Is it possible to convert a leaded gasoline engine to one that burns unleaded gas?

Dear Car Talk

Dear Car Talk | Aug 01, 2001

Dear Tom and Ray:

I'm transferring to Italy and am thinking about buying a well-maintained but older Fiat. Here's the problem: They all burn leaded gas, and the Italian government is thinking about requiring cars to burn unleaded gas in the near future. How much does it cost, and what does it involve to convert a car from leaded to unleaded fuel? -- Keith

RAY: Well, the operative word in your question is "thinking." As in "the Italian government is thinking about requiring ..." If the Italian government is just thinking about it now, it's going to be decades -- and another thousand governments -- before they ever get around to it.

TOM: And besides, it doesn't cost anything to convert a car to burn unleaded gasoline. You just put the unleaded in the tank, and you drive.

RAY: When the United States first changed over in the 1970s, there was some concern that valve seats would be at risk, since the lead protected the valve seats from the pounding they got from the valves.

TOM: But it turns out that, for the most part, the old valve seats have done fine without lead. We've done very few valve jobs over the years on cars that were designed for leaded gas. And certainly those problems would have shown up by now.

RAY: And besides, you're talking about buying a Fiat, Keith. A Fiat! There's hardly been a Fiat made that would deserve anything other than putting gas into it and driving it.

TOM: So I wouldn't spend a lot of time worrying about this, Keith. Those huge Roman potholes that Julius Caesar used to complain about will be a much bigger threat to your old Fiat than unleaded gas will ever be.

Get the Car Talk Newsletter