[RV8RIVETER]

I am fabbing the guts to my intake scoop air filter box for my 11.2 x 5.8 K&N filter and thought I would solicit feedback on an idea.

My filter will slide in/out a slot in the back and am thinking about making a second "racing filter" (Taylor races in my future) out of stainless mesh cloth. Found here,
http://www.bwire.com/stainless_steel_wire_cloth_filter.htm

A human hair is 70 microns, so was thinking of using 60 micron mesh and it should not too difficult to at least double the surface area with proper pleating. Does this sound worth an experiment?

 

[N941WR]

It sounds great but here is the deal, if that filter fails, you are going to suck it right into your engine. And that would, well, it would suck.

 

[elippse]

I am fabbing the guts to my intake scoop air filter box for my 11.2 x 5.8 K&N filter and thought I would solicit feedback on an idea.

Let's say you have a 360 breathing 8,100 cu in/sec through your 65 sq in filter at 2700 rpm. at sea-level. That means that the average velocity of the air through the filter is 10.4 fps, 7 mph. You'll not have any appreciable pressure drop at that low of an average velocity. I have 40 sq in K&N for my O-235, and even at 3000 rpm the average speed through it is only about 9 mph, and I have no measurable drop in my induction system. You may want to put a coarse grid on the cylinder side of the filter to prevent it getting pushed into the carb or throttle valve as somone wrote.

 

[RV8RIVETER]

I am sorry if I did not make it clear that I would be building the filter with appropriate backing, frame, just using the mesh as a coarse media.

Thanks Paul for the math and data point.

I will be measuring the pressure drop across the filter during the test phase, so if that shows a need for improvement I will build one.

 

[DanH]

Wade, Paul is right. Good box shape and plenty of media area will make pressure drop so low that running filterless is a risk for little return.

You know which filter I'm using. For the entire airbox with filter, the measured contribution to intake pressure loss is 1.9" H2O, or 0.14" Hg @1400 PPH flow. Some loss would remain with the filter removed from the box. For scale, it is about 130 feet in altitude, or less than 1 hp. Gotta think carefully about what you're willing to place in the induction path in return for <1hp.

 

[elippse]

As I mentioned in an earlier post, one of the things you need to make sure of in your induction path is that if you have any large turns, make sure the turn is over a radius and not a sharp edge. Sharp edges, such as making the 90?turn from a typical Vans filter box into a carb over the sheet metal, will trip the flow into the venturi and keep it from having a consistent A-F ratio. I used JBWeld to form a smooth radius for the turn.