stack filtration

[twl]

If you have the room, larger is always better for that kind of thing.

[Belgian1979]

Thanks ! For the moment I have other things to deal with.

I'll report back as soon as I can work on this some more.

[Billzilla]

In light of the foam socks being NFG I'm chasing something better.
It needs to be the usual things - small, light, very low restriction.
It'd also need to be a panel type, how about this? http://www.knfilters.com/search/product ... od=KA-7589

[MadBill]

According to K&N's sizing formula: Square inches of filter required for a motor = CID x Maximum RPM / 20839, the model shown on the link (7.4" x 5.7", minus 1/2" W and H to account for flanges) would support a 350" engine to ~ 2,000 RPM...

[digger]

According to K&N's sizing formula: Square inches of filter required for a motor = CID x Maximum RPM / 20839, the model shown on the link (7.4" x 5.7", minus 1/2" W and H to account for flanges) would support a 350" engine to ~ 2,000 RPM...

whats the formula for a cone filter? they have alot more area for the space consumed but i assume the flow is not uniform through the entire surface of a cone

[MadBill]

K&N don't differentiate between the various shapes. A conical filter is technically a 'frustum of a cone'. Here's the math formula: http://mathworld.wolfram.com/ConicalFrustum.html
Note that some have an internal cone as well, which would add a few square inches to the above result.

[digger]

K&N don't differentiate between the various shapes. A conical filter is technically a 'frustum of a cone'. Here's the math formula: http://mathworld.wolfram.com/ConicalFrustum.html
Note that some have an internal cone as well, which would add a few square inches to the above result.

i am aware how to calculate the area but the effective area would be somewhat smaller

[Billzilla]

According to K&N's sizing formula: Square inches of filter required for a motor = CID x Maximum RPM / 20839, the model shown on the link (7.4" x 5.7", minus 1/2" W and H to account for flanges) would support a 350" engine to ~ 2,000 RPM...

Fortunately my engine is 1.3 litres, or ~79 cubic inches.

[MadBill]

K&N don't differentiate between the various shapes. A conical filter is technically a 'frustum of a cone'. Here's the math formula: http://mathworld.wolfram.com/ConicalFrustum.html
Note that some have an internal cone as well, which would add a few square inches to the above result.

i am aware how to calculate the area but the effective area would be somewhat smaller

Instead of burying the formula in the catalog, it would be useful if K&N (and others) just listed the effective area in the specs for each p.n..

[Kevin Johnson]

i am aware how to calculate the area but the effective area would be somewhat smaller

http://www.google.com/patents/US4498915 You might find the discussion by the inventor interesting.

[Belgian1979]

Coming back to this with results : as the engine has been started on the itb's and I've driven around the block for a short test drive a note on the results with the sock filter (unifilter). I put it on before driving around the block. During a startup, it decided to do a little backfire, when I saw smoke coming from under the hood...thought the car was on fire. With a fire extinguisher at hand I opened the hood, no fire but smoke was coming off the socks. Pulled them of in a hurry and threw them on the side.

Meanwhile I have tested a piece of it with a lighter and they do catch fire easily.

I guess I will be looking at an airbox sooner than I thought.

[MadBill]

Who could conceivably have anticipated the possibility of a backfire as they were designing an air filter? Probably the same guy that came up with cellophane ash trays...

[Kevin Johnson]

"There's no product that can't be made cheaper and worse."

[Belgian1979]

I've explored several possibilities in getting some sort of ducting/channel to fit on the stacks that have the bellmouths touching at the interface between 1+3, 5+7, 2+4 and 6+8 and at the same time staying under the hood lines, but not exactly working out.

What about making an airchamber over the valve covers (attached to them) and with a plate that slide over the back of the bellmouth and use some ducting from a pressurized source for cool filtered air. Now I wouldn't be able to get the airbox completly airthight however...
Constructor of the manifold only has metal mesh screen filters. Not good enough filtration, but anything is better than nothing. Maybe a combination of the chamber on the valve cover and that ??

If not, I might have to resort in trying to squeeze some flexible ducting over the stacks and route them over the manifold where I might be able to build a chamber to hold the filter...also a it defying the purpose of the stacks.

[Cubic_Cleveland]

Like you are thinking, I would stick an air cleaner in each wheel well or some place similar and feed this air into a plenum over the valve covers encompassing the trumpets. Do you have much clearance from the trumpets to hood? Might be difficult to keep dry though, depending on your filter placement.