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1982 Spider Veloce
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Was asked a question today that I could not answer. Have a 1982 Spider Veloce and was asked if I needed to use a lead additive in the gasoline. I have not added any but this car has not used half a tank since I got it. So the question: does this engine have hardened seats and valves and not need the lead or is it a design leftover from before the advent of the unleaded gas?
 

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It has hardened valve seats, so, no, you do not need to worry about leaded gas or lead additives.

And, you didn't ask but I'll say it anyway - unless the engine has had significant internal modifications (high compression pistons) it does not need premium octane gas. The European method of measuring octane (RON) is different from the USA measurement (PON). Thus, the European owners manual may say "92 octane' but that is the equivalent to USA 87 octane.

1647928
 

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Eric, would it be the same with New Zealand octane ratings?, as 98 or 96 is considerably more expensive than 91.

And yes, I don't think an Alfa Romeo has ever needed lead

Answer:
Anti-Knock Index (AKI) or (R+M)/2Edit
In most countries in Europe (also in Australia, Pakistan and New Zealand) the "headline" octane rating shown on the pump is the RON, but in Canada, the United States, Brazil, and some other countries, the headline number is the simple mean or average of the RON and the MON, called the Anti-Knock Index (AKI), and often written on pumps as (R+M)/2.
Pete
 

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When I joined the Alfa Club in 1978, leaded super was disappearing from the pumps here and fellow Alfa owners were all up in the arms about that. Opinions went left and right, it was pretty much like the ZDDP thing now.

I've never heard of an Alfa head suffering valve seat recession. Of course they're aluminium and need steel seats; but take for example a Lotus Twincam head, which is a rough copy of an Alfa head, and they did suffer from valve seat recession. I bought one where two exhaust valves would not close anymore. The steel seats were just not hard enough.

All cars sold in North America from 1972 were required to be able to run with unleaded fuel. I never heard that Alfa had different heads for our market.

When I got my Twincam head done by a racing machinist, I asked him if valve seat recession was a common problem. He said it was a real problem with the surviving pre-1972 American heads, all cast iron and without inserted seats, and especially the low performance ones - the exhaust valve spends more time on the seat and have less time to cool. He said even some specific more recent cast iron heads had a problem, because the seats were just induction hardened and that was just not enough.

Another example of Alfa doing things right.
 

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Yeah I guess Lotus, being English, opted to save money by using soft valve seats.

So many English designs ruined by production cost savings ... the Japanese learnt from this and did not cost cut on their product but saved money in how they produced their cars, through improved manufacturing processes
Pete
 
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