Project car - 1989 75 3.0 V6 [Updated 12 November 2021]

[jazig.k]

(8" door woofers + 3" wideband drivers (mid-tweeter))

Keen to see you fit 8" in the door! I was measuring and eye balling up my 8" mid woofers to see where they would fit and how much custom needs to happen... I put them back into the cupboard. I'm not keen enough to make a new door panel.

[shiny_car]

Yes, so am I! I don't think the magnet/motor will end up 'within' the door cavity, if it's mounted in the convention 'bottom front corner' of each door (and definitely not the stupid factory position!). As such, it will require a decent 'build out', and need to be done cleverly to look integrated and factory. But hey, that's a challenge I look forward to.

[GTVeloce]

That makes far more sense. However, I still don't quite get your speaker wiring placement. Wouldn't you just run the door wiring straight to the boot in preparation for the amp? And the run a pair of RCA cables and a trigger cable from the head unit back as well? Like I said before, maybe I am getting ahead of myself and you are in the process of doing that shortly.

I installed my amps and sub in a custom made enclosure that went where the rear seats would normally have gone in my GTV. Helped keep the weight central and low plus gave me more storage room behind the front seats whilst retaining the full boot space. Just so long as you don't want to carry any more than two people...

[shiny_car]

That makes far more sense. However, I still don't quite get your speaker wiring placement.

My photos may be a little confusing. 

A 4-channel amp will be in the boot: 2 channels for the woofers, 2 channels for the wideband drivers. The speaker wire I've installed does go to the boot: door cavity to boot + footwell area to boot (2 sets of wire on each side). Another amp will run the sub.

The headunit + processor connect via a proprietary Alpine ('Ai-NET') 8-wire cable, which includes the audio signal instead of RCA cables, and remote trigger wire. The processor will probably end up in the boot, and short RCA cables and remote trigger wires will connect to the amplifiers.

[GTVeloce]

Ah, all is explained. Thanks.

I looked up that processor, the Alpine PXA-H800 digital processor. That is some seriously cool gear! I am very happy with my setup but that looks like it would great fun to play with and am always happy if I can improve my sound quality further. I especially liked the RoadEQ. It kind of sounds like noise cancelling headphone tech which I could definitely do with. I have eliminated most road noise and wind noise through new rubbers and lots of dynamat/dynapad etc but my loud exhaust still comes into the cabin but I am not keen on changing that!

Of course my ideal would be a switchable exhaust where I can change the path via a solenoid but I'm still trying to work out how best to accomplish that (short of just handing a stack of cash to someone else).

[shiny_car]

Sorry for the late update! It's been a busy period, both car and non-car related. But quite a few smaller jobs were completed last month.

One small job involved re-doing the right rear 'G63a' ground point. None of the grounds were bare metal, covered with a thin layer of primer paint. This obviously must have worked, but I prefer bare metal, so after unbolting the wires, the area was sanded back to bare metal. Conductive carbon grease was applied between the metal and the first ground wire. After bolting all the wires back into position, normal grease was applied around the area for protection against corrosion.







I also located the rear window demister ground wire, and removed it from the connection at G63a. The wire was around 1m long, which must contribute some resistance, particularly as the demister draws relatively high current. I will cut it much shorter, and ground the wire under the window; generally, electrical conduction 'via the chassis' (body panels) is lower resistance than 'via a wire'.



The last under-carpet cables were fitted for the car audio system, which will feature an Alpine headunit and CD changer in the dash, and a digital processor in the boot. Alpine 'Ai-NET' cables (a proprietary 8-wire bus cable) connect the headunit and changer to the processor, plus the changer will feature a Toslink fibre optic digital audio connection. I originally planned to install a digital-output headunit too, but when I bench-tested my old one, it was faulty; sadly, such models are discontinued and not readily repairable, so instead I will fit a new Alpine model without digital output.

Two Ai-NET cables and two generic Toslink fibre optic cables (but only installing one).



The cables were fitted under the dash, along the central tunnel, under the rear seat, and into the boot. A small opening in the sound deadening trim under the rear seat was cut to pass the cables.

















I followed the suggestion from Craig's Place to upgrade the rear power window ground wires. These wires pass from the switches (in the console between the front seats) to the ground point behind the dash above the fuse board, G52, making the wires over a metre long. Craig suggested adding wires from the plugs to a nearby point on the chassis. However, I preferred to cut the wires and ground to the chassis nearby; I saw little point in keeping the original wires intact.

I separated the wires from the wiring loom and unclipped them from the closest plug.





