[Christine]

What do you fill your 1966 up with? I was told to use Premium but then some people mention marine gas. I live in Florida and there are several places that carry it but I think it’s a lower octane. (66 GTO 389 3 deuces)
So what do you use?

 

[Lemans guy]

I use the 93 octane pump gas,..10% ethanol. Runs fine and use Redline S1 complete fuel system cleaner per instructions as maintenance dose, like 2 ounces every fill up. Keeps it clean and running smooth.

You can use “pure” gasoline which is what marine gas is no ethanol. But it is more expensive and less readily available.

I found that switching back and forth was not good as they tend to run a bit different. So pick one and use it would be my recommendation. I gave up on the pure because it was too much trouble to always go to one of those stations. They are around but not as plentiful as the pump 10% ethanol.

 

[Lemans guy]

Pure or marine gas comes in different octane ratings as well. So you want the highest octane out of the pump 91, 92,93,....it prevents engine knock

 

[PontiacJim]

What do you fill your 1966 up with? I was told to use Premium but then some people mention marine gas. I live in Florida and there are several places that carry it but I think it’s a lower octane. (66 GTO 389 3 deuces)
So what do you use?

Read this:

Octane, compression & detonation

I grabbed several sources from both the internet and a few books to piece this together. The question of what octane should I use for my "X" compression engine seems to be an ongoing mystery. You can build your engine to any compression you want, but be aware of what octane you will need to...

www.gtoforum.com

 

[gtojoe68]

What do you fill your 1966 up with? I was told to use Premium but then some people mention marine gas. I live in Florida and there are several places that carry it but I think it’s a lower octane. (66 GTO 389 3 deuces)
So what do you use?

I run a mix of 93 unleaded from boat dock, no ethanol and 3 gals of 100LL Aviation fuel per fill up from the Airplane marina next door. Usually a 4 to 1 ratio depending on fill up. I’m lucky to live about 2 mile from Lake Washington though. Got 10:1 compression so in order to run the advance I like, I don’t have much of choice. Seems to work well. Cost is roughly $1.50 more than regular pump gas and since I only drive about 1000 mi annually, not too bad. Iron heads, mild build, Ram Air 2 grind cam. Had it rebuilt that way so it is fun to drive but still streetable.

 

[Christine]

I use the 93 octane pump gas,..10% ethanol. Runs fine and use Redline S1 complete fuel system cleaner per instructions as maintenance dose, like 2 ounces every fill up. Keeps it clean and running smooth.

You can use “pure” gasoline which is what marine gas is no ethanol. But it is more expensive and less readily available.

I found that switching back and forth was not good as they tend to run a bit different. So pick one and use it would be my recommendation. I gave up on the pure because it was too much trouble to always go to one of those stations. They are around but not as plentiful as the pump 10% ethanol.

Thanks! I think I’ve only filled up about five times and have been using regular gas haven’t noticed any pinging or anything bad but I was just wondering.
The act of filling up... yikes! that’s a crazy experience in itself! It’s so low and that gas tank comes straight out at you that it always spits back. I feel like I should be wearing safety goggles. I never ever know if I’ve truly getting it full or not. I end up adding a tiny bit at the end and when I keep making a puddle it’s full. (Not really but I feel bad spilling some every time.)

I run a mix of 93 unleaded from boat dock, no ethanol and 3 gals of 100LL Aviation fuel per fill up from the Airplane marina next door. Usually a 4 to 1 ratio depending on fill up. I’m lucky to live about 2 mile from Lake Washington though. Got 10:1 compression so in order to run the advance I like, I don’t have much of choice. Seems to work well. Cost is roughly $1.50 more than regular pump gas and since I only drive about 1000 mi annually, not too bad. Iron heads, mild build, Ram Air 2 grind cam. Had it rebuilt that way so it is fun to drive but still streetable.

wow that sounds complicated but basically marine fuel and aviation fuel. I could stop by and asked of the angels if they could loan me some fuel there just 3 miles down the road. 😂

 

[Lemans guy]

Sounds like you are doing the fill up just right! The smell of fresh gasoline in the morning,...we don’t get that any more with modern cars.

Love the photo.......the need, the need for speed

 

[Lemans guy]

So you may have seem me talk about this on the forum before. But I do recommend that you drop a bottle of Redline S1 Complete fuel System cleaner in your next full tank of gas. It goes right in the gas tank, then fill it up.

Here is why most the additives are snake oil, they drain your wallet and make some smoke.

There are only a few products that contain the one real chemical that can clean your carb and fuel system and even your valves, because it can withstand the temperature of combustion and dissolves the crud.

In the early 1990’s the chemists at Chevron Oil Company developed a chemical additive for their gasoline that did all these things. They add to their gasoline still today and advertise it as well, it is Poly Ether Amine (PEA), ....the trade name, or brand name is “Techron”.

