1982 GTV renovation

Started by Anth73, May 08, 2020, 03:19:04 PM

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Anth73

#195
Another job ticked off the to-do list was to fit headlight relays, the benefits of which are very well documented on this forum. As expected, my low beams were very feeble in the illumination stakes, whilst my high beams would give a brief flicker and nothing more. I actually thought my column switch was broken and expected to fork out $400 for a replacement. With the relays fitted my high beams work again and low beam now shine brightly enough to make feel confident driving at night.

I ran 12AWG cable from the power terminal on the firewall to a four-way bus bar I sourced from a marine electronics store as it fitted neatly in the space next to the air filter housing and comes with a secure press-on cover. Two SPST 30A relays were used, one for low beam and one for high beam, with 15A fuses fitted to each. 14AWG cable runs from the relays to each of the main plugs behind the headlight buckets but I did not replace the short length of wire from the plug into the headlight itself. The AWG cable ratings are well within recommended max amperage for this size cable and the lengths used, by default I never exceed 80% of the rated maximum value.

The trigger for each relay was taken from the existing main wiring loom. I rewrapped the main loom using a nice cloth tape I picked up from Autobarn and used PVC tubing for all other wiring. Silly me, however, originally snipped the parking light feed wire in the main loom instead of the low beam feed wire. Pays to check twice and cut once!

An added benefit was being able to reposition the main wiring loom as it was routed directly in front of the air filter intake and through the opening in the front panel. It only took a few minutes to unscrew the front grille to get complete access to the wiring loom across the front of the car. I rerouted it to tuck in next to the radiator, including the wiring to the pressure switch on my AC receiver dryer which we located behind the front grille.

I'm very happy with the inconspicious look of the relays and bus bar, plus the improvement in headlight function and safety benefits it brings. Photos attached of the end result, wiring loom and my now clear air filter intake instead of the wiring loom next to it running through the opening.
Now:
2012 Giulietta QV
1982 GTV6 3L fast road build
1966 Giulia Sprint GT Veloce...the long term project
1970 1750 GTV project car for sale

Then:
2002 156 2.5V6 Manual
2012 159 2.4JTDm Sportwagon
1973 2000 GTV with a 1750 rear half...that was a shame!
Alfa 90 (only for its engine mounts)

Anth73

#196
Now that the cooler months are here it was time to address the setup of my cooling fans. The Motec M84 ECU has two fan auxilary outputs that trigger the fans via relays. The fans are twin 13A GATES units within a shroud from an early 2000's Alfa GT 3.2V6 triggered by the Motec ECU. Fan 1 starts at 82C and whenever the A/C is running,  it turns off at 80C. Fan 2 turns on at 86C and off at 85C. Hence you can see that Fan 1 will do most of the cooling with this setup and not take advantage of the cooling capacity of my aluminium radiator and fan shroud.

The Motec fan outputs are not PWM enabled outputs, when the fans start up they are drawing almost 40A each before settling down to about 13A each at full speed. The inrush current cannot be healthly on the alternator and starting up both simulataneously would be a big no-no. So I decided to look into a PWM fan controller that could gradually ramp up the fans to full speed.

There are a few aftermarket options which are pretty expensive, then I found a 20-page long thread on another forum where they used an OEM fan controller fitted to various Mazda, Mitsubishi and Nissan models through the early 2000's. These fan controllers are still available as new factory OEM units (silver in colour) for about $100 or aftermaket (black in colour) for about $40. Either model works on the same design principles, up to two fans are controlled via a PWM control wire. The PWM signal on the control wire can be from an ECU or an existing PWM signal generator. But what sparked my interest is that when this control wire is grounded the fans are no longer powered. If the control wire is left open, the controller goes into fail-safe mode and gradually powers up the fans to maximum speed. Also, if you place a 5.6K or 6.2K resistor between the control wire and ground, the controller powers the fans at around 75%.

I was able to use the fan controller and my two existing Motec auxilary outputs to emulate a two speed, dual fan setup using a 4-pin SPST relay to control power to the fan controller and a 5-pin SPDT relay to control the low-high speed switch by either grounding the control wire (connected to pin 30) via a resistor (connected to ground via pin 87A) or leaving it open (pin 87).

