Best "Quality fuel"

[99gst_racer]

Assuming the gas pump's hose is about 12 feet long and has roughly a .75" ID, if would still only hold about 35 ounces (27% of a gallon). I've never thought about this before, but it is kind of interesting.

 

[habitatguy187]

We should all just start purging the line onto the ground before we start pumping it into our cars.

Zoolander style, of course...

Thinking about though it's probably not worth it to only put in 1 or 2 gallons of 93, because you'll probably just end up with 90ish. When I add gas I try to wait until I'm pretty low so that I can add more than a couple gallons just for this reason.

 

[turbosax2]

Assuming the gas pump's hose is about 12 feet long and has roughly a .75" ID, if would still only hold about 35 ounces. I've never thought about this before, but it is kind of interesting.

And assuming you pump 13 gallons of "93" into the car after the person before you used 87, your new octane rating is roughly 92.9.

 

[Black91TSiAWD]

So let me get this straight, because Im kind of confused. Would the gas thats still in the line be a part of the gas the previous pumper paid for, or would it be included in the next persons pump? I cant see how they would measure that, or regulate. If thats the case, either way someone is getting dicked. Im thinking theres maybe a check valve or something that stops the fuel from entering the hose after you stop pumping, or maybe not. You would think there would be a big to-do about this if there wasnt a reasonable explanation. Gas pumps have been around how long?

 

[i_nick_2005_i]

Lucky! They dropped the 94 from the few stations around me that had it. I wonder why

Well, I just went by my local Sunoco (haven't been there in quite a few months, it's alittle out of my usual course of travel). And they replaced their 94 Octane pump with a diesel pump.

What is the world coming to...........

 

[99gst_racer]

So, I just had to know how the pump works. For anyone that is interested:

One of the first things that a customer will notice at the pump is the variety of choices offered. In most cases, a dispenser will offer several grades of gas -- sometimes as many as five -- each with a different octane rating. The desired octane rating is usually chosen simply by pushing a button. Does this mean that there are five different underground tanks feeding into that dispenser, each offering a different grade of gas? That's not usually the case. In fact, the dispenser can produce as many grades as it wants from as few as two underground tanks, as long as one tank contains the highest grade of octane available at that station and the other contains the lowest. The grades are blended together at the pump -- not unlike the way you'd blend gin and vermouth to make a martini -- producing a kind of octane cocktail. The precise proportion in which the grades are blended determines the octane of the gas that enters the customer's tank.

This feat of gas pump bartending is performed by something called a blend valve. This valve has inputs consisting of two grades of gasoline, each from different tanks. A single, moveable barrier called a shoe is connected to both in such a way that it can be moved across the inputs with a single motor-driven ratchet. As the ratchet opens one valve, it closes the other valve in precise but opposite proportion. This means that when one valve is, for example, 90 percent open, the other valve is 10 percent open, creating a mixture that consists of 90 percent of one octane and 10 percent of the other. By shifting the ratchet back and forth, the blend valve can produce any octane of gas, ranging from the highest to the lowest grades stored in the tanks -- and all octanes in between.

When the customer removes the pump handle from its place on the side of the dispenser, this action activates a switch that starts the dispenser operation. (In some cases the switch is spring-loaded and activates automatically; in others, the customer must raise a small lever manually to begin the process.) At that point, the customer simply inserts the nozzle into the car's gas tank and pulls the lever. Stopping the flow of gas is just as simple -- the customer need only release the lever to cut off the stream of fuel.

But what if the tank fills unexpectedly to the brim and the gasoline threatens to overflow? As anyone who's ever operated a gas pump knows, the pump will switch off automatically. But how does the pump know when to stop pumping?

As the gas level in the tank rises, the distance between the dispenser nozzle and the fuel grows smaller. A small pipe called a venturi runs alongside the gas nozzle. When the end of the venturi pipe becomes submerged in the rising gas, it chokes off the air pressure that holds the nozzle handle open and shuts down the flow of gas. Unfortunately, this shutdown can sometimes happen before the tank is full as the rapidly flowing gas backs up on its way into the tank. This can cause the gas handle to spring open before pumping is complete, leaving the annoyed customer to squeeze the handle again and risk the possibility of overflow. Pausing briefly will allow the gas to continue into the tank and the pump nozzle to start pouring gas again.

So, it sounds like fuel will be setting inside of the hose between customers. But being that it is mixed at the pump itself (using mostly what is already in the hose anyway), the amount of difference that it makes to the octane value is very small (probably less than 1%).

