I secured the crossover fuel line to the engine case:
Crossover fuel line secured to the oil sump
We then started working on the Showplanes intake installation. Because of the small "lip" on the tip of the throttle body, the servo plenum didn't fit immediately. I tried opening some slots on it and that made it go in a bit, but ultimately we just had to lay fiber around it and sand the inside - which also allowed us to set a better angle for it (turning slightly up):
Servo plenum with slots, barely fitting over throttle body
Servo plenum clearing the starter and alternator
Adjusting the position and angle of the servo plenum to add fiberglass to it
Cowling clearance below the servo plenum connected to intake plenum
Servo plenum after adding fiberglass, with a slight angle to it
With that in place, we match-drilled the intake plenum gussets, trimmed them to fit the intake plenums in place, and glassed them together:
Intake plenum gussets attached to baffle ramps
Intake plenum held in place, in alignment
Left intake plenum with gusset trimmed to bring it into the right position
Right intake plenum gusset trimmed to bring intake plenum into the right position
Intake plenums epoxied to their gussets
Last but not least, I added a couple layers of fiberglass to each side of the gussets, fully securing them in place:
Intake plenums with fiberglass securing the gussets
Intake plenum gussets reinforced with fiberglass layers
Next is glassing in the intake plenum caps to the servo plenum, and finishing the top side of the intake plenums by making a smooth ramp with homogeneous gaps to the cowl.
Showplanes now offers a custom baffle kit that fits much more easily with their cowl and intake system, so I got that:
Showplanes baffle kit parts
The main part of the modification is to cut off the ramp part of the stock forward baffle parts, and replace them with the Showplanes-provided ramps (as a separate part that will be riveted together):
Forward baffle assemblies with the ramp replaced by Showplanes'
Left baffle ramp in place
Left baffle ramp and cylinder 2 baffle
Right baffle ramp and forward baffles in place
I had to again remove the governor bracket to get the left forward baffle in, but it fits quite nicely:
Forward baffle in place around governor
All baffles in place
For the EFII tach wire, I opened a slot to get it in, to be held in place with a grommet:
Right forward baffle with tach wire going through it
At this point, after some minor trimming, the forward baffles fit in place and I attached the forward center bracket to the engine case - which required some trimming due to the odd shape of the engine case opening - and match-drilled it into the baffles:
Forward center bracket attached to engine and (temporarily) attached to baffles
Forward center bracket sitting in place, trimmed to fit the engine case opening
We also fabricated the cylinder baffle clips and match-drilled them in place:
Baffle clips
Baffle clips clecoed in place
Finally, I started test fitting the plenum, which will clearly need some work - both to connect it to the cowl air intake openings, and to align (and seal) the oil door opening:
Plenum sitting in place
Plenum oil door opening
One thing we didn't do yet was to bend the forward portion of the cylinder 1/2 baffles, to support the air ramps. We were waiting for the intake system to be sufficiently positioned that we were comfortable taking away the play that the ramps have there - so that'll come next.
I continued the baffles by priming and attaching the aft baffle bracket to the top of the engine case:
Aft baffle bracket secured to the engine
I also trimmed the corner of the right rear baffle to clear the EFII injector:
Rear baffle corner, trimmed to clear the #6 injector
I aligned the Aerosport engine mount cover to the baffle, then drilled attachment holes and nutplate holes on the baffle, carefully positioning those holes so they don't interfere with the engine attachment "ears" behind the baffle:
Drilling engine mount cover attachment holes into rear baffle
Marking position of the left engine mount cover on the baffle
Rear baffle with engine mount cover nutplate holes drilled
The position of the attachment holes is pretty important in this case, to avoid hitting any part of the engine - notably the bottom one, which leaves the nutplate nested inside the engine mounting bracket:
Engine attachment ear structure
Engine mount cover nutplate holes, avoiding the engine attachment ears
Bottom engine mount cover nutplate holes, narrowly avoiding the engine attachment ear's inner structure
It was then time to make the famous baffle mod to increase airflow around the #6 cylinder - I cut off a corner of the rear baffle, and then trimmed and bent a cover to allow air to flow with an offset:
Rear baffle marked for trimming
Baffle mod cover match-drilled to the rear baffle
Baffle mod cover with flanges bent
I then trimmed the bent flanges to roughly fit within that structure, and it'll ultimately be sealed with red RTV.
