Air Filters

[visser]

I want to change the look of my bulky air-filter and cover on my Hatz 1b30, and at the same time wouldn't mind if it got access to air a bit easier.

Does anyone know if a pod, like this: http://www.crc2onlinecatalog.com/pod_filters.htm, would work or could be made to work?

Does anyone with a Hatz 1b30 know the diameter of the air intake on the engine?

[oilburner]

K&N sells all shapes and sizes including pod filters. They can be ordered over the parts counter at Canadian Tire.

Visit the following web page at K&N to pick the shape that suits you.
http://www.knfilters.com/search/universal.aspx

It will amaze you how small the filter would be for your Hatz. The filter for my 950cc Daihatsu is only 3 inches in diameter and 4 1/2 inches long.

Then calculate the air flow in CFM of your engine and pick the correct size filter (and part number!).

There used to be a web page on the K&N site for calculating the correct size filter but I don't see it now. I saved a copy of the web page, excerpt with formula shown below:

Use the formula below to compute the minimum size filter required for your particular application. The usable portion of the filter is called the EFFECTIVE FILTERING AREA which is determined by multiplying the diameter of the filter times Pi (3.1416) times the height of the air filter in inches, then subtracting .75-inch. We subtract .75-inch to compensate for the rubber seals on each end of the element and the filter material near them since very little air flows through this area.
A=(CID X RPM) / 20,839
A = effective filtering area
CID = cubic inch displacement
RPM = revolutions per minute at maximum power
Example: A 350 CID Chevy engine with a horsepower peak at 5,500 rpm.
A=(350 X 5500) / 20,839 = 92.4 square inches

If you are sizing a panel filter, multiply the width of the filter area (not the rubber seal) times its length. If you are sizing a round filter, use the following formula to determine the height of the filter.
H=(A/D*3.14)+0.75
A = effective filtering area
H = height
D = outside diameter of the filter
3.14 = pi
0.75 = the rubber end caps
Example:
H=(92.4 / 12 * 3.14)+0.75 = 3.20 inches

Referencing the K&N catalog shows the proper filter for this application would be an E-1500 which is 3.5 inches tall. Keep in mind, this is the minimum size requirement. To extend the service interval and to provide an even greater volume of air to the engine, install the largest filter that will fit in the space allotted. If the space above the engine is restrictive, perhaps a remote filter arrangement could be used to gain space.

FYI

[nicknick109]

Been looking to improve the airflow on my Hatz RE as and when you find a filter to fit pop a note on the page for me please. Have thought about cutting an old one up and fitting the end bits onto a performance filter. Just an idea.
Nick

[oldbmw]

Whatever filter you use, usually a big airbox will help a lot on a single cylinder engine.

[nicknick109]

To oldbmw,
how the heck do I get a bigger airbox onto the Hatz???
Looking at Stuart's 1B30 he has cut an extra hole in the airbox claiming that a slight improvmet at speed was noticed but tickover was a bit worse. Still all ideas welcomed.

[taildraggin]

I like how Hieko made the intake manifold here:

[oldbmw]

To oldbmw,
how the heck do I get a bigger airbox onto the Hatz???
Looking at Stuart's 1B30 he has cut an extra hole in the airbox claiming that a slight improvmet at speed was noticed but tickover was a bit worse. Still all ideas welcomed.

Run a big volume pipe to a bigger box...The more 'stored ' air there is between the filter element and the inlet valve the better.

[oilburner]

IMHO airbox, filter and intake pipe mods are simply affecting the wavelength of the inlet tract. Since most engines are running at max throttle (3600 rpm??) most of the time, tuning the intake for resonance at that rpm should dramatically improve intake flow, possibly over 100 pct. If you have some time to kill, Google Helmholtz resonator. There are a number of articles on how to use them to tune the intake. Free supercharging