Re. the debate on manufacturing processes for cranks - the shaft is milled first, then the bits that rotate in contact with bearings and big ends are ground perfectly circular.

I would not be happy having an engine repaired if I had just spent 200k on a car

Just to put the tooling debate to bed.

A milling machine has historically been a linear action tool where the material is moved relative to a stationary cutting head.
The term now generally includes universal milling machines, which also allow the material to be rotated.

The main manufacturing process for a typical performance crank is tomachined from solid, not using a milling machine, but a CNC lathe. The journals are then ground to achieve the desired finish and the corners are fillet rolled. Additional features like holes and keyways are then added in a CNC milling machine. The whole thing then gets balanced in an automated cell which uses a CNC milling machine to add lightening holes to the balance weights.

There are lots of reasons that only 206 cranks will be affected, we can only guess at the cause. It's a testament to the quality of Ferraris tracking procedures that they can be so definite that it has only affected that small number of engines.

You'd rather stick with the out-of-tolerance engine?

The job they're going to do in a dealer is going to be as good as the assembly job in the factory (better in this case) so I don't really see the problem. Contrary to what appears to be popular belief, Ferrari engines don't descend from the heavens only to be humbly repaired by a bloke at the local dealership- an engine (and indeed a Ferrari) is a piece of mechanical engineering, and will be worked upon by trained technicians at the factory, and at the dealer.

In terms of the machines at the factory going out of tolerance, yes there should be checks in place to try and prevent it happening, but sometimes it will be unavoidable. A fault with the machine could see the tolerance slip more than it is reasonable to expect, and even if you calibrate it before each and every engine, there's a chance of it going out of tolerance. You could have increased measurement/inspection afterwards, but once you add checks beyond a reasonable level, you're adding cost without adding value to 99.99999% of cars. The decision at some point has to be made on whether the value added will justify the cost.

Perhaps Ferrari have got the balance wrong, but I wouldn't jump to conclusions without seeing the processes/sums.

id rather hand it back

Now guys....

I don't want to be rude or impolite, but it seems really unfair the above comment.
A factory know in all the world for the wonderful machines they produce made a mistake on 206 out of 13000 engines (0.159% margin) and they recalled immediately sorting the problem at no expense for the customer and no reported failures.
Just for comparison McLaren (that I admire) since last year had produced less than a hundred F1's, that's hardly a mass-production vehicle hence no reported failures, since they started producing the 12C I distinctly recall a problem with the IRIS that has been sorted only recently. There's plenty of literature on famous failures that has been ignored/lately addressed by the famous and precise germans (Porsche IMS, BMW S54 crank bearings and 320d's turbo....).
Accusing an italian factory of working bad just because it's italian and it's a cliché.....well it's stupid and only half telling the truth.

Sorry for the rant,

Enrico

Or not in the case of 206 engines??????

As the cranks are presumably the wrong size - or they wouldn't need to replace them - how did they get through a QA system? After all modern technology, which no doubt Ferrari will have (or if they don't they should have!), does all that sort of stuff very precisely and quickly. The only conclusion that I can make is that they didn't inspect them properly for some reason which then begs the inevitably question as to what else haven't they checked and whether the owners will pay for those to be fixed without being told it was really Ferraris mistake - OK I know its only a low % but its there and the crank is one of the most critical sized items in the engine.
Jim

If you can afford a Ferrari (or anything else interesting) why commute in anything ordinary?

Although maybe the chap commuting in the Ferrari is doing so to save his really nice cars for the weekend?

Ridiculous, and legally you wouldn't get very far with that argument.

Its nothing more than a minor irritation for a rational and logical human being