After some trimming of the rear baffles themselves, I also match-drilled the aft bracket into them, firmly positioning them on the engine:
Aft braffle bracket match-drilled into rear baffles
I then used the clip method to trim the top of the baffles (starting with the aft 4 cylinders and rear baffles, progressively trimming until until cowl both sat at the right height (supported by the Skybolts and our spacers, not by the baffles), and then further until the clips showed a gap of 3/8" from the cowl:
Clips showing the distance from the cowl top edges to the baffles
Clips inside the cowl showing the distance to the rear baffle top edges
Clips inside the cowl showing the distance to the side baffle top edges
The corners required some visual attention too, since the cowl was hitting them first, and some spaces are too narrow for the clips:
Cowl hitting the baffle corner even though the clips show some distance
Last but not least, I couldn't (to my surprise) find spark plug wire seals for the wires to securely go through the baffles, so I designed some (and included a 4th hole in one of them for the EFII temperature sensor) - I initially printed a prototype with MJF (which doesn't tolerate as high temperatures), assuming I'd need to adjust them:
Prototype spark plug wire passthrus, printed with MJF
Of course, since I built a prototype first, there was nothing to fix - so I ordered the final versions printed in Ultem 1010. The Ultem printing doesn't look nearly as nice the MJF, but it's more resistant to heat, so I'll keep it:
Ignition wiring passthru prototypes (top, PA-12 MJF) and final version (bottom, Ultem 1010 FDM)
I managed to make the Ultem look slightly better and flatter by just sanding the surfaces a bit:
Ignition wiring passthrus, before (bottom) and after (top) sanding
Next I'll tackle the forwardmost baffles, which are likely to require at least some customization due to the Showplanes cowl and induction.
Original oil pressure hose, crossing the whole firewall
only to realize that there's no point in running a hose all the way to the other side, only to also run the sensor wire all the way there - so I removed that, and instead got a shorter hose to attach the sensor close by with the Show Planes clamp:
New oil pressure hose, connected to the sensor nearby
We tried to install the breather tube, it then realized the ANL fuse holders should have been maybe an inch higher up on the firewall to not interfere with it, plus the rubber tube clamp would've ended up right against the engine mount, so we instead got a longer (MIL-6000D) hose and trimmed/re-beaded the tube so they connect just above the top Adel clamp.
Breather tube installed in place
Breather hose connected to breather tube, immediately above an engine mount bar
Trimmed and beaded breather tube, along with the hose that will connect to it
Breather hose and tube installed in place
The main downside of this is that it counts on the Adel clamps not allowing that tube to rotate (which was previous assured by the top bend of the tube being connected to the hose), but I guess that's easy enough to inspect, plus the bottom of the tube is not low enough that it could turn backwards (which would create negative pressure and suck a ton of oil out in flight).
I also added a whistle hole, as described in various VAF posts and a Cessna AD:
Whistle hole, to relieve oil pressure if the breather gets iced up
With most of the near-firewall work done, I test-fit the oil cooler (without fully securing bolts or fittings), and realized that the hose lengths I have won't work too well:
Test fitting the oil cooler and hoses, iwth the hoses being too long
Too-long oil hose hitting the heat control cables
I replaced the hose to the outboard fitting with a shorter one, and we reclocked the engine fitting for the inboard one to give it clearance.
The bottom outboard bolt hole on the cooler was also impossible to use with a long bolt - it's just too close to the engine mount - so I trimmed that off as well:
Oil cooler, with two flanges trimmed to clear the engine mount
I also realized that the AN3-40A bolts that came with the oil cooler installation kit may be a tad too long for the bottom holes, as they were hitting the firewall - so they'll be replaced with -37As (for some reason there's no -39A or -38A? but 37A was the right length with one less washer):
Oil cooler bolts hitting the firewall (before even being fully tightened)
With that, we installed the cooler in place, and sealed the sides and corners with Permatex 27038:
Oil cooler installed and sealed in place
Last, we secured the hoses to the engine, engine mount and oil cooler:
Oil cooler with hoses connecting it to the engine
With this, the prescribed part of section FF5 is complete! Later we'll install the oil drain kit.
