Heater bonnet vents

The final step of the heater move, inlets on the bonnet;

My layout has a central pattern to line up with the heater inlet, and two side patterns which are both for aesthetic reasons and to let more engine bay heat out. They will let rain water in but the amount this car drives in the rain - I'm not concerned about it; any ingress will drain directly through over the gearbox to the road.

The layout is 10mm diameter holes, 10mm apart left/right, 15mm apart fore/aft laid out in powerpoint and printed to scale. Template aligned with the heater inlet underneath. Prior to starting I tested hole spacing on a scrap to ensure it didn't weaken the area too much:

3.2mm pilot hole widened to the 6mm required for my sheet metal punch. I carefully drilled them with the bonnet in place on the car - it was the easiest way to hold everything rigid, just needed some care with length of drill bit and awareness of what was underneath:

The sheet metal punch leaves a completely finished hole, no need for filing and a very slight bevel towards the inside of the bonnet:

31 holes, 2 hours work - result as planned though, pretty happy with that:

I just need an opportunity for a drive to see if the heater can still pull in air from the boundary layer around the car when it is moving.

Thats it - the end of the radio/heater project!

Update - short trip round the block today, there is certainly a draw of air through the heater, without the fan going, just using the cars forward speed. The area I have my inlet vents must still be close enough to the windscreen to be in the high pressure area.

Aux Panel re-install with radio & DRL

Wiring: Fusebox

New key for the fuse box, in the process of adding the new circuits I documented all the fuses. Colour coding matches fuses to those which have relays switching them: (My fusebox is upside down vs. standard Zero build, fuses above relays)

Wiring: Savage dimmer

My new preferred Savage switch dimming circuit vs the old one.
The same approach is used on all three switches with the output +ve load looped over to the LED side of the switch. Thus on the fog switch, which takes +ve from dip beam it is a true tel-tale, the switch only lighting when the fog lamp itself is lit.

No extra diodes necessary, the LED itself is a diode so won't let current back through to the side lights circuit when the switch is off and in any event its grounded both sides in this scenario.

Update - this could do with a fuse on the LED ground line, shared between the three switches.
If (when?) the LED/bulb shorts it will blow the fuse on the +ve feed - taking out headlights or sidelights fuse. With a separate very low current fuse on GND any problem with the LED/bulb will leave the primary load circuit working.

When off: 

• +Ve feed connects to nothing
• If side lights are on they illuminate the switch dimmed by the resistor

When on:

•  +Ve feed connects to the load and in parallel through the LED, thus when the load gets power, the LED gets power.
• For the fog lamp the +Ve feed is the dip beam line, so when on  with dips off then the switch LED does not light and neither do the fogs.

The savage LEDs are rated 12v so the resistor is only to dim them slightly, I used 0.6W 5k6 Ohm resistors. The resistor should dissipate approx 0.02W when side lights are on.

Aux Panel MkIII

Final steps on the new version of the aux panel, vinyl covered and an override switch top right so the electric aerial can be indepdendently turned off. My thinking is this will be useful either if it gets stuck, or more likely to ensure I don't raise it in the garage while testing the radio. 

I'm using the original sides of the old panel, the second picture showing how the front face is now a little more vertical:

I still don't have a new push-pull for the heater control in the left most position, so just a placeholder blank plate for now:

 Trying to keep the wiring as consistent and neat as possible & went back to the standard 11 way connector for the panel. Re-used the old earth rivnut for a stand-off to support the back of the radio:

With the heater matrix on the other side of the firewall bulkhead & the aux panel itself sitting slightly more vertical there is a good inch of space between the radio back and heater box:

Testing: Side lights off, then side lights on which illuminates the switches, radio volume button(when its off) or dims the radio display when its on:

The Radio did give me one gotcha - it takes two live feeds, one permanent to maintain its memory/time etc, and one via the ignition to allow it to turn on - I wired up exactly as per the manual using the standard ISO connectors - but it turns out this particular radio needs these two feeds reversed to work properly - go figure :)

Update - after talking to Blaupunkt, turns out the radio when wired as standard will turn on when ignition is off but only for 1 hour. So currently wired to not come on at all - may change it back in the future.

And my nifty (although already temperamental) electric aerial. It works well as an aerial, and I like the way its hidden when not in use, however it also has a habit of not quite winding all the way down - I'll pull it apart and re-grease/clean etc at some point:

Daytime Running Lights

The DRLs wiring installed now, switchable via the aux panel. I bought a switching box which takes +Ve, Ground and a feed from the side lights to automatically turn the DRLs off, overriding the panel switch, at night time when the side or headlights are turned on. The 6 lights just below the headlights actually look brighter than this in bright daylight - very pleased with the effect.

More noticeable in these later examples; my Zero is in the far distance on the first with only DRLs on:

Took her out for a test drive to Ashford on the M20 and back on the A20 ... :)

Passed a couple of huge articulated lorries near Maidstone, a matt black Pirelli & a Grey/Silver one possibly Mercedes, presumably on their way from the Silverstone F1 Grand Prix today heading to mainland Europe.

The radio is much clearer, no distortion now at high volume - but still really only useful when waiting in traffic or moving under 50mph, after that buffeting takes over and all you can hear is wind - I'll add in a headphone circuit later.

Over 50mph there is more to concentrate on anyway!

Final part of the upgrades is the holes in the bonnet to let air into the heater matrix. I need to be in a calm mood for that one - no second chances.