Seems that I was misunderstood. I never said that any SVA was made of aluminium. According to my sources I have following story:
The Giulietta Sprint Veloce was introduced on April, 20th in 1956. It was a standard Giulietta Sprint steel chassis but it was called ‘Alleggerita’ because of replacing the doors and hoods with aluminium parts and it is said that they were also using thinner steel sheets where possible, not unusual since the Sprint in his early days was more or less handbuilt. It had lighter seats and bumpers, no sound deadening material and perspex side and rear windows. Alfa Romeo saved around 100 kg against the standard Sprint and stated 780 kg dry weight. In Motor Revue 19 from 1956 they weighted the car with 844 kg without fuel (MI 304694, to my records possibly SVA #01536).
This picture is showing one of the first SVAs in a press photograph at Alfa Milano or Bertone Torino:
The lightweight door from inside (MI 304694)
So the early 1956 SVA #01849 with standard steel doors would never be correct.
In late 1957 Alfa Romeo presented a revised Sprint Veloce: The so called “Confortevole”, a standard Sprint body with all steel parts, but with the door frame of the Alleggerita series, this time with windup glass windows and full interior (article in Auto Italiana 2 from February, 20th 1958). It is said that the Confortevole (or “comfortable”) was built side by side with the Alleggerita for a time, but when the expensive aluminium parts were running out, only the Confortevole survived until April 1958, when the 101 series arrived (“Auto, die Geschichte machten” by Dirk-Michael Conradt). See this pressphoto, used from early 1958 on: same place, same season (trees) but a new building in the background (Hoechst office)
Since Alfa Romeo did not use the term “Confortevole” regularly, it seems that as usual there are many intermediate versions. The last SVs had even standard Sprint doors without window frame (see Lionel Velez’ #06611, maybe the last ever built). And of course they must have nearly the same weight as the Sprint Normale.
The Sprint Veloces have the standard Sprint VIN but an “E” (for Elaborata) was stamped between 1493 and the running chassis number. Often the chassis number is not stamped very well, so it would be easy to make a Sprint Veloce out of a Normale by taking a Veloce engine and a rev counter from a rusty Spider, throwing the standard seats away and put racing seats in it. In the early 1960’s you could already buy aluminium and fibreglass doors for your racing Sprint. Some cars had even Alleggerita doors with the 101 grille, so we do not know if it was an original SVA repaired with the later front due of racing damage, or it was a 101 Sprint (SVII) with lighter doors.
But with the additional Bertone number it would be easier to identify a car, since the Alfa chassis number and Bertone’s own number should meet the timeline:
Lession in mathematics
SVA #04347 has the Bertone number 77468. The former owner told me that the number behind 77 (i.e. 468) could probably be the number of the SVAs that were built and that would meet the official estimate of up to 600 cars (SVA #04347 is mid 1957). I know two further Bertone numbers of correct SVAs: 77411 for SVA #04127 and 77025 for SVA #01722, made one year earlier than #04347.
So from chassis #04127 to #04347 they stamped only 57 numbers? And in a full year only 400 numbers?
And, hah, SVA #01722 is the 25th SVA chassis ever built according to Anselmi!
And, surprise, surprise, it has engine #30025.
Next
SV #06230 has Bertone’s 655618, SV #06575 has 655964, both are 1958 without plexi windows, thus SVConfortevoles (SVC). You can see that the Bertone number follows the Alfa number by only one.
So why Bertone gave two different numbers to its 750 Sprints?
I do not know which number a Sprint normale has, but when Bertone had marked 77… for the Sprint Veloce and 65… for the later SVC (and the earlier Sprint normale?) body, you can take 5964 from SVC #06575 and there will be a good 600 left, the same number of produced SVAs as given by Alfa Romeo. This would mean that all the later 750 Normales and Veloces (i.e. SVCs) had the same body. And this could confirm that the original SVA had some special body parts, too, and not only lighter doors.
Engine
But also when you look at the engine numbers from the last SVCs, i.e. #06056 (produced 19580218, without door window frame, too) has engine #30799 and #06575 has engine #31038, and put away the few Spider Veloces made up to April 1958 you will get a number of around 600-800 engines built which will also meet the procuction estimate for SVA+SVC together.
All in all you will come always up to 600 SVAs and 200 SVCs.
And what do the Hull/Slater book state? 252 SV for 1956 and 458 SV for 1957 and only 40 Spider Veloces (SPV) these years, but less than 800 engines produced.
This would come up to Anselmi’s Giulietta book: 98 of the first 100 SVs were built within only three months since presentation in April (#01380 to #02158). All 100 have continuing engine numbers from #30001 to #30100. And of course all were lightweight. And there are many later SVs like #03999, #04127, #04227 and #04229 that are real Alleggeritas with aluminium parts and correct door windows.
Now my question: Joseph and friends, what Chassis and Bertone numbers do your Sprints and Sprint Veloces, Alleggeritas and Confortevoles have? Do they begin with 65… or with 77…?
I would bet Lionel’s SVC #06611 begins with 65 (something like 656000?) and every original SVA up to chassis #04500/#05000 should have aluminium parts and its Bertone number beginning with #77...
To be sure, we will need much more than these few VINs.