First thing I did today was install the heater muff on the exhaust for cylinder #1. I have no idea if the clocking of the outlets are right or not, but I just wanted to make sure it would fit.

I then installed the lower cowl to see if the tailpipes need to be moved. Turns out that with this pipe/cowl combo, if you have an inch of gap above the pipes, you have about 1 3/8" below. I've also got them pointed in toward each other a bit and the result is that there's gobs of room all the way around.

Once that was resolved, I trimmed and permanently installed the breather tube to the firewall. I trimmed the bottom parallel to the l/h pipe and terminated it about 1/2" above the pipe. This is all per print, so not a lot to say about it.

I also added a whistle hole about 6" up from the bottom. Vans has no provision for this, but lots of guys install them and it was actually a Cessna AD to add one back in the day. I realize that this vs. a Cessna installation hanging out in the breeze is totally different, but it's cheap insurance.

Next I fabricated the final end pipe for the engine driven fuel pump bypass line and installed it. This took a while because I wanted to make sure it looked decent while not being overly complicated. I suppose I could have just stuck the end of the hose out in the breeze with an adel clamp or two, but this looks a bit more polished.

Finally, I fabricated and installed the sniffle valve drain line. This took some doing. The RV14 plan is auto Frankenstein together a couple of pieces of aluminum pipe with a couple of pieces of fuel line to account for flexing, with one end clamped to an exhaust pipe and the other end adel clamped to the firewall flange. The RV7 solution is a bit basic as well.

I felt like it was kind of chopped up and I really didn't want to have to fabricate a stainless hangar arrangement for the exhaust pipe, so I played around with this for a while and determined that a simple way to accomplish this is with a hose junction right off the sniffle valve to a piece of scrap 3/8" fuel line that sweeps aft between the exhaust pipes.

The aft end is supported by a couple of adel clamps to the lateral exhaust hanger so there is some flex in the assembly via the hose length up front, but the entire this should move with the engine,

So, if we're keeping score, all this stuff goes out through the cowling shovel right now. The tube on the left is the fuel pump bypass drain and is maid from a piece of scrap fuel vent line. The one in the middle is the sniffle valve drain and is made from a piece of scrap fuel line.

FYI- I gave the end of the sniffle valve line a small flare and safety wired the hose clamps holding it together. I don't want that thing coming apart up under there where I wouldn't be able to see it without having the cowl off.

I'm of two minds about ho this ended up; On the one hand, it's a simple and clean installation, but on the other, the more stuff you have in the cowl exhaust, the more it messes up the exit air back there, which leads to drag. I suspect it might be aerodynamically cleaner to have that stuff exit via stubby pipe out the bottom of the firewall lip outside of the shovel area.

I'll ponder this a while. I can change it any time up until paint so it' snot a big deal to fly it this way for a bit.