Ok so dad was looking through the Haynes manual, and being the non-engine person I am I only have a small idea of what he was going on about. He was wondering if, for a 1979 1.3, is it possible to run the car on straight unleaded fuel or is it necessary to use a lead additive (assuming it still has the original engine)? He seems to think the it's possible the head (that's the bit that the lead affects, right?) is hard enough already judging by something to do with the specs...

Also how many teeth do the 1.3L cambelts have/is this the right part: clicky clicky ? Oh, and is that a good price? I know the 10USD is fairly cheap but its $35AUD by the time I get it here so and aussies know if that's worth it?

Thanks in advance guys.

Regarding the unleaded bit, all of Fiat's aluminium cylinder heads (from necessity) are up to running with unleaded fuel, on top of that the same engine was supplied to the USA where unleaded fuel was already mandatory at the time. Fiat have placed a caveat on this stating that you should not run the engine under continuous heavy load as this can cause premature wear on the valve seats - this is more a case of protecting themselves legally than a serious consideration.

I've had one cylinder head converted to specially hardened seats and it made absolutely no difference to performance or wear (and trust me on this I was not gentle to the engine). The biggest concern is not the valve seats, it is the head gasket and the head bolts.

The design and layout of bolts/studs used on the X1/9 engines despite their variations all have the same problem - that stretch bolts were used and are rarely replaced when the gasket is changed (Fiat did not publicise that they were stretch bolts at all) coupled with the fact that the later head gaskets used by Fiat have a tendency to rot with the oil and water paths cross contaminating. On top of that the fire rings between 2 and 3 tend to burn out (this is usually where you find out you have head gasket failure).

It may sound like a head gasket failure is inevitable but despite the above comments the engine is very, very sturdy and can take a huge level of punishment even when getting a bit flaky. The real point is that when it goes you have to do the job properly and not just make do. Replacement bolts are available from Fiat still (in the UK at least) and there are pattern part manufacturers that still support these old engines. Getting a new cambelt (and tensioner) shouldn't be difficult or too expensive (at source - I know the shipping can be a killer).