You can actually buy Techron in a bottle at any auto parts store, even at Wal-Mart. But Redline actually has more Techron in it’s bottle than in the Techron bottle. In addition Redline uses two chemical carriers for the Techron, one is an octane booster and one is an upper cylinder lubricant. Both good things.

So you don’t need to know all this, just get a bottle at you local parts store and use it. It will keep your fuel system in top shape. I use a small bit on every fill to keep things in top shape.

That fighter jet might need some too...

 

[Christine]

Thanks! I think I’ve only filled up about five times and have been using regular gas haven’t noticed any pinging or anything bad but I was just wondering.
The act of filling up... yikes! that’s a crazy experience in itself! It’s so low and that gas tank comes straight out at you that it always spits back. I feel like I should be wearing safety goggles. I never ever know if I’ve truly getting it full or not. I end up adding a tiny bit at the end and when I keep making a puddle it’s full. (Not really but I feel bad spilling some every time.)

wow that sounds complicated but basically marine fuel and aviation fuel. I could stop by and asked of the angels if they could loan me some fuel they’re just 3 miles down the road. 😂 View attachment 140885

So you may have seem me talk about this on the forum before. But I do recommend that you drop a bottle of Redline S1 Complete fuel System cleaner in your next full tank of gas. It goes right in the gas tank, then fill it up.

Here is why most the additives are snake oil, they drain your wallet and make some smoke.

There are only a few products that contain the one real chemical that can clean your carb and fuel system and even your valves, because it can withstand the temperature of combustion and dissolves the crud.

In the early 1990’s the chemists at Chevron Oil Company developed a chemical additive for their gasoline that did all these things. They add to their gasoline still today and advertise it as well, it is Poly Ether Amine (PEA), ....the trade name, or brand name is “Techron”.

You can actually buy Techron in a bottle at any auto parts store, even at Wal-Mart. But Redline actually has more Techron in it’s bottle than in the Techron bottle. In addition Redline uses two chemical carriers for the Techron, one is an octane booster and one is an upper cylinder lubricant. Both good things.

So you don’t need to know all this, just get a bottle at you local parts store and use it. It will keep your fuel system in top shape. I use a small bit on every fill to keep things in top shape.

That fighter jet might need some too...

thank you. I wish I was closer to you you’re such a wealth of knowledge could be your gopher and go for tools to learn more Ill get some! It sounds like a sign as my dad used to drive for Standard Oil (later called Chevron) years years ago when he was in college. Does it matter if you’re just topping it off or does it have to be empty? . Because of course I just filled up yesterday

 

[Lemans guy]

You can just pour a full bottle of Redline into your full gas tank. Now not every full gas tank, you could do it every oil change.

or put a full bottle in your tank now let it all run thru. Then if you wanted to as a maintenace dose you could add 1.5 or 2 ounces to each new full tank of gas, or every other full tank of gas. And then do not do it when oil is changed.

lot’s of folks on here that help each other enjoy our cars.....

Put the Redline in and then drive it down the coast past Florabama and see how it runs!

 

[Christine]

You can just pour a full bottle of Redline into your full gas tank. Now not every full gas tank, you could do it every oil change.

or put a full bottle in your tank now let it all run thru. Then if you wanted to as a maintenace dose you could add 1.5 or 2 ounces to each new full tank of gas, or every other full tank of gas. And then do not do it when oil is changed.

lot’s of folks on here that help each other enjoy our cars.....

Put the Redline in and then drive it down the coast past Florabama and see how it runs!

Funny. I am like 6 miles from Florabama. Very SW edge of Florida up in the panhandle. Alabama line is so close no matter which way you go.

 

[Lemans guy]

Better yet go on past down to Lulu’s place in Gulfshores......

since Jimmy Buffet’s sister owns it you can get the Margariteaville vibe!

 

[gtojoe68]

Thanks! I think I’ve only filled up about five times and have been using regular gas haven’t noticed any pinging or anything bad but I was just wondering.
The act of filling up... yikes! that’s a crazy experience in itself! It’s so low and that gas tank comes straight out at you that it always spits back. I feel like I should be wearing safety goggles. I never ever know if I’ve truly getting it full or not. I end up adding a tiny bit at the end and when I keep making a puddle it’s full. (Not really but I feel bad spilling some every time.)

wow that sounds complicated but basically marine fuel and aviation fuel. I could stop by and asked of the angels if they could loan me some fuel there just 3 miles down the road. 😂 View attachment 140885

That is a great photo. Love that old school stance. And the fuel fill up is a bit of a dance ( you can’t fill the AV gas directly into your car as there’s no road tax paid on it). But it’s all part of the game. I do love the smell of AV gas in the AM. I miss the Angels flying over Seafair here in Seattle, they used to fly right over the long boom, like 150 ft off the deck. What a rush. Not anymore. you could literally see the freaking pilot in the cockpit when they were inverted. But that was the 80’s....