I’ve been on the road the last couple of weeks, and I haven’t exactly been wonderful about updates, so let me give you the big picture. After fiddling around with various combinations of throttle body configurations, I figured out that the way the AFP manual states, with the TB clocked 90 degrees and the arms on the bottom, is the way it’s going to be. This will let me get the mixture cable on a straight run across the bottom of the sump and the throttle cable in at a 45 from the left side. Interference between cable brackets might be a factor, I’ll have to check, but I think I’ll be OK. The only thing that concerns me is the distance from the #1 exhaust pipe to the throttle body and cable. The plan is to use the heat muff as a shield, which should work, as there will be cold air coming into it constantly and carrying away heat radiated from the pipe. This makes the fit a little tight, and there will be a need to shield the cables as well. Fortunately, there is a plethora of products designed to do this very thing. Now, one thing to be aware of is that the shielding must not interfere with the cable operation, and must be effective enough to keep the cable from being damaged, because damaged cables stick. You do NOT want a stuck fuel system cable. Best case scenario is that it sticks open and you have to regulate power on landing by turning the ignition on and off, a digital engine, so to speak. A worse case than that is that it sticks closed and you basically join the engine-out club. Absolute worst is that it catches on fire and burns and you hit a UFO on the way down, provoking an interstellar war while trying to wrestle a burning aircraft to the ground. This, however, is unlikely. Custom brackets will still need to be made, and I think I can make them either from billet aluminum or schteel, but I might have to draw on my uncle’s machining capability for steel. I can also make them from 1/8″ 4130 sheet, so for the first time in my life, I can honestly say I NEED a plasma cutter.
So with the firewall forward install more or less on hold for now, I went on to installing probes and senders. I got the CHT probes installed, K-type wires spliced, and extensions run back to the RDAC on the firewall. These will need dressing and permanent mounting. Oil temp probe is in, and I got my fitting to go from AN3 to AN4 on the oil pressure line. I also re-clocked the right mag so the harness clears the battery. This was interesting. I got a timing box from Sac Sky Ranch, then timed it according to procedure in the manual. Pull the mags, rotate the engine to 20BTC as marked on the flywheel, insert the timing pin in the mag, reinstall. Then connect the timing box and turn the other mag so the lights both go on at the same time. It’s a little more involved than that, but that’s the general ideal.
So with that done, I decided to cut my instrument panel. I cut the hole for the EFIS, which had to be adjusted after someone on VAF mentioned the tube under the glare shield of the canopy. I did the poor-man’s laser technique. Marked it out, masked it off, cut it out with a sabre saw. I’ll post pics when I get a chance. After that, I had to dial in the radio stack. I put all the components on their side with the bezels aligned, then taped them all together. I marked lines on the trays for alignment later, then measured the hole I’d need based on the dimensions of the components minus the trays. Once I got the hole good enough to get all the components in, I lined up the stack to the panel by means of lots of clamps. Then I took the components out of the trays, got out some more clamps, and fastened everything down for drilling. I now have the hole for the stack, the primary angle on either side to hold the stack, and next is the bracket that ties them all together at the back end. I’m going to have to cut the subpanel to account for the GNS430’s massive booty, and the whole thing will be bracketed to the subpanel for extra rigidity.
I also lined up and drilled the holes for the toggle switches above the radio stack. I still need to drill the holes for magneto switches, battery master, and alt e-bus feed to the left of the EFIS, but I need to determine what kind of switchgear I need. I think I’m one switch short, which is puzzling, because I checked my order against my plan several times. I also have to go to Fry’s and pick up some electrical supplies like a warning light and a dimmer for the cockpit lights, but it’s getting to the point where I can start actually wiring things instead of just making wire runs.
I’ll post some pics as soon as I get them off my phone.