The new ground point was via one of the handbrake assembly securing bolts, where I sanded back the paint to bare metal. The ground wires from each window switch were cut shorter, and terminated together with a crimp-on ring terminal, then secured in position by the handbrake assembly bolt.









Next job, installing the electronic speedometer adjuster, a Dakota SGI-5C Universal Signal Interface. This device can alter the electrical signal feeding the speedo, to recalibrate and make the speedo accurate, and particularly useful when gear ratios or wheels/tyres are changed. In my situation, the new 18" wheels/tyres will be significantly larger in overall circumference, which would ordinarily result in a speedo reading 'too slow' for the actual speed the car would be travelling.

By fitting the SGI-5C, I can increase the signal feeding the speedo, to make it read faster and match the actual speed of the vehicle. I will eventually calibrate the unit by driving with a GPS unit.



With assistance from Kevin Redden's Alfa Romeo Milano Registry tech article, it was a simple installation. I modified my wiring slightly compared with the article, but the connections were still the same. The basic connections were:
1. +12V power
2. ground
3. fitting SGI-5C 'in line' along the speedo signal wire

The car's Jaeger speedo pulse signal amplifier was under the rear seat, left side. A 'speed pulse' originates from the gearbox and feeds into Jaeger unit via wires in the black plug. The signal is amplified and sent via a wire in the white plug to the speedo. The 3 wires in the white plug were different colours depending upon whether the wires were coming directly from the Jaeger, or from the car loom. You will notice the signal wire coming out from the Jaeger is white, but after the connection in the white plug, it changes to grey.





To install the SGI-5C, +12V power was tapped from the pink power wire feeding the Jaeger, adding a short branch of red wire, soldered and insulated. The signal wire was cut, and to one end I soldered/insulated white wire, to become the 'signal input' to the SGI-5C. The other end of the signal wire was joined to the 'signal output' terminal on the SGI-5C. Basically, the signal wire was cut, and the SGI-5C now fitted 'in line'. A new black ground wire was connected from the interface to the nearby ground point (G63b 'left rear ground point'; paint sanded back to bare metal).









A detailed photo of the SGI-5C connections. As per the tech article, I used 'OUT 3' and set the switches 1-2-3-4 to ON-OFF-OFF-ON respectively. Once the car is up and running, I will obviously notice if these are correct. The UP-DN buttons are for calibration.



This was my result in renewing the roof lining. Not perfect, but not bad. If the material sags again, I will take it to a professional trimmer next time. It took two attempts; the first resulted in a bad appearance over the 'hump' in the middle. I found this challenging because the material could not stretch sufficiently; perhaps stretchier material is available? After much thought, I covered the hump as below.

I chose a colour darker than the original light grey, and with a fine woven texture rather than 'felt-like'. Though, the felt-style material may be stretchier. The material is lined with a thin foam layer.

I laid the trim on the ground over newspaper. Notice the dark remnants of foam still stuck to the trim after my first failed attempt. Out of the packaging (eBay purchase), the material still had crease marks, but these disappeared once glued into position. A close-up shows the grey foam underside. Kwik Grip spray and liquid contact adhesive were used.









This close-up shows the contours of the central hump.



Rather than a bad result from poorly stretching the 'one piece' material over the hump, I created separate 'side pieces'. First, the main material was sliced both sides of the hump and through the middle, after careful measurement. Then progressively glued in sections, leaving only the hump.











The edges were trimmed neatly (eventually to be hidden behind other roof trims), and folded and glued at the front and rear ends, like the original.









To cover the hump, the two 'flaps' were first cut roughly and glued.





Once glued, the edges were carefully reshaped with a knife, leaving small sections to be patched. Then paper templates were cut to match each side.





The templates were transferred onto new material, and cut to shape. The pieces were cut approximately 5mm bigger around most sides. Then the foam was removed around the oversized edges; the shape of the intact material (with foam) matched the templates.







Masking tape outlined the area for contact adhesive to be applied. The side pieces were then carefully laid in place, with the material edges overlapping the main piece, covering the edge-to-edge joins underneath.





In bright light, the overlapping cloth is obvious though neat, and I hope once fitted into the car above my head, it won't bother me, particularly as the hump will be behind me!





The roof panels had scuff marks. These were filled with bog, sanded, then covered with spray putty.









Finish coat was black Plasti Dip spray paint.



That will do this month! The next update will be due in a couple weeks, and I will show the modified roof panel switches featuring LED backlights.

[GTVeloce]

Good work as always. I recently had a go at doing my own headlining with some success. I tried a slightly different but mostly similar approach. I stripped my old liner off and cleaned up the board. I couldn't find a liner I liked and decided to re-use the old one! So I carefully cleaned it (in the washing machine!) and it came out nicely.

