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Discussion Starter #1
I’m helping a fellow AfaBBer with completing some tasks on his 4 year restoration of a ‘74 GTV. We trailered the car to my garage where I have access to my tools and ‘73 GTV as a handy reference. The focus is on completing the re-wiring of the car, and getting it roadworthy enough to complete a rolling restoration.

However, there are differences between them, such as a SPICA/Weber conversion that leaves me with some questions and desire for recommendations on best path forward. Unfortunately, there aren’t many photos of the car prior to taking the car to bare metal that I can use as a guide to the non-factory changes made to the car under prior ownership.

So, I‘ll start with this question on the fuel system... A new fuel tank was installed so the supply line comes out the top bung hole and there is a vent connection at the top of the filler pipe. Any recommendations on how to vent the tank? The SPICA vapor recovery tank is long gone, along with the tank mounting bracket. I’m inclined to install an inline breather/vent valve on the vent connection like this with tubing routed somewhere beneath the trunk:


Thanks for your help and input.
EC3104DD-33E4-4FCB-9319-46476C351A71.jpeg
 

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there are differences between them, such as a SPICA/Weber conversion that leaves me with some questions... A new fuel tank was installed so the supply line comes out the top bung hole and there is a vent connection at the top of the filler pipe. Any recommendations on how to vent the tank?
Does the replacement tank have a screw-on or a bayonet style cap? The bayonet caps are vented. However, if the tank has a vent port, it probably takes the un-vented, screw-on cap. So sure, that Merlin Motorsports thingamabob could be connected to the vent port.

But your friend could also take the cowboy approach of blocking off the port and drilling a small hole in the cap. Your friend was already on Greta Thunberg's sh*t list once he installed those Webers!
 

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Discussion Starter #3
The tank has a screw-on, unvented cap. I could always use the plastic vacuum breaker on the vent port that was standard equipment on the SPICA cars, but that wouldn’t address pressure issues.

Any thoughts on electric pump and filter placement? The guy working on the car mounted the pump vertically right above the axle on the tank side. Of course, he didn’t realize the rear sway bar link will hit the pump when the car goes over a good road bump.

The plan is to put the pump in the same location as the SPICA electric fuel pump, tucked up above the left side of the axle. I’d like to mount the filter in the existing bracket as well, but the tank outlet isn’t on the bottom of the tank anymore. Thoughts on connecting the filter on the pump suction or discharge? The SPICA set up is on the suction, but filters are typically connected on the discharge side of the pump.
 

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A friend has a Spica Spider converted to Webers, using a low pressure pump in the original pump's location just as you are describing. A few years back he had to get a new tank, and Spica tanks are NLA. He installed a Euro tank without the bottom pickup. He has a line coming from the fuel level sender, going through the trunk floor to the pump, and the pump never had suction problems. It is an Airtex pump with a small inlet strainer (1/8 NPT pump side, 5/16 bib inlet side) which has a Ford part number.

The main filter is a typical online filter near the carbs.

Jay, I have just checked a bayonet cap I have from a Spica car, and it is not vented. This probably explains why these things had a colored dot sticker on, to differentiate two versions.

The Newton valve is interesting, as it will both allow air to be sucked in easily as you are driving along, will retain vapors to a degree but will vent the tank at some point as vapor pressure builds up under the sun on a hot day.
 

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Discussion Starter #5 (Edited)
The Newton valve is on order...

The wiring is coming along well and should be ready for check out in a few days. We decided to add relays for both high and low beam lighting circuits requiring a new lighting wire harness.

C9441D0D-B6D5-49B6-BE4E-4B9DB5C8DB86.jpeg 2AF8CCCF-4252-4BDE-B03A-256FE080059E.jpeg

Removing the ‘74 US spec seat belt interlock system greatly reduces the wiring requirements. The old harness must weigh twice as much as the Euro spec harness that is available from Classic Alfa. However, if anyone decides to use this harness, you’ll need to add wiring for the fog lights, brake fluid level switch and pressure sender, rear window defroster and interior courtesy and center console lights as well as wiring to/from the small auxiliary fuse box for fuses 11 (fog lights) and 12 (fuel pump).
 

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It would be interesting to have a schematic of your headlamp relay harness with dimensions.
How is the red feed connecte? I see sort of a junction near the battery post but it doesn't seem to connect with the post.
Will you install a third relay for the foglamps?
I've meant to do this for a while, but I want int to be as unobtrusive as possible.
 

