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I'd like to thank the members here who have been so kind in helping me in my education about the round tail cars.

I hope you might help me with another question that I couldn't really find in the "search".

I'm the kind of guy that likes simpler mechanical things vs more complex or electronic things. So, I tend to gravitate toward Webers rather than fuel injection. In fact fuel injection in old cars scares me. Too mysterious.

But maybe I'm being unfair.

Question: Could someone give me a brief idea about the relative merits/drawbacks of the fuel injection in these cars vs carbs?

Specifically, ease of repair and dependability.

thanks!!! :)
 

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71 Berlina 74 GTV 17 Giulia Q4
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Remember Ron Popeil? Set it...... AND Forget It !!! Spica, then again you get Webers set up and you can pretty much forget them too, as much as you can forget anything on a 30+ year old car. Gas is going to be 5 bucks a gallon in a couple of years and the SPICA will give you the same performance as Webers but cost a hellva lot less gas wise. I had webers and spica on the same engine in my GTV and there was no difference in performance and a big dif in mpg, just my 02
 

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The only FI for the roundtail was on the US '69 model.

Differences include high pressure pump at the tank (this had a lot of problems when new with the pump seizing unexpectedly (suspected due to contamination in the fuel) and the corresponding high pressure fuel return line. Changes to the tank too. Not an easy retrofit to a weber car.

At the same time, the car added dual circuit brake lines with a complex brake system with dual boosters (lots of threads on the troubles in the BB) that also added a rear brake limiting valve.

Webers have a unique sound, especially with enhanced performance in the engine.

Weber Roundtails (66 - 68 euro) are in short supply. Not a lot were made. Tends to be the most desirable model, and priciest for good condition.

Robert
 

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Webers vs. FI

I think you would find that once Webers are set up correctly, they require minimum maintenance. At least that has been my experience on my converted '81.

As noted above they make a great sound, but gas mileage will suffer some if that matters.

Not sure about the Carolinas but here in New England, cold starts after sitting a few days usually take two or three tries to catch, after pumping the gas pedal a few times first. But I don't consider that a big deal, and once started, subsequent starts that day occur with the first twist of the key.

John
 

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I;ve had a '67 Duetto since new, with webers. Updated to a 2L with many mods in 75 - 80, still webers Wasn't hard to find a good jetting, even without the BB to help. Runs fine, no fiddling at all since then (30+ years). Had more trouble with Spica system on an Alfetta (fuel pump and thermostatic actuator).

Robert
 

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Looks like it's time for the AlfaBB Weber vs Spica rumble, round 326! :)

Since we've been through this before, I'll cheat and cut / paste my own take on the topic from a previous round.

SPICA is an ingenious, very complex mechanical device. Carbs are far simpler. As time goes on entropy inevitably favors the simpler system. Carbs don't have T/As, or pump belts, or microswitches. They don't have a huge tangle of irreplacable metal fuel lines. They don't destroy themselves if fuel pressure gets too low. Nearly all the maintenance and tuning can be done by a reasonably competent shade-tree mechanic - often without even needing to remove them from the car. Parts and expertise are widely available. For a daily driven commuter car in 1974 SPICA was probably the better choice, but for a weekend toy in 2011 I prefer Webers.

Given that you're looking for a roundtail just stick to '66-'67 cars, where Webers are original and correct.

-Jason
 

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He Went and Done it!!!

Looks like it's time for the AlfaBB Weber vs Spica rumble, round 326! :)

-Jason
OK, Oxy now you went and done it, pulled the scab off. ;) There are certain things we try not to re-open that are firmly established unsettled law. On this topic, it seems to run 50-50 here and no compromise just like Congress. Next I'm sure you'll ask about sump guards, another one of these lightening rod and divided topics. ;) And there are other hidden landmines (like in Super Mario).

I've run both and like them both for different reasons.

Spica is rock solid reliable if PM'd and set-up right. Ran the same pump, even with stretches of neglect, for nearly 40 years until Wes rebuilt it. Set-up 3 1/2 years ago and haven't touched it since. It starts first time, every time and runs smoothly. And there is no diddling every month or so. You want noise, put a stinger on - it's about the same. Sure, there is a rebuilt T/A (choke) every 3-6 years. Carbs: smell more (evaporating gas), more "snarley" but not so much with stock airbox, reportedly easier to roadside repair with bailing wire and bubble gum if you want to, just as much stutter off the line, and so on. Rebuilds can be expensive when done out and needed far more often than Spica pumps.

Though most racers race with carbs, I've seen no convincing data that they generate more HP, in fact Wes races with Spica on a helluva modified engine.

This is not from the perspective of a knowledgeable mechanic but a long-time informed user.

This is key: There are other differences between a 67 and 69 that are just as important to understand and choose between such as the dual boosted brake system mentioned above, and a 1600 versus 1750 engine (stock), and far lesser and bolt-on items such as 14 vs 15" wheels, and seat headrests, smaller brakes, etc.. The tranny's and rear-ends are the same at least (4.56).

Happy hunting! B
 
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