The foam I bought from Clark rubber for peanuts and just cut to shape. Like you I couldn't get the hump right but since this was just the foam that wouldn't be seen I also cut and shaped it around the hump. I glued it down with 3M spray adhesive. It came up well as can be seen from the pic.

Once dry, I then glued the fabric down but I found I could not get the length right. Maybe it had shrunk slightly but it still sited perfectly from side to side, only front to back it seemed about 1.5cm shorter than I wanted. My car is no show car so I decided to deal with the fact it wasn't going to be a perfect job. Once on and installed it looked great and worked well.

Until the first hot day. After the second hot day the glue was useless and had come away - both the foam from the board and the fabric from the foam. So, my method was ok but a much stronger, or better still, a heat resistant glue is needed. I noticed you used a similar spray adhesive but also a brush on adhesive. Does the brush on have better heat resistance?

[shiny_car]

Until the first hot day. After the second hot day the glue was useless and had come away - both the foam from the board and the fabric from the foam. So, my method was ok but a much stronger, or better still, a heat resistant glue is needed. I noticed you used a similar spray adhesive but also a brush on adhesive. Does the brush on have better heat resistance?

Yes, I'm a little worried about heat during summer. I redid the lining in my 155, and it sagged again.

I checked the heat rating on various products that I saw in different stores. The Selleys Kwik Grip in my photo was the highest I found, rated to 130 degrees celsius (both the spray and brushable). I'm a little dubious about the spray, because it's such a fine layer; but spray is necessary for the back of the material because the spreadable/brush-on adhesive would clump and soak too heavily and distort the surface.

I ran out of the original spray, then discovered Selleys changed the product! I couldn't find the same version again, and their new one is only rated to 70 degrees! I only needed to use the new spray on the material over the hump, so hopefully that is adequate. Time will tell.

[GTVeloce]

I just looked up the heat rating on the 3M product and it is only 40C! Live and learn I guess. Now I'm tossing up whether to redo it or just pump a whole pile of staples in it!

[VeeSix]

Great update Richard, why does the 75 have the speedometer amplifier but the 90 does not, are they not the same or very similar systems?

I have not had to redo a headlining as yet but my 75 one is currently a little loose, no centre lump to deal with though in a sunroof version  , I remember 33s having a non felt covered roof lining, nothing to collapse just a nice solid interior roof, it would be good to get to the bottom of this adhesive issue though, what product do the professional installers use? 

[MD]

VeeSix,

Great update Richard, why does the 75 have the speedometer amplifier but the 90 does not, are they not the same or very similar systems?

Maybe this photo will clarify your question.The differences in the Jaeger sender configurations is probably just a stage of available parts at the time of production but the end signal from either combinations amounts to be the same in the end. Hope that makes sense.

[shiny_car]

Great update Richard, why does the 75 have the speedometer amplifier but the 90 does not, are they not the same or very similar systems?

Maybe this photo will clarify your question.The differences in the Jaeger sender configurations is probably just a stage of available parts at the time of production but the end signal from either combinations amounts to be the same in the end.

Thanks for answering that MD, because I would have had no idea! 

I have not had to redo a headlining as yet but my 75 one is currently a little loose, no centre lump to deal with though in a sunroof version  , I remember 33s having a non felt covered roof lining, nothing to collapse just a nice solid interior roof, it would be good to get to the bottom of this adhesive issue though, what product do the professional installers use? 

The flat headlining in SR cars is a bonus. I read a tech article on the internet for such a car, and it looked very easy.

In the past I've used a contact adhesive bought from VyFab, professional vinyl suppliers, but hey, no longer have that tin and don't recall any specs. From google, a lot of so-called "high temperature" contact adhesives are rated to around 90 deg celsius. It seems to make the discontinued Kwik Grip that I have exceptional, if rated to 130 deg C.

[festy]

In MD's pic, all 3 are reluctor (VR) sensors, #1 and 3 have an amplifier in-built whereas #2 is just the bare sensor so relies on an external amplifier. I see it uses the same circuit board as #3, but without the amplifier components installed.

There's also a 4th type of speed sender that's completely different to these three...
Recently I fitted a Jaeger speed sensor to my Alfetta, I think it was off a 116 Giulietta.
Having only 2 terminals I assumed it was a VR type, but it turned out to actually be a simple reed switch
This type of sensor is obviously not interchangable with the other three.

[shiny_car]

After this update, there may be a gap for several months, due to the Christmas period, and moving house. Finally, I will have proper space and all my tools at-hand again. In the meantime, I need to pack all the parts neatly and safely in preparation for the move. Then load the car onto a trailer for a 30 minute drive down the highway. 

