[Spridgets] Question

[Kirk Hargreaves]

A Porsche has it's cams driven by an internal chain.  . the same as I think
about it as the straight 6 Jaguar engines hailing from the 1950's (and
possibly earlier).

Many high end cars have their cams driven by an internal chain with a
tensioner which needs very little maintenance, if any, compared to an
outside belt drive.

The Ferrari, and I am guessing the Lambo and other super high end cars have
their cams driven by outboard belts . . which need to be changed out at
around 30k miles.

With the Ferrari, I understand that it is a big process in that the engine
has to be pulled to change out the belts.  I have read that it can cost up
to 10k to have the dealer change out the belts in a Ferrari.

So why would Ferrari, as well as others, go with an outboard belt drive on
their cams?

Is it because the system is lighter, gives a better response, or?  I am
guessing that the thought is that outboard belt driven cams enhance
performance?

Just a question that has been in my head for a while. . I never have heard
anyone explain the theory behind the out board belt as opposed to the
internal timing chain for driving cam shafts?


Kirk
Pushrod Drive 1275