Filtering Ram Air

[jim miller]

Is there any way to filter ram air on the older RV3's (Kit from 1984). The
carb heat air is filtered but not the ram air which is used 99% of the time.
I may be worried about nothing but can't grass, dirt, bugs be a problem? I
don't want to mod the cowling and as I haven't hung my 0235 yet have no
feel for what kind of room I will have to work with to try and mod the old,
tiny fiberglass carb heat box which filters only carb heat air.

Thanks
Jim Miller

 

[smokyray]

Clean Air up there...

Is there any way to filter ram air on the older RV3's (Kit from 1984).
Thanks
Jim Miller

Hi Jim,

I built my RV4 pre-FAB days as well. The early RV-4 builders manual had a nifty drawing of a RAM-Air/Filter bypass in it. I modified it slightly and installed it on my RV4 in 1995. It's still flying and working well 1500 hours later. Simply put, it's RAM-air inflight and filtered on the ground by pulling a carb heat knob. It also doubles as Alt-air and carb heat as the metal top gets hot being close to the sump and worked well the one time I needed it. You can build it out of .040 with a K&N 2" flange 6" filter right off the K&N website. Email me offline if you have any questions.

Here are 2 photos.

V/R
Smokey
[email protected]

 

[jim miller]

Smokey Ray
Thanks for posting the photo's. I saw another RV3 like mine this weekend
and it had been modified similar to your photo's. I will do same thing and
like you suggested use carb heat when on the ground where the liklehood
of dirty air is greater.

Thanks
Jim Miller

 

[jrs14855]

carb heat

Nothing wrong with using "carb heat" for takeoff with this setup. This is really not a true carb heat setup but kind of halfway between carb heat and alternate air. The old Luscombe 8A with a fuselage tank required carb heat for takeoff. This on a 65 hp airplane that barely made it into the air with everything working right.