Unleaded gas ?

[pluto]

Can I run a 1970 Fiat Spider on unleaded gas or do I have to add lead substitute ?

[spidernut]

Lead was used to boost the octane. You can run unleaded, but may have to go to a higher grade to avoid pinging.

[vespistiSF]

Yes you can. Some people recommend using the lead substitute to avoid premature wear of valve seats. All my old cars run on premium unleaded. I don't add lead substitute on any of them and haven't had any problems.

[pluto]

Thanks to all.

[GeorgeT]

Your bigger problem is ethanol in most of the gasoline sold today. The fuel lines and carburator seals in older cars were not designed to ba stable with alcohol and deteriorate much faster. Fermented and distilled corn should be made to drink, not burned in cars.

[majicwrench]

The lead also helps with valve seat longevity.
Fiat, with their alum head, has nice, hard valve seats in em.

I have a 64 Chev PU, with cast iron valve seats, and without the lead, it beat the valve seats waaaayyyy down. I kept adding shims to the valve springs so I could drive it. Finally replaced the head.
Anything that you really love, without hardened valve seats, should really have some help if it is driven much.
Keith

[maytag]

The lead also helps with valve seat longevity.
Fiat, with their alum head, has nice, hard valve seats in em.

I have a 64 Chev PU, with cast iron valve seats, and without the lead, it beat the valve seats waaaayyyy down. I kept adding shims to the valve springs so I could drive it. Finally replaced the head.
Anything that you really love, without hardened valve seats, should really have some help if it is driven much.
Keith

+1
If you don't plan on getting into the motor, you should plan on using a lead additive.