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Rod Bower Induction System

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legacy2039

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Hi all! It appears this product is no longer being supported and my reed valves are torn up and getting stuck in the air can chassis intake ports. My question is, can I simply just remove the reed valve or is it worth remaking using another high temp plastic? Is there a measurable performance boost by having the reed valve installed? Thanks in advance!
 

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legacy2039 said:
Hi all! It appears this product is no longer being supported and my reed valves are torn up and getting stuck in the air can chassis intake ports. My question is, can I simply just remove the reed valve or is it worth remaking using another high temp plastic? Is there a measurable performance boost by having the reed valve installed? Thanks in advance!
Click to expand...

He's quit??? I would definitely (I have one on my 10), want to replace the plastic to keep the intake's functionality. It shouldn't be that hard to come up with a replacement material to replicate the original design. If he's "punched out", I'm sorry to hear that.
 
David Howe tells me that Rod is apparently in declining health. I have one example of the very earliest Bower induction which Gene Evans sent me, with the idea that I would re-invent the components to make induction systems. It is a project on my list, and I know of a few folks that would like one if I can get the parts replicated. However, I do not plan to utilize the Reed valve design (see below).

The earliest Bower induction, as well as the one I made for my airplane, does not use the Reed valves. Rod's has a bypass duct that takes air from the ram inlet and bypasses the butterfly valve, putting air into the filter housing. Mine has an alternate air source from the left cooling intake ramp to the filter housing.

If you have the Reed valve type, and your Reed valves are not sealing when you are on ram induction, you are back-flowing through the filter and dumping ram flow into the lower cowl area. Not only will you experience a modest drop in manifold pressure, but you will develop cooling problems because by raising the lower cowl pressure, you reduce the cooling flow through the cylinders, oil cooler, etc.

You could seal up all but one of the Reed valve holes and put a duct on one of them to the left cooling intake ramp. The pressure there is almost as high as the ram pressure, so the back flow through the filter is very small.
 
That’s really to bad to hear that about Rod. Sounds like remaking the reed valve is the easiest option. If you’re aware of what material the valve is made of, would be great to know. I appreciate the insight on cooling and manifold effects without the reed valve. At the moment, I get about 1in increase when the ram air is open and not experiencing any cooling issues.
 
legacy2039 said:
That’s really to bad to hear that about Rod. Sounds like remaking the reed valve is the easiest option. If you’re aware of what material the valve is made of, would be great to know. I appreciate the insight on cooling and manifold effects without the reed valve. At the moment, I get about 1in increase when the ram air is open and not experiencing any cooling issues.
Click to expand...

I experienced similar symptoms in my rv-10 about five years ago. Working with Rod, I replace the material with slightly thicker material. During my last condition inspection, I noticed that they needed replaced again.

I’ve been trying to find my correspondence with Rod to determine the material and thickness I used. I’ve been checking my history with vendors, but their order history doesn’t seem to go that far back. Unfortunately, I’ve not yielded any results yet.
 
scsmith said:
The earliest Bower induction, as well as the one I made for my airplane, does not use the Reed valves. Rod's has a bypass duct that takes air from the ram inlet and bypasses the butterfly valve, putting air into the filter housing.
Click to expand...

...which is far superior to supplying the filter with hot lower cowl air through the reed valves.

You could seal up all but one of the Reed valve holes and put a duct on one of them to the left cooling intake ramp. The pressure there is almost as high as the ram pressure, so the back flow through the filter is very small.
Click to expand...

Even better. I would not be concerned about the theoretical flow from ram inlet, backwards through the filter and up to the left cowl inlet....because I don't think there would be any.

Assume a 360 with a 3" ram inlet, 8500 ft, 175 KTAS, and a VE of 0.875. The pressure rise measured just before the throttle body would be 0.64" Hg, less a small loss due to the open butterfly in the stream. The available dynamic pressure at this altitude and airspeed is 1.13" Hg, so the 0.64" Hg ram rise is 56% of the available freestream dynamic pressure.

My database of upper plenum pressures, as well as the plots in CR3405, say the rise at the upper cowl inlet is always better than 0.6 x available dynamic, in some cases as high as 0.9. It's above 80% for any good inlet with tight baffles or a closed cowl flap.

Of course you gotta ask yourself if all this ducting and butterfly control is worth it, when it's possible to build an airbox with full time filtration loss at less than 2" of water. The open butterfly and can will be close to that, and duct loss plus filter will be more.
 
All good points and I probably would have gone a different path for the air induction solution but this is the config I currently have and my performance is more than acceptable for my mission. The least effort path is my preferred option at the moment, that being replacing the reed valve. I'm an engineer by trade so I do enjoy reading through these comments.
 
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