Top Cowling Inlet Ramps Installation ????

[rapid_ascent]

I'm at the point of installing my inlet ramps and I'm little puzzled about how exactly the Inlet Ramps are supposed to be installed. As far as I can tell there are no details on how to do this in the instructions. I understand that the ramps need to be positioned to overlap the forward baffles and outboard side baffles. For the side baffles I think I understand how the baffle seals will lay on the ramp once installed. The problem I have is I don't understand how much to trim to fit the inboard end of the baffles.

I started the process of trimming the baffles for the Inlet ramps and I ran into a problem based on what I have now. I'm not sure if it is an actual problem or if I just need to trim the ramps. I can't quite visualize how the forward baffle seal is supposed to lay on the inlet ramp. At the moment I'm thinking I need to trim the inlet ramps on the inboard side. There is a bump in the center of the top cowling or a recess from the bottom. At the moment my inlet ramps are extending over this recess a little. That results in the ramp hitting the forward baffle in this area. I'm not sure if this normal or simply because I haven't trimmed the inlet ramp.

Some guidance and/or pics would be very helpful.

 

[Roy Thoma]

See DanH's post that may help. https://vansairforce.net/threads/installing-the-“inlet-ducts”.188717/#post-1475755

 

[mburch]

This is going to sound like a joke, but I promise it's not: The best way to understand how the geometry works here is to find a local builder who did a good job on their cowling/baffle installation, and stick your hand into their cowl inlets! It's a hard area to describe or photograph, but if you can touch it with your fingers it becomes much more clear.

 

[blaplante]

There's basically two ways to do it.
Butt the baffle metal/fabric to the ramp, or vice versa.
You've already cut down the metal to fit the ramp, so... plan A (the way I've done it).

1) You may need to extend the ramp outboard to provide a good seal surface for the baffle fabric
2) You *will* need to block airflow from going between the top cowl and the ramp. Otherwise likely air will get into the inboard side of the ramp, flow through, and dump into the area outboard, and from there to the lower cowl. That allows a big air leak. High temp spray foam is an option to fill the hole.

 

[rapid_ascent]

At the moment I'm at the stage where the top cowling doesn't quite fit to the lower cowling. The outer baffles are rough cut to shape and clearing the inlet ramps. The inlet ramps are hitting the outside corners of the aft most portion of the forward baffles, about an inch inboard. I was afraid to cut them down any more at this point since I think this is due to where the inlet ramps are overhanging the recess in the top cowling. Should I trim the inlet ramps back on the inboard sides?