I can now run both fans simulataneously with a 10 second ramp up to full speed with the peace of my that my alternator is not getting smashed. If the resistor fails the fan controller will go into fail safe mode and run the fans at maximum speed when required. As an added safety measure I bought an OEM and aftermarket controller for my spares inventory.

Photos below of the test fitting I did to make sure the fan controller cleared the bonnet, the final setup with all fan controller wiring hidden under the factory wiring loom next to the washer bottle and radiator overflow, the resistor installed next to my power window relays in the passenger footwell (it's grounded via the dash mounting bolt) and the circuit diagram I used to guide my installation.
Now:
2012 Giulietta QV
1982 GTV6 3L fast road build
1966 Giulia Sprint GT Veloce...the long term project
1970 1750 GTV project car for sale

Then:
2002 156 2.5V6 Manual
2012 159 2.4JTDm Sportwagon
1973 2000 GTV with a 1750 rear half...that was a shame!
Alfa 90 (only for its engine mounts)

Anth73

#197
A couple more photos of the fan controller installation. It's about the size of your hand, so quite compact and fits well on the upper radiator support panel. I used stainless steel rivnuts to provide threaded mounts for the stainless steel bolts.

From memory I purchased the sumitomo connectors from Aliexpress. Wiring was 10AWG for the on/off relay given the length of the cable run from the relay to the fan controller. The power and ground wires from the fan controller to the fans are 12AWG. The control wire was 14AWG as I had some spare but you could use 16AWG as it is very low current.

The forum post discussing the PWM fan controller is https://ls1tech.com/forums/forced-induction/1906766-variable-speed-pwm-fan-control-under-25-less-diy.html
Now:
2012 Giulietta QV
1982 GTV6 3L fast road build
1966 Giulia Sprint GT Veloce...the long term project
1970 1750 GTV project car for sale

Then:
2002 156 2.5V6 Manual
2012 159 2.4JTDm Sportwagon
1973 2000 GTV with a 1750 rear half...that was a shame!
Alfa 90 (only for its engine mounts)

GTVeloce

It's a very neat install and likewise the engine bay! I will look at something very similar if not the same soon. I have the Davies Craig electric water pump installed which uses PWM for the pump but sadly not for the fans. The electronic controller just produces a single output which feeds a relay. Your setup will be a much better solution.

Anth73

Hey Julian you may want to look at the Tridon TFS205 dual stage thermo switch to use as the switching circuit along with the fan controller. I had planned to do this when using Bosch Motronic but then decided to go with the Motec ECU and used it to control engine cooling also.
Now:
2012 Giulietta QV
1982 GTV6 3L fast road build
1966 Giulia Sprint GT Veloce...the long term project
1970 1750 GTV project car for sale

Then:
2002 156 2.5V6 Manual
2012 159 2.4JTDm Sportwagon
1973 2000 GTV with a 1750 rear half...that was a shame!
Alfa 90 (only for its engine mounts)

Anth73

#200
In my earlier post regarding the cooling fan controller and relays I also showed how I setup my power window relays on the passenger side. I mounted the driver side power window relays also on the kick panel rather than on the inside of the door frame taking the same approach i.e. using a ground bus bar for all the ground wires which I then ground to the existing under-dash ground point, which is the dash mounting bolt. Power was supplied by a new 12G wire from the existing power terminal on the driver side firewall to a new power terminal on the drivers kick panel. Each relay is individually protected with a 20A fuse.

I allowed plenty of length to feed the wires to the window motor via the curved plastic conduit that will be inserted between the A-pillar and door. Can't remember where I sourced these from but I did find some excellent condition rubber seals for them from the Netherlands, cold climates are kinder on rubber it seems.

The power window motors will be fitted once I drop the car off at Monza Motors for its 1000km service. I was advised these motors are unique to the earlier style doors which have screw-in door cards. Heads will be tightened, fresh oil and filter, plus a few little things to address such as improving air flow to the factory airbox, addressing a vibration in the driveline (think its the front donut cage) and investigating why I get a bit of driveline fore/aft bucking at low speed and light throttle (worn dedion bush?). Meanwhile Paul Rankin will paint my bonnet tea tray, LHS door mirror cover and jack mounting hardware I also sourced from the Netherlands.