 

[snakeyes711]

I think he's talking about the hose that's attached at the gas station pump. How much fuel is in it after someone has just filled up on 87oct and you hit the 93 or in my case 91oct button.

I wouldn't think there's quite a gallon. Then again I don't know... I have wondered though if I'm even getting 91 octane at all when I fill up, or if they're just taking my money for 87 and calling it 91. More less, all buttons lead to 87. Or maybe there was a new guy that delivered the fuel and put the 91 oct in the 87 tank and vice versa.



Edit: Damnit, brian types faster than me...

Actually its only about a half a glass full, my dad, and one of my best friends used to do this. They'd say you could get about a half gallon more if you drain the hose. When I tried turning the hose up, and draining it I was not impressed at how much REALLY came out.

I appreciate someone adding Sunoco to that, those were just names that popped into my head, and I couldn't think of anymore. I didn't dare put Marathon even though there is one here local that carries race fuel, its supposed to be 99 or 100 octane, but it costs about four bucks a gal.

I'm suprised how many people who use Sunoco fuel, I can't even think of one Sunoco station here in town... Its either Amoco, or Shell or such. There IS one 76 gas though.

Also almost all the stations here in NC carry 93, why is it other states its only 91 oct.?

 

[brownfinger]

All this stuff about how much fuel is in the hose is an interesting nugget of thought, but only since our little cars have such tiny little tanks. My truck's capacity is 38 gallons!( v10 F250)

For the record, on this thread, I go Amoco/BP. They're ever-present in the mid-west and points east. But really, I started using it because it's the card that my mom gave me back when she paid for my gas ( I think it's the card her dad gave her back in '67 ). After a while, I started doing it 'cause the car always ran great. After 215,000 miles on a diet of nothing but Amoco gold, the car finally had to be euthanised due to an irrecoverable front-end collision. Never rebuilt, no bearing problems, no other internal problems, original head/never even removed once, it just kept running strong 'till the end. I figured, "why not go with what works?".

I know it's over-kill using premium on an NT with/out a knock sensor, but hell, it was running like a top when I got hit head-on back in August.

My replacement for that car was purchased in Spokane, WA. On the way back, in Montana, I got to see how all the octane is lower. In high-altitude zones, the premium is 89 octane! What do all of you mountain boys and gals think about your gas?

 

[91Tsig]

I do a lot of driving so I usually just get whatever has 93 and is on the way to where I'm headed at the time but only brands like Hess, Shell, Sunoco, Mobil, etc., and the occassional Richdale location which I think uses Gulf.

If I had a choice though I'd prob stick to Shell V-power. Say what you will about it but I've never had a bad experience with Shell...at least the V-power stuff.

 

[snakeyes711]

I used to go with Exxon, Amoco, BP. Did anyone see that BP won the bid in Iraq for that oil field?...After soo long of BP being banned from being allowed there, suddenly their government auctions off a huge oil field, and BP gets it....

 

[My1GLaser]

I used BP/Amoco in all my vehicles for the last 15 years until they recently started putting in this invigorate shit. I noticed an avg of 1 mpg worse fuel mileage on my dd, which gets about 300 miles/wk and I track it on every fill up. I also started picking up knock on the DSM where I never used to before. I had to pull about 2* to run the same boost as I have for over 1 year. I switched to Exxon and the problem went away in both.

 

[gsxAWDdsm692]

Shell V-Power.

Used to get Sunoco but they don't sell 94 at my local one anymore.

I'm pretty sure the gas pumps suck up all the fuel back into the tanks clearing the line after every transaction.

 

[Mi'nightEclipse]

I'm with Cheveron for my gas. Shell is okay but Chevron seem to last longer in my tank.

 

[Staytuned]

Right now I use Sunoco 94 plus one bottle of NOS race blend octane booster with nitro methane.

So far so good. 33 psi and 16* of timing.

 

[Mi'nightEclipse]

You guys are lucky to get 94 octane rating. Here in Oregon we get 92 for our maxium octane in our fuel and 10% Ethonal (I think that's spelled right).

 

[MY1GDSM]

I Didn't pick any because my "Pump gas" isn't on the list
I Run US Ethanol 105 ocatane E85

 

[brownfinger]

I used BP/Amoco in all my vehicles for the last 15 years until they recently started putting in this invigorate shit. I noticed an avg of 1 mpg worse fuel mileage on my dd, which gets about 300 miles/wk and I track it on every fill up. I also started picking up knock on the DSM where I never used to before. I had to pull about 2* to run the same boost as I have for over 1 year. I switched to Exxon and the problem went away in both.

Good to know, thanks.