Thursday 25 December 2014

Coil Pack Setup, Engine Bay Completion

To finish the engine bay, I I've had to bundle up my "coil on plug" packs, complete the engine wiring loom, run the throttle cable and run the final radiator and heater hoses.

Regarding the heater, I've decided to go with a VintageAir heater/demister unit as they are so compact and come with their own control panel. I still have the heater box I pulled out of a local 90's Falcon that has all the vacuum flaps to control venting to windscreen/console/floor, etc. I may end up using parts of that as well. When my dash and console are complete, I will have hidden as many controls as possible, as I prefer the "stealth" look personally.

Anyway, here are some photos of the coil-packs. I had to hand-fabricate the coil mounts seeing these are indeed "coil-on-plug" coils which are tricky to securely hold in place as they are meant to sit in their own individual recess in the rocker cover of a 3-valve modular V8. They are approximately rounded, but have a series of tabs and protrusions you need to account for. Ideally, I would CNC machine something up to look the best, but as these items will be almost completely hidden (under the shock tower braces that are temporarily removed just now), I've formed their mounts from sheet aluminium.
At least these two coil packs (one pack of 4 coils on each side of the engine bay) remove the awful looking temporary wooden blocks I've sat on top of each rocker cover for about a year now (and this included the engine dyno session - so they did their job ok). For leads, I've gone with Taylor 9mm "Firepower" items. The 45 degree boots are a very neat fit for my custom extractor setup. Something to note is that with the coil packs being mounted on each side of the engine bay (between the shock-towers and firewall), the spark-plug leads themselves are extremely short, just 6 inches or so for the rear 2 cylinders on each bank. Hopefully I don't need to shift these coils at all later - only to find my cut-back leads need to be replaced.....



















I have used the AN-16 ORB outlets at the rear of each cylinder head to source hot water for my new heater unit. With only limited room in the valley at the back of the engine (because of the oil pressure sender, engine wiring loom, fuel lines, throttle cable hardware, etc - all passing through this area), I have screwed AN-16 ORB block-off plugs into the rear coolant outlets, but I have tapped these plugs to accept brass 5/8th inch right-angle hose fittings. The ORB plugs in conjunction with Teflon tape on the brass fittings - allows me enough "wiggle room" to be able to spin these fittings such they both (1 on each cylinder head) face the firewall and wont leak. It is then pretty simple to drill holes in the firewall to run heater hose from these fittings to the new heater unit. But what I found when I tried to run the heater hose thru the firewall was that my fuel lines got in the way. So I had the re-design my existing "Tri-Y" setup where my 1/2" stainless hard line first split into two 1/2" lines (one for each fuel rail), and then each of these split into two AN-6 lines that feed each end of each fuel rail. All this "splitting" was done at the rear of the valley next to the oil pressure sender and simply cluttered things up too much. My solution was to run the 1/2" hard line right into the middle of the valley and split things up from there. Much neater! Safer too as the stainless hard line is much more resistant to scuffing as the engine vibrates. This photo should explain it better....














A final complication I need to account for is that I can't take advantage of any natural "flow" in my heater hose as I am sourcing heated coolant from the rear of each head (there is no natural "flow" between them). So I need to incorporate an extra heater "circulation pump" - to force coolant through the heater core. I've not built this setup yet, but I will incorporate a "rising rate" switch (using a solid-state relay) on this extra pump so it's not running 100% flat out when only a small amount of flow is needed. I included this kind of setup on my EFI fuel delivery system as it uses twin electric fuel pumps (and there is no point just churning up and heating fuel when idling away while stopped in traffic) - so it's easy enough to do, but is a luxury that can wait for later.

Something else I had to change is the original setup I built for returning hot engine coolant to the radiator. Initially, I had plumbed coolant lines up against the face of the right head (when looking into the engine bay from the front) to line up with the inlet port on the radiator. But the new power-steering and oil filter setup means I have to divert these coolant lines further forward to clear them. You will notice that I've built a new stainless steel "manifold" to join these two coolant outlets from each cylinder head and I've hidden the 3 temp senders (one each for the ECU, water pumps and temp gauge) I require by threading them in from the underside of this manifold.
















This next trick has proved very useful for me. I've installed a "momentary" push-button switch in the engine bay, so I can conveniently crank the engine over when working under the hood, adjusting tappets, etc. Also I've mounted a spare oil-pressure gauge I had off the oil filter housing so I can see the actual oil pressure if I'm working on the motor with the engine running. This gauge provides more peace-of-mind than I expected!
And lastly, I have drilled a 1/2" hole into one of the upper, front engine mounts and welded a I/2" UNF nut on top of it - and into this nut I've threaded a long I/2" UNF bolt. As this bolt faces "for/aft" in the engine bay, when I "tighten up" this bolt and it passes thru the hole, it pushed into the mating lower engine mount and slides the whole engine forward 2 inches or so. This seemed the simplest and easiest way to give me heaps more room to do things like lift the rocker covers, get to spark-plugs, plus access wiring and fuel lines at the rear of the engine. I have to loosen off the front and rear engine mounts for this to occur of course, while the whole exhaust system just rocks forward. Nice.