Over the past month, I trialled and fitted LED backlights to the buttons in the roof panels. It's a nice cosmetic upgrade (even if I won't be driving at night very often), with the bonus of lowering power consumption.

I took inspiration from this post on some Taiwanese forums: http://www.alfaclub.com.tw/viewthread.php?tid=36268&extra=page%3D1

These were the switches for the panels, including spares I accumulated. More LEDs will be fitted to the dash switches (and I'll do testing for the dash gauges to see how effective it is).





The original incandescent bulbs and LEDs were a T5 fitment (socket shape). I purchased from eBay, green, white, and red (Italian colours of course!) to experiment with, though only fitted green and white for these switches. The LEDs were for 12V use, prefitted with suitable resistors (ie: green LEDs operate at about 2.1V; white LEDs operate at about 3.4V).



The original bulbs press-fitted into holders that fitted into the back of these switches. Each bulb was covered with a green 'sock' to provide coloured light. Strangely, every bulb in my switches was blown! Of the four or five terminals, two were for powering the bulbs, and the others for the switch function.





LEDs are polarity-sensitive, meaning they only function when inserted the correct orientation: positive power to the anode, and negative to the cathode. They don't fry if reversed; they simply don't work. Either trial-and-error fitment, or look for the anode and fit accordingly (those familiar with LEDs will recognise the anode/cathode). The Alfa wiring diagram and wiring loom determined the polarity for the switch terminals.

Connected to an external power supply, this was the comparison between the original backlight (using an intact bulb from the clock) versus green LED.





This was green versus white LEDs, being tested. I finally chose white LEDs for the push button switches.



These were two different rear power-window lockout switches. The original was shorter. The longer one was a different fitment, but happened to fit into the centre armrest console (below the power mirror switch) where there was a dummy switch/blank. I will use this for another purpose, and show fitment in the future. I don't know what model Alfa it was from, so I am curious to know if someone is familiar with it.





The bulb holder for the longer switch was different. Carefully unclipping the switch face revealed a cylindrical holder which pulled out, and also functioned as the green light filter.







The LED wouldn't fit into the holder but easily fitted directly into the power socket inside the switch. Tested here, and keeping the colour green.





These were the front power window switches. This article at Craig's Place was very helpful in providing additional information and confidence to open and modify.

I levered the guts from the casing using a small jeweller's screwdriver. Inside, under the face, was the green light filter.





The incandescent bulb was soldered to a dedicated positive terminal, and a common ground/negative terminal.





The switch plates were carefully removed, and the circular contact points polished clean.



I tested a 'single white' LED in place of the original. The LED was removed from its plastic T5 case, and you can see the resistor.



I transferred the insulating tubes from the original bulbs to the LED prongs. After some testing, I chose to use double green LEDs for the window switches.





This shows the two green LEDs carefully soldered into position, then tested.





This was the comparison between '1 white' versus '2 green' LEDs which helped decide the final configuration.



Then original versus double green.





A similar upgrade was performed in the rear power window switches.



Here, I carefully unclipped the rocker switch face from the casing, then reassembled to show a different perspective. There was a reasonable amount of space to accommodate the two LEDs.





I tested two modified rear window switches together below.





After the LED upgrades, I refitted switches into the front panel for final testing. The wiring loom was reconnected to each switch, and the power supply connected to the loom. The results are pleasing.









These were the spotlights, for the front and centre roof panels. I replaced the incandescent W5W bulbs with LED versions which were brighter and whiter.









Then, I upgraded the 36mm festoon main cabin light bulbs with LED festoons.











Unfortunately the 12-LED festoons (after researching further, these were determined to be 3538 type SMDs (surface mount diodes)) were not very bright, and a blue-white colour. I then tried CREE festoons. A single CREE festoon was brighter and whiter than the 12-LED versions.







These were 3W CREE versions, and still not quite as bright as the original bulbs. I have found 5W and 10W versions for sale which I will try.







You may have detected in the photos with the CREE festoons, that the roof panel was fitted to the roof trim. The front roof panel with spotlight was first refitted, re-using the star circlips, wiring loom retainers, then reconnecting the wiring loom. I had reference photos to ensure everything was refitted correctly.





The centre roof panel was refitted, re-using the star circlips, wiring loom retainers, then reconnecting the wiring loom.





Now finally the roof trim panel refurbishment was completed.



That's it for now. Have a Merry Christmas everyone. See you after New Year! 

[VeeSix]

Love your work Richard, very in depth, this thread will be a great future resource