I have been roaming through the forum for additional information about these exciting cars. Especially the details about the Var 1016 is fascinating ... although I am not convinced I understand it all
I came across this engine number 818.540.2264689 in one of the threads. Is this an engine number, an engine type denomination or something else? If it's an engine number why does it have 7 digits after the 818.540. Shouldn't it be 4?
Also I was reading about the Solex DDHF 45 which apparently are their weight worth in gold. General question about carburettors: What is the 'best' carburettor for a 1.6: Solex, Dell'orto or Weber, i.e. what are the pros and cons of each carburettor setup?
I think you are confusing the cilinderhead casting number for the engine number.
The engine numbers starts, like the chassis number, always with 1001. And run till the last of the line.
regarding the DDHF carbs. It al started with the DDHF40 Solex. Made for the factory prepaired 1300HFSs. This casting was later bored out to become the DDHF42. The common 1600 Carb. For the first batch of 1600s the so called VAR1016 the DDHF40 casting was bored out to 45mm to become the DDHF45. All versions were not particulairly well made and often gave 9and give) problems with for example quickly worn out spindle bushings. For as far as I know all Webers and Dell Orthos have rolerbearings and are generally excepted as the better carburator. The only problem is their bigger physical size. Hence the need for a bigger manifold, being it a full replacement or an extention piece.
I took the liberty to upload some pictures of different settings. http://fulvia-hf.myjalbum.net/Fulvia%20 ... 0sessions/
William is correct–you’re looking at the cylinder head number, not the block number. The block number can be found on the block, near the starter motor, where the block joins the flywheel housing. As William noted, it will have a 4-digit extension, beginning 818.540.xxxx, and the first engine in the series was 818.540.1001.
I think there’s a lot of nonsense written about Variante 1016–mostly, I suspect, having to do with the original homologation. In order to homologate the ‘special’ engine parts, enough of those special parts had to be produced and made available to the public, at least as a option. But it wasn’t at all unusual for manufacturers to make fewer special cars or special parts than they claimed for homologation. Officially, the first 600 1.6HFs were supposed to be Variante 1016, but I don’t know anyone who believes this. (And if there is anyone who believes that 600 were produced, I like him to explain why so few of them still exist).
I’d also agree with William regarding Solex, Dell’Orto, and Weber. The Solex DDHF45s are, as you say, virtually unobtainable. Fairly early on, the homologation was amended to allow the works cars to use 45 (and later 48) Dell’Ortos or Webers, both of which required an intake manifold with wider runner spacing.
I think there was a very good reason that the factory didn’t stick with Solexes for their competition cars–Dell’Ortos and Webers seem to be more ‘tunable’ and more reliable that Solexes. In any case, reproductions of the “Group 4" manifold needed for Dell’Ortos or Webers are readily available; one of these is on my HF, along with a pair of Weber 40 DCOEs. The 40 DCOEs are a very tight fit–they just barely clear the hood (bonnet); 45 DCOEs will not clear without some modification to the manifold or hood, and 48DCOs are just silly for a street car, IMHO.
As a sideline on intake manifolds, I have heard bad stories from a number of people who purchased theirs (newbuilt repros) and who didn't fit without some major grinding on the engine-side, i.e. not a simple angle-grinder job.
