Unleaded gasoline

[TheFearlessFury]

I'm sure this has been asked before, but what's your guy's verdict in using unleaded gas in your classics.

Every once in a while I'll dump lead additives or substitutes in my 71. But it doesn't seem to make any difference in running quality, and my engine doesn't tick after I turn it off, which I heard is a sign that something might be wrong in regards to the fuel you use. I read a somewhat obscure article on the 71 Fury (written in 71) that said the 71 was built to run on "low lead fuel" no idea what that means, but I kind of take it to mean that it doesn't really need lead additives.

I only use premium because I tried running the cheap crap in my 68 for a while and it would stall like crazy.

Anyway, what's your guy's verdict, I know the 72s are good to run on whatever, but what about the 71?

Also general fuel discussion, what do you use, what does gas cost where your at, etc.

 

[Big_John]

Additives do nothing except empty your wallet.

Mopars have more nickel in the cast iron alloy they used then the other makes. It makes the block and heads harder and the valve seats are less vulnerable to wear from lead free gas.

 

[Rwc]

I believe you are fine. Don't think it's such a big deal as some cars. I add treatment every other tank or so for the ethynol myself.

 

[fury1]

The lead is needed for the valves in older cars. we run lead in the 57 Lincoln we have. I run no oxy 91 in my 66 300 and regular 89 in my 75 Chrysler. I've tried running higher octane in my 75 but it didn't seem to make a difference. I was also told that unless you are racing your car or running high rpm the lead isn't really needed... Not sure if that's true or not. Maybe some older members on here can tell you exactly.

 

[Rwc]

Isn't it "the higher the octane the cooler it burns?"

 

[TheFearlessFury]

Thanks guys, with gas prices so low it feels pretty good filling my Fury up for under 50 bucks lol.
I think my Dads GTO runs some insane high octane crap , it's got the 400 with some work done to it. Nice car but the gas is really spendy, won't catch me running that in my Fury.

So what's the deal with the 'low lead' fuel anyway? Was that actually a thing? Anyone know the article I was talking about? It was like Mr. Somethingorwhatever

 

[70bigblockdodge]

Isn't it "the higher the octane the cooler it burns?"

Only true is certain octane is needed to prevent detonation (pinging or knocking) that's when temperatures go waaaay up, hence the partial truth to runs cooler. You really don't need lead for a lube on vavle seats exceptions would be very radical can and its high valve spring rates, sustained high rpm and load, big truck,RV, road or endurance racing, lastly high mileage like 25,000 or more a year, and even then it would take a few years to wear seats. You are probably safe unless one of these is in your future, and really they are all severe duty which will wear anything out quicker.

 

[Big_John]

Isn't it "the higher the octane the cooler it burns?"

In a nutshell....
With low octane gas in a high compression engine, the gas mixture ignites under compression and before the spark plug fires. Higher octane allows the mixture to compress more and ignite with spark rather than the heat generated with compression. It actually burns a little slower as the flame travels across the piston.

There's nothing to be gained by running higher octane than you need.

 

[TheFearlessFury]

So no reason to go out and run racing fuel in a 318 LA then lol

 

[1978 NYB]

Not unless you're running 10:1 pistons or better.

 

[saylor]

i put in a bottle of lucas the skinny bottle with the green top - i dump a bottle in every so often.
dunno if its getting me anything, but it feels good.

 

[live4theking]

With the price of gas down, regular $1.89 and premium at about $2.20, I'll be running the premium. As far as additives my only concern is the ethanol which I use Star-Tron to combat. I use it especially in the mower, snowblower, chainsaw... I haven't had any problems with them gumming up. Additionally there is a 2 stroke marine oil with TC-W3 in it. I've read an article where they recommended 1 oz. for every 5 gallons.