Effect of non-leaded fuel on 1964 390 engine?

[amillego]

Hi. I've just purchased an all-original '64 with a 390 in it. I was wondering if it's going to run OK (once I get it running) on unleaded gas. If not, what will I need to do to make it run correctly?

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[misty]

1. I use a product made by Gunk on my '63. It a Lead Substitute in a gray bottle. Previous owners used it. You can get it at O'Reilly's and most auto stores (also Amazon). Eventually going to pull the heads and have hardened valves and seats put in. I guess it needs the lubrication or you will burn valves and seats.

 

[amillego]

I use a product made by Gunk on my '63. It a Lead Substitute in a gray bottle. Previous owners used it. You can get it at O'Reilly's and most auto stores (also Amazon). Eventually going to pull the heads and have hardened valves and seats put in. I guess it needs the lubrication or you will burn valves and seats.

Misty...thanks for the information. I'll look for it and try it. Cheers, Gordon

 

[Olympus 200]

Hi. I've just purchased an all-original '64 with a 390 in it. I was wondering if it's going to run OK (once I get it running) on unleaded gas. If not, what will I need to do to make it run correctly?

I use a lead substitute additive (Castrol Valvemaster), although I have heard it said that for the 1000 miles a year I drive the T-Bird the engine will easily outlast me without the additive.

 

[Olympus 200]

I use a product made by Gunk on my '63. It a Lead Substitute in a gray bottle. Previous owners used it. You can get it at O'Reilly's and most auto stores (also Amazon). Eventually going to pull the heads and have hardened valves and seats put in. I guess it needs the lubrication or you will burn valves and seats.

I looked at having hardened valve seats installed on my 390, but on looking at the amount of material around the seats the reconditioner was reluctant to proceed. I got a second opinion and they agreed it was risky. I'd be interested in any other views.

 

[tbird]

Try this lead substitute- http://amzn.to/2wcXKJU

 

[captrick]

I had hardened valve seats put in all my 50's and 60's engines and never had a problem. I am still driving a 1967 427 - 425 hp engine even today. The only thing you want to make sure is that the timing is not to far advanced that the engine pings. On your 390 you don't want anymore timing then 36 degrees at 2500 rpm. It is a good idea to use 92 or better octane because of the higher compression of the older engines. Good Luck Rick

 

[Olympus 200]

Hmmm . . . interesting. I decided to go without hardened seats and installed the engine in March 2020 having spent 10+ years refurbishing it! However, the engine removed from the vehicle could be a candidate for hardened seats if they eventually prove necessary.

 

[Binky]

Hi. I've just purchased an all-original '64 with a 390 in it. I was wondering if it's going to run OK (once I get it running) on unleaded gas. If not, what will I need to do to make it run correctly?

I was told to put a gas booster in it ever so often. Amy car store will sell it. Maybe even Walmart

 

[64ZCODE]

I use a lead substitute gas additive with every tank of gas. I have no way of telling whether it's preventing degradation of the valve seats that would otherwise happen, but it seems like cheap insurance.

 

[Ezdarryl8]

Hi. I've just purchased an all-original '64 with a 390 in it. I was wondering if it's going to run OK (once I get it running) on unleaded gas. If not, what will I need to do to make it run correctly?

Yes