[396ssrat]

Interesting list, I've been filling my Silverado with VP 87 octane and I don't see VP on the top tier list. Go figure.

[NA18CamaroSS]

Originally Posted by foshjowler

I ran around with my Cobb AP up, and the only time I ever saw anything other than ideal was when I filled up at a random Shell station on a trip, and even that wasn't bad.

When I was working for a tuner in southern California, the only gas we had knock issues with was Shell. I had a built 11.5:1 VTEC motor in my Type-R and it was tuned to a tee on 91. I filled up at a Shell station and the car started knocking; I thought that perhaps they had pumped 89 or 87 into the 91 tank. Then, whenever we had a car knocking more than usual or making less power than expected, we started finding that the common issue was Shell gasoline. Forced induction Mini's that made less than expected power always turned out to be running Shell.
Running E85 (78-80 % ethanol) in my Camaro so the brand of gasoline available in my area is moot.

[2SS Capt]

Originally Posted by NA18CamaroSS

Forced induction Mini's that made less than expected power

"Forced Induction Mini's" made me laugh...

[3.8TransAM]

Originally Posted by SSDan

My son is a petroleum engineer and has explained gasoline refining to me. All gas is refined to the same federal standards and only two octanes are produced on the east coast - 87 & 93. Other octanes such as 89 and 91 are just blends of 87 and 93.

The additives are added into the tanker at the point of fill at the refinery. Top tier companies each use their own proprietary blend of additives. Some non top tier stations use some additives and the El Cheapo stations use none.

So Ember has the straight scoop for the what and how of top tier.

Ember - I would say that the occasional use of non top tier is fine. Just keep using that Costco gas as much as possible.

This. I work in a refinery and this is how it goes everywhere.

[BlaqWhole]

I've used gas from every station except for Wawa or QuikCheck type places. I very rarely use Exxon as I don't really care to pay an extra $1.10 per gallon more than the other stations. Same with BP and Shell. I typically use Citgo, SpeedWay, and some of the other same tier stations. I have been doing this since I started driving at 17 years of age. And I have never had a fuel related engine or fuel related failure or anything of the sort. As far as I'm concerned, these statements and recommendations are simply to keep the larger companies making more money than everyone else.

Now what others do with their ZL1 is their business. But I have no problem using the lower tier stations. There is even a private gas station/shop around the corner from me that I go to from time to time. The old guy who owns it always comes out and tells the same jokes. I don't think he ever remembers be. But I enjoy talking to him and they are very pleasant and the gas is significantly cheaper for 93 octane. So I go there often. I DD my cars and beat on them whenever I can and they're perfectly fine.

[ST1LE]

Originally Posted by ember1205

Yeah, that seems to be sort of how I'm leaning with this as well. The general consensus I am finding around a few things seem to be:

- The current generation LT1 overall runs cleaner than previous iterations of the DI engines
- Top Tier gas has better quality and concentration of detergents
- DI engines tend to suffer from buildup on the back side of the valves which is what Top Tier gas is implied to help with, but gasoline never touches that area which is why the buildup occurs in the first place (it doesn't regularly get washed off).. So.. Huh?

As I mentioned, generally regular use of Top Tier gas is ok by me because Costco is on that list and it's the cheapest fuel around (and relatively accessible for me). I'm just curious about the possible impacts of having to mix a tank in here and there from BJ's when I simply can't get to Costco...

"Top Tier" is the same quality detergents, it is just a higher concentration. Typically 2.5x the standard dose of 'generic' additive. Still stands to reason that more detergents is better, even though the detergents themselves are the exact same.

Originally Posted by dpevans

I have been told in the past that all gas, diesel, and other fuel products are stuffed into a pipeline and when you purchase a "gas" product you get what comes out and there is no guarantee of where that gas was produced. I believe the definition of top tier is to purchase from a reputable dealer. So unless you live near a refinery you're getting what every they dump in the pipeline. Some upcharge for mixing in additives at the terminal before delivery but other than that it's all the same gas.

This is 100% correct, it is all the exact same gas. That said, ALL gasoline delivered to a gas station must contain the same 'minimum' amounts of gasoline, ethanol, and additive in order for it to meet federal specification requirements.

Originally Posted by Nothing like an SS

I know here on Long Island, all of the stations get refilled from the same distributor, so, brand be damned, they are all the same

Not true. Additives are brand specific, and are certainly not the same. I personally get better gas mileage from Chevron with Techron than I do Shell or Exxon gas. I work for one of those three, and Chevron is not one of them.

Originally Posted by ember1205

Top Tier Detergent Gasoline specifically refers to the concentration of additives in the fuel. Every fuel company sends a truck to the port to fill up and they all get the same fuel. The difference is determined by the quality and amount of specific detergents that are dumped into the tanker truck during the filling process.

Now it's perfect.

Originally Posted by SSDan

My son is a petroleum engineer and has explained gasoline refining to me. All gas is refined to the same federal standards and only two octanes are produced on the east coast - 87 & 93. Other octanes such as 89 and 91 are just blends of 87 and 93.

Yup, we call those "Mid-Grade", and it actually pumps both 87 and 93 in to the truck at the same time with two loading arms, pretty cool really.

The additives are added into the tanker at the point of fill at the refinery. Top tier companies each use their own proprietary blend of additives. Some non top tier stations use some additives and the El Cheapo stations use none.

