Saturday 23 November 2013

Polyswitch for permanent live

I have an FIA cutoff/kill switch between the battery and the car for security purposes as much as anything. The downside is this means when the FIA cutoff is open no power to the immobiliser 'flashing led' or the radio memory. The option I'm taking is a polyswitch across the FIA cutoff to supply a continuous low current voltage event when the battery is otherwise isolated:

The polyswitch behaves like a self resetting fuse, permitting approx 3A current before it effectively breaks the circuit by heating up and increasing its own resistance. This allows a standby current to virtually everything but prevents the engine being started. Once the polyswitch cools down after a second or so its back to normal. I found one which is rated 16v 3A stable, tripping current 5A.

Functionality is
FIA switch open - (3A max draw) radio memory, immobiliser flashing light works, trips if you try to start the engine.
FIA switch closed - everything functions normally including starting/running the engine.

Fitting
Made up this mini loom and the loops go over either side of the FIA main terminals, the polyswitch itself is the tiny blob which looks like a ceramic capacitor. This ceramic part sits on a small aluminium plate to make sure when it heats up it cannot contact anything else:

Learning
This arrangement is not compatible with a full cutoff circuit that also grounds the alternator via a large resistor. If both the grounding resistor and polyswitch are left in place when the FIA switch is opened (key removed) the grounding resistor draws the tripping current permanently and everything gets very hot. (Learned the hard way - but before any magic smoke was released :)

I'm assuming the FIA switch is a break before make, so no simple way around this - seems you either setup the car with a cutoff that will actually stop the engine & not harm the alternator, or as I have now as an isolator switch which should not be opened when the engine is running.

Update - removed when the fusebox was next open and now these permanent feeds have their own direct fused circuit from the battery.

Friday 22 November 2013

Badges - Fin. "Zero"


To complete the set (Roundels & Flags) some smart Chrome/Enamel metal lettering for the model name:




Its certainly nothing like the standard GBS Model badge, but I prefer it - just retro enough & hopefully will help with the standard  'What is it?' question when people see the car.

The acid test will be how long the letters stay stuck on!

Found online from here: Something Magic


Standard questions so far being:

  • What is it?
  • Is that as fun to drive as it looks?
  • What type of engine, how fast does it go?

Sunday 17 November 2013

GBS Badges

I spent Saturday at the Classic Motor Show & while I was there picked up some pre-ordered badges from the GBS stand. Its a while since I went to the show - and I don't recall it being so massive before - it seems to take over the entire NEC now - not kits but classic cars/bikes/auto-jumble etc. I don't think I saw Lotus or any Sevens other than GBS.

GBS had the white demonstrator and red Mazda based demonstrator on show. GBS Facebook Show page has a picture of the stand, there were a few tens of thousands more people about when I dropped in mid morning:

I'm still not convinced on a nose badge & anyway the bonnet is already sporting Union Flags & don't want to get too busy.

Opted for the steering wheel centre and boot badges:


Custom 'Zero' model badge to come for that space under the GBS roundel later...

Friday 15 November 2013

All change - Headlamps & Indicators

First up some new more discrete indicators, these are designed for motorbikes - the old sitting on the bench for comparison:

Headlamps I've taken a leaf out of various RhoCar examples and fitted some dominator 3.5" lamps. 
Reference shots for the wiring, I managed to keep the same loom just needing to remove and re-install the various plugs.

White - Blue/Red - low beam
Yellow - Blue/White - high beam
Black - Ground

 Comparison - new on the left, old on the right:


All installed and ready to go; I lined up the new lamps by first marking the pattern on the old ones inside the garage door, then without moving the car lining up the new ones. Hopefully thats good enough until MOT:



Took her for a test drive, headlights are fine, almost flush with the top of the bonnet now.
My 5 minute test drive turned into 90 minutes ;) ... down the A229 through Staplehurst, Goudhurst, Cranbrook road towards Tonbridge, hit the A21 then back along the A228 towards Yalding, up the hill and home..  a little nippy, a little wet too !  but good fun.

Indicators are flashing too quickly - so theres something amiss there - I'll have to check the bulb ratings on the new indicators presumably they are lower resistance?

Update - Turns out the original indicator bulbs were 12v 21w,  new bulbs are 12v 10w - so that explains the higher current through the indicator circuit and faster flashing - it must think a bulb is missing - new 21w bulbs on order but I'll check they don't generate too much heat before fitting permanently.

