filter housing back so that it slips off of it's perch. Has anyone with a Sam James cow solved this problem and if so, how ?
 
Possible fixes

How about building a fiberglass shoulder around the OD of the induction tubes so the flexible coupler can't push farther on to either side of the joint?

Also, for the rear connection, I was able to find a robust silicone induction coupler from an automotive application that fit perfectly. I don't remember the size or the source, but you can find lots of suppliers on the Internet. You can even find instructions on making custom DIY silicone couplers.

M
 
Hi Keith,

I found some reinforced truck hydraulic line that was the exact fit to the aft flange on the cowl inlet nozzle. It was a snug friction fit but provided a robust connection between the back nozzle flange of the cowl inlet and the conical filter box. At the filter housing to carb end I used the double thickness (SCEET?) silicone tubing which has the smoother interior vs the exposed wire. I also suspended the filter housing via the aft circumference flange on the filter housing to an alternator bracket bolt with one of Larry Vetterman's tube and hose systems. It takes the wt of the filter housing off the hose connectors but lets the aft end of the filter housing move with the engine while the hydraulic line holds the front end in place.

Of course none of this would work to resolve the problem Steve mentioned.

Hope this helps.

Cheers,

db
 
My air filter housing is also suspended using the Vetterman hose and tube approach like Dave mentioned. They're stiff enough that the AF housing does not migrate aftwards during flight. Hmmm ... maybe after a couple hunnert hours that will change .... :(
 
db1yg said:
At the filter housing to carb end I used the double thickness (SCEET?) silicone tubing which has the smoother interior vs the exposed wire.
Click to expand...

I seem to recall somebody sucking the fabric liner and having a power interruption.

Might want to look at solid silicone hose sections. They're available all over the net.

2z89kzd.jpg
 
DanH said:
I seem to recall somebody sucking the fabric liner and having a power interruption.

Might want to look at solid silicone hose sections. They're available all over the net.

2z89kzd.jpg
Click to expand...

Dan,
Nice setup.

If I am thinking right.
Expansion chamber for ram air= more volume.:rolleyes:
Just looking at the pick.



Boomer
 
Bruce said:
Dan, Nice setup.
Click to expand...

Hi Boomer....no, not really. Structurally speaking (the OP's interest is mounting method) it is fine. As a low restriction filter system it sucks. The cone filter doesn't have enough media area.

This is the good one; measured restriction is lower than a popular unfiltered intake. Same mount method. It just hangs between two reinforced solid silicone hose sections:

2n6vggx.jpg
 
More info please

Dan,
I respect your work!
Great timing, as I 'm installing a James cowling/plenum and induction system on a -6, 0-360 A1A. I'm almost done with cowling and plenum and about ready to start on induction, obviously I'm doing this to improve looks and performance, so your comments about the cone airfilter caught my attention. Can you explain your "unit" in the picture and any details like part numbers and if you "made" the unit, etc....Thanks in advance.....and if this info is in the archives, just point to it....TKS
 
Dan - very clean custom rig you have there. How do you keep the air box from beating the sides of the scoop during the infamous lycoming dog shake on start and shut down?

DanH said:
Hi Boomer....no, not really. Structurally speaking (the OP's interest is mounting method) it is fine. As a low restriction filter system it sucks. The cone filter doesn't have enough media area.

This is the good one; measured restriction is lower than a popular unfiltered intake. Same mount method. It just hangs between two reinforced solid silicone hose sections:

2n6vggx.jpg
Click to expand...
 
Is this feasible for yours?

This is not mine but very similar. The conical housing holds a K&N filter from a big Ford engine. This is just by the book from the instructions that came with my SJ kit.
This link should be "public". Let me know if it does not work for you.

http://sdrv.ms/130nDgi

Perhaps yours is different, but I don't understand the floating part. I have neoprene between the front end and cowl, but the rest is self supporting as pictured.
 
filter media

Hey Dan,
care to share your filter flow testing results? I'm looking for pressure drop and the flow rate you tested.

what diameter inlet did you use and why did you select it? It looks like a bit bigger diameter than would be required for 390 cu in at 2700 rpm.

It also looks like the assembly is too short to use the 7 degree angle for recovery. Is that why the inlet is a bit bigger?

absolutely awsome work.
 
NDrv8r said:
Hey Dan,
care to share your filter flow testing results? I'm looking for pressure drop and the flow rate you tested.
Click to expand...

Don Rivera was kind enough to run it on the Airflow Performance bench with a FM 200 throttle body and an inlet bell. If I recall correctly he selected 1400 PPH as a full throttle baseline air requirement for my IO-390.

http://www.vansairforce.com/community/showpost.php?p=370492&postcount=9

what diameter inlet did you use and why did you select it? It looks like a bit bigger diameter than would be required for 390 cu in at 2700 rpm.
Click to expand...

The combustion air inlet is no different from the cooling air inlets. You can convert dynamic pressure to static pressure with internal diffusion or external diffusion, or something which suggests indecision ;) This one is external diffusion, and thus the internal ramp angles shouldn't matter much. However, yes, the larger inlet diameter minimizes divergent angles to the big filter.
 
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