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Discussion Starter #7
It would be interesting to have a schematic of your headlamp relay harness with dimensions.
How is the red feed connecte? I see sort of a junction near the battery post but it doesn't seem to connect with the post.
Will you install a third relay for the foglamps?
I've meant to do this for a while, but I want int to be as unobtrusive as possible.
Head Lamp Relays... I wanted to keep it a simple plug and play without hacking into or cutting up the harness from Classic Alfa. The high beam relay is on the farleft and low beam relay is adjacent to its right. The relay trip wire contact (87) comes from the existing bulb connector on the driver‘s side with 16 ga wire; the ground (30j is connected to the horn (black) relay mounting screw. The power comes from the (+) battery terminal where there is an integral black 12 ga wire at the terminal post connector. One of the 12ga red wires comes from the alternator and the other is a 12ga lead to the low beam relay contact (85). The power to the high beam relay piggy backs off the low beam contact. Power to the lights requires two wires (12ga) off each relay contact (86), one for each bulb.The relays have provisions to protect the power circuit with fuses (15a).

Fog Lamp Relay... used the existing relay shown on the far right of the photo. Since the inner lamps remain fog lights, they need to switch off when the high beams come on, so we reused the existing relay. Remember, this is a US spec car so the original wiring for the inner lamps requires this. However, if you wanted additional driving lights, you’ll want to decide what circuit(s) will trip the relay (on and/or off).
 

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Where did you source the headlamp connectors? Auto parts stores seem to think we can only use pigtails.
 

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Discussion Starter #9
I bought a pair of the generic three wire bulb plugs. These cheap things now come with 18ga pigtail leads which had to go. In order to use the 12ga wire with the female connector in the plug, I removed the pigtails from the plastic plug and snipped off the wire, being sure to leave a short stem. I then took a 10ga spade connector, removed the plastic sheathing and snipped off the spade so that I was left with the short metal split sleeve; then inserted the 12ga wire in one end and the stem of the female connector in the other and crippled it; then reinserted it back in the plastic plug.
 

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The Newton valve is on order...

The wiring is coming along well and should be ready for check out in a few days. We decided to add relays for both high and low beam lighting circuits requiring a new lighting wire harness.

View attachment 1648247 View attachment 1648248

Removing the ‘74 US spec seat belt interlock system greatly reduces the wiring requirements. The old harness must weigh twice as much as the Euro spec harness that is available from Classic Alfa. However, if anyone decides to use this harness, you’ll need to add wiring for the fog lights, brake fluid level switch and pressure sender, rear window defroster and interior courtesy and center console lights as well as wiring to/from the small auxiliary fuse box for fuses 11 (fog lights) and 12 (fuel pump).
Where do you find a Newton valve? Tnx
 

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Discussion Starter #12
I've meant to do this for a while, but I want int to be as unobtrusive as possible.
Here’s the finished result keeping things looking as clean as possible. The stock harness is in the normal routing position just under the the top fender line while the new lighting harness is routed below at the level of the battery tray bottom. The relays (L to R) are for high beam, low beam, horn and fog lights.

. F25CC7AF-AF18-46A2-8358-6001809A332E.jpeg
 

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Somebody stole your battery :eek:

Pete
 

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Discussion Starter #14
That’s nothing compared to the interior! Check out the first photo🙂
 

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Curious to know how noisy that fuel pump is. I've recently fired up the one in my car for the first time and was a bit surprised/disappointed at how noisy it is. I'm going to get a rubber vibration damper similar to what you have shown in the photo here and hoping that makes a considerable difference.
 

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Curious to know how noisy that fuel pump is. I've recently fired up the one in my car for the first time and was a bit surprised/disappointed at how noisy it is. I'm going to get a rubber vibration damper similar to what you have shown in the photo here and hoping that makes a considerable difference.
Was it dry of fuel?

Pete
 

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Hi Pete. It has fuel in it, yes.
 
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Discussion Starter #19
Curious to know how noisy that fuel pump is. I've recently fired up the one in my car for the first time and was a bit surprised/disappointed at how noisy it is. I'm going to get a rubber vibration damper similar to what you have shown in the photo here and hoping that makes a considerable difference.
I’ll let you know about relative noise once I fire it up. I’ve got the Bosch pump in the GTV for the SPICA and a pump from Pierce Mfd in the ‘02 to compare it to.
 

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Discussion Starter #20
Curious to know how noisy that fuel pump is. I've recently fired up the one in my car for the first time and was a bit surprised/disappointed at how noisy it is. I'm going to get a rubber vibration damper similar to what you have shown in the photo here and hoping that makes a considerable difference.
The pump is rather quiet. Certainly no louder than the other ps and thats while sitting in a body shell without glass or interior carpets.
 
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