Preserving the Engine - Oil and Fuel

[matt2491]

I've become aware that with these older engines, they used to run leaded fuel and different oil. These days, all we're offered is unleaded.

Is unleaded fine to run in these engines? I think I read somewhere that the leaded fuel helped something to do with the valves???

I just wanted to see what everyone is running for gas and oil, and if there are strong opinions for any particular types, etc...

Right now I've been pouring high-octane unleaded into the tank and lubricating the engine with Advance Auto store-brand 10W-30 oil. I'm wondering if I'm ultimately hurting anything.

[bertha66]

Yes, the lead was for the valves. I have been running unleaded in my truck ever sence they stopped making the leaded. I do not have the hardened seats in my engine, it is a 67 390 HiPro Fairlane engine. From what I understand, if you do not run it 80% of it's rated RPM's it will last for years. I have been driving it sence 1980 with the 390 in her. My only problems now is with cabon build up, so a octane booster may be needed.

[PROSTOCK]

Unless your engine is high compression or your timing is such that you have pinging, you are wasting your money buying high octane fuel.

The lead did help lube and cool the valves. As mentioned, you are probably fine leaving it and running unleaded gas. I installed hardened exhaust seats in my heads as a precaution when the engine was rebuilt. I have seen FE heads in which the exhaust valves had eaten their way into the head about 1/8".

I'd guess that any oil you buy today is better than what was offered back in the day.

[64F-100]

I recently had this discussion with a knowledgeable buddy of mine; he said that back in the day, engine oil contained a higher amount of zinc - today it contains virtually none. The zinc was added to the oil in order to lubrcate the cam lobes on a slider cam. Most modern cams are roller style, so the extra lube is not needed anymore, thus the reduction in zinc. Engine oil containing zinc can still be found; it is usually labeled as "racing oil", such as Royal Purple. If you wanted to spend the bucks, you could go that route. I am using valvoline 10w30 right now. I don't thin the premium fule is going to get you much unless you are trying to clean out your fuel system; I heard that some good sunoco 94 or shell 93 works well for that...

[jowilker]

Matt, You can't buy leaded gas, so run the cheapest unleaded that you can find. The lead lubed the valves but it ate spark plugs and exhaust systems. I got two Tauruses that I changed the factory plugs after 100,000 miles, impossiable to do with leaded gas.

Oil, regular ol dino 10W30 for these truck changed every 3-5,000 miles is all that is required.

Gas additives and oil additives is a waste of your money. IMHO


John

[matt2491]

This all sounds about right.

Originally Posted by 64F-100

I don't think the premium fule is going to get you much unless you are trying to clean out your fuel system; I heard that some good sunoco 94 or shell 93 works well for that...

Yeah that's pretty much what this guy I trust told me to run the high octane stuff for.

[instig8r63]

Valvoline Racing Oil still contains the zinc that our flat tappet cams like to have. Also the diesel rated Rotella and Chevron Delo contain zinc.
The reason oil companies discontinued zinc in oil is because virtually everything has roller cams now, but more so because the zinc kills catalytic converters.

[matt2491]

Didn't somebody say that they also kill spark plugs and exhaust systems?

[jowilker]

My oldest son had one of those SVT models with a premium only sticker a while back. He was feeling good about riding around in his pocket rocket, and the price of gas started shooting up, and cramping his wallet. He thought he'd try a tank of the cheep stuff, to his surprise the car ran fine. It took a while but it wasn't too long before he was only running the cheep stuff like his dad.


John

[matt2491]

So it doesn't matter.