Below are photos of the driver side power window relay setup, the wiring schematic I followed (though Pin 85 goes to ground in my setup), the jack mounting hardware I'm getting painted and the power windows motors, conduits and seals.
Now:
2012 Giulietta QV
1982 GTV6 3L fast road build
1966 Giulia Sprint GT Veloce...the long term project
1970 1750 GTV project car for sale

Then:
2002 156 2.5V6 Manual
2012 159 2.4JTDm Sportwagon
1973 2000 GTV with a 1750 rear half...that was a shame!
Alfa 90 (only for its engine mounts)

Anth73

#201
The winter driving hiatus was the perfect time to address a few minor items leftover from the V6 conversion. The job list for Mick and Hugh at Monza Motors consisted of:

- 1000km "run in" engine service
- Airbox mod to improve airflow
- Remove front donut cage and rebalance my shortened Alfa 75 tailshaft to address noticeable vibrations at high revs
- Investigate why the car would kangaroo hop at very low speeds with light throttle openings. This seemed more suspension related than anything to do with fuel or ignition.
- Fit and wire up my power window motors in the doors
- Get my spare keys cut and matched to all door and hatch locks

Rankins Panels were also refreshing the paint on my bonnet tea tray and LHS mirror cover, fit the jack clip and bolt in the boot and the LHS demister clip for the rear window.

The airbox mod is quite straight forward and involves a nice small section of right-angle piping being attached to the bottom of the airbox. This pokes out through the inner guard just behind the headlight assembly. You may recall my dyno power numbers flatlined from 6400rpm to 7500 rpm and I suspected airflow was the issue. I'll give it another run on the dyno once the engine has loosened up a little more to validate if the airbox mod has helped.

The trouble I went to fitting all new wiring and relays for the power windows was justified with a window "up" time of less than three seconds....amazing for a GTV6! As my doors are from the earlier single dash cars they were missing the bump stop for the window. Thankfully I was able to source these from my ever-reliable GTV6 parts man in the Netherlands as he had a couple of rusted out doors which still had the fabricated metal bumps tops with rubber stop in pretty good condition. These were sandblasted, painted and riveted on by Rankins Panels.

My hunch about something in the rear suspension causing the kangaroo hopping was right. It was like a slow motion back and forth pitching movement at low revs in 1st and 2nd gear, like when you're just off idle in slow moving traffic. The existing rubber dedion bush was pretty badly perished and replaced with a new one. We did discuss the merits of a poly bush but the stories of them being very creaky put me off.

Unfortunately we had less success with the tailshaft vibration issue. We removed the front donut cage even though it was confirmed that the tailshaft was balanced with it in place...no improvement unfortunately. We also double checked the whole driveline alignment and fitted some good used factory engine mounts as those I purchased from EB Spares are noticeably taller than factory...a slight improvement but still not great. I've decided to try out an original GTV6 tailshaft which will need to be cleaned up and rebalanced. All my donuts and the centre bearing were new, so I'm not expecting they are a concern.

Below are photos of the airbox mod, the old dedion bush and the window bump stops for the doors. Looking forward to some Spring driving weather and Spettacolo in November.
Now:
2012 Giulietta QV
1982 GTV6 3L fast road build
1966 Giulia Sprint GT Veloce...the long term project
1970 1750 GTV project car for sale

Then:
2002 156 2.5V6 Manual
2012 159 2.4JTDm Sportwagon
1973 2000 GTV with a 1750 rear half...that was a shame!
Alfa 90 (only for its engine mounts)

Anth73

#202
And the airbox mod photos...
Now:
2012 Giulietta QV
1982 GTV6 3L fast road build
1966 Giulia Sprint GT Veloce...the long term project
1970 1750 GTV project car for sale

Then:
2002 156 2.5V6 Manual
2012 159 2.4JTDm Sportwagon
1973 2000 GTV with a 1750 rear half...that was a shame!
Alfa 90 (only for its engine mounts)