Checked I had no short circuits, left & right hand side seemed to be about the same resistance so picked up a replacement electronic flasher relay too which can switch 0.2-20amps - it doesn't care if the indicator circuits/bulbs are not precisely matched and gives a reliable regular flash. Downside is it won't change rate if a bulb blows.

Update - May 2014 - Although these lights look the part they don't give out a very good beam, noticeably less light than the original 7" reflectors. I'm going to try some extra bright bulbs, but if the issue is with the reflectors then the whole units may have to go.

Sunday 10 November 2013

Radio installed, horn push working, IACV re-wired

The primary change going on was the Radio installation, while I had the aux panel off I also re-wired the switches to show when side lights are on & in the process moved the IACV 12v feed off the Aux Fuse & wired up the steering wheel centre horn push

Steering Wheel Horn Push

This just needed the steering slip ring terminals connecting to the button & Orange loom line connecting to same. The column itself turns out to be grounded so no need for anything else.

IACV

The IACV was working fine but originally I took its 12v permanent feed from the Aux panel circuit. I reconsidered this thinking if the Aux fuse blew due to using the lighter socket etc then I'd lose tick over on the engine too.

IACV 12v feed is now taken from the Alternator switched 12v input (not the battery line, but the fused line to the alternator rectifier.

Aux Wiring

I Re worked the Aux panel wiring as I went, using alternate connectors, these pictures were for reference more than anything else so if I needed to revert to the original configuration I could. I left the crimped spade connectors on the lighting groups - purple, blue, green etc & covered with shrink wrap - theres no point disturbing things that are working fine:

Moving to 3x waterproof connectors with 4 pins each - roughly power on one, switch signals on the  next & stereo speakers on the last. I pulled in a new permanent live feed; Dip beam signal drives the fog lamp, side lights drives the illumination:

Re-assembly

Everything re-assembled & tested:

Night view, as soon as the side lights are on they drive the back lighting on the Aux panel switches as well as the dash clocks:

... and a better demonstration of the brighter lights when depressed (bottom left is the heater fan):


The only pending items now are:

A polyswitch fuse (on order from Ebay) to sit across the FIA isolating switch and provide power to the radio & immobiliser even when its red key is removed. This will let the Radio remember stations and the immobiliser led flash.

A simple high pass filter on the speakers to allow even more volume - depending on my experience using them though.

Revision to the fog lamp button - see post note on the dimmer circuit to work in full tale-tale/indication mode for this lamp to meet MOT regulation.

Sunday 3 November 2013

Aux Panel rewiring - dimming Savage switches

Re working the Aux panel wiring to both install the radio and fully setup the Savage switches so they glow on dip beam. The switches are double pole double throw - one side is used to switch the LED between full 12v and via a 5k resistor from the sidelights circuit.

I picked up the circuit from www.locostbuilders.co.uk, redrawn/coloured for my setup/cable colours. Each switch has its own resistor and separate led feeds from the device itself which should eliminate impact to the cars existing circuits.

This wiring means the lighting indicates when the switch is depressed, not necessarily that the circuit it operates is functioning (there is always a tradeoff)

Key: C - common, NO - normally open, NC - normally closed:

I tried 1k ohm resistors and 5k ohm resistors - the latter used here (but not great pictures) showing the  dim lit state on the left and with the fog lamp depressed on the right - showing brighter when its on: 

The wiring took an age & this is as tidy as I can get it. I'm not using standard automotive colours due to using up some cable I already had but roughly the scheme is:

Red - +ve ignition or permanent (the radio takes a permanent feed to remember stations)
Black - ground
Blue - lights +ve feed
Yellow - device out

All blacks terminated to the casing with a rivnut, and the +ve lines via a chock block:

Losing the light too much to take the dash off and adjust the aux feeder circuit; so the last job today was drilling the M3 cap head speaker bolts & pulling through the speaker cable from the dash area, through the tunnel & up into the boot space:


Post note:
On testing I realised my fog switch illumination was not a true tel-tale - it was wired to the side-lights for its dim and full brightness.

Update - re worked the switches and preferred switch dimming circuit later to ensure the fog lamp is a true tel-tale & standardise the switch wiring.