Federal regulation requires all gasoline contains minimum amounts of additive.

So Ember has the straight scoop for the what and how of top tier.

Ember - I would say that the occasional use of non top tier is fine. Just keep using that Costco gas as much as possible.

For what it is worth, if I owned a Camaro or premium V8 I would avoid unbranded gas stations as much as possible.

A few times here and there will make no difference at all, but generic additive is inferior to all branded(Shell, Chevron, Exxon) additives.

Again, I use Chevron due to superior mileage in my experience.

[ember1205]

Originally Posted by ST1LE

"Top Tier" is the same quality detergents, it is just a higher concentration. Typically 2.5x the standard dose of 'generic' additive. Still stands to reason that more detergents is better, even though the detergents themselves are the exact same.

There is a requirement for both WHICH detergents get used AND how much. From their page:

All gasoline grades must be treated with an approved TOP TIER™ Detergent Gasoline additive at the correct concentration.

[ST1LE]

Originally Posted by ember1205

There is a requirement for both WHICH detergents get used AND how much. From their page:

All gasoline grades must be treated with an approved TOP TIER™ Detergent Gasoline additive at the correct concentration.

Exactly. Gasoline specifications are very strict. The point is that the all 'generic' additive is the same, including Top Tier. Terminals have one type of generic additive on hand at any given time, never more than one. That is the same additive used for normal gasoline and Top Tier.

[ember1205]

Originally Posted by ST1LE

Exactly. Gasoline specifications are very strict. The point is that the all 'generic' additive is the same, including Top Tier. Terminals have one type of generic additive on hand at any given time, never more than one. That is the same additive used for normal gasoline and Top Tier.

Additives are controlled by the brand, not the terminals. The terminals only dispense the fuel into the trucks.

At least, that's how it has been explained to me.

[ST1LE]

Originally Posted by ember1205

Additives are controlled by the brand, not the terminals. The terminals only dispense the fuel into the trucks.

At least, that's how it has been explained to me.

Yup, and you are not wrong ember. When is comes to a company's 'branded' additive, that is indeed sent to the terminal by the Brand.

There are typically two types of additive at a terminal. Branded additive controlled by the brand, and generic additive that is bought and offered by the terminal for its unbranded companies.

For example. The company I work for is a tenant in a Brooklyn terminal. At that terminal my company loads trucks injected with its Proprietary Branded additive, and those trucks go straight to our branded gas stations. For this step we pay the terminal an injection fee only, since the additive is ours. We also load trucks injected with the generic additive at the terminal, and those trucks go to Costco, Sam's, Albertsons, Quicktrip, etc. For that, we pay the terminal an injection fee AND a fee for the generic additive we purchased from the terminal.

Top Tier is a HIGHER injection rate of the Terminal's Generic Additive, and that injection rate is also determined by the Terminal(typically 2.5x-3.0x).

That is why when you buy non-branded gasoline, it is the same as any unbranded gasoline in that same market, as it came from the same terminal and has the same quality and quantity of additive chosen by the terminal. A Quicktrip will have the exact same recipes for its grades as the Costco that sits across the street from it. The only time the 'standard' changes is when you buy Branded Gasoline from one of the three Majors.

[ember1205]

Originally Posted by ST1LE

Yup, and you are not wrong ember. When is comes to a company's 'branded' additive, that is indeed sent to the terminal by the Brand.

There are typically two types of additive at a terminal. Branded additive controlled by the brand, and generic additive that is bought and offered by the terminal for its unbranded companies.

For example. The company I work for is a tenant in a Brooklyn terminal. At that terminal my company loads trucks injected with its Proprietary Branded additive, and those trucks go straight to our branded gas stations. For this step we pay the terminal an injection fee only, since the additive is ours. We also load trucks injected with the generic additive at the terminal, and those trucks go to Costco, Sam's, Albertsons, Quicktrip, etc. For that, we pay the terminal an injection fee AND a fee for the generic additive we purchased from the terminal.

Top Tier is a HIGHER injection rate of the Terminal's Generic Additive, and that injection rate is also determined by the Terminal(typically 2.5x-3.0x).

That is why when you buy non-branded gasoline, it is the same as any unbranded gasoline in that same market, as it came from the same terminal and has the same quality and quantity of additive chosen by the terminal. A Quicktrip will have the exact same recipes for its grades as the Costco that sits across the street from it. The only time the 'standard' changes is when you buy Branded Gasoline from one of the three Majors.

There are, effectively, three categories of gasoline:

- Those that opt for additives offered by the terminal. These will all be "the same as each other" because they are the exact same fuel with the exact same additives at the exact same ratios / amounts.

- Those that opt for their own additives but which do not meet Top Tier classification. These may or may not be the same as others within this category, depending on whether the additives are the same or not.

- Those that opt for their own additives and DO meet Top Tier classification. These may or may not be the same as others within this category, depending on whether the additives are the same or not.

Again, Top Tier requires specific additives in specific quantities to achieve the classification. It does not require a specific BLEND of additives, so brands are free to include things that aren't required so long as they are not on the prohibited list of additives. Your examples essentially imply that all Top Tier gas is the same, and all non-Top Tier gas is the same. This isn't accurate.

[Seniorrs]

[QUOTE=NA18CamaroSS;10997187]When I was working for a tuner in southern California, the only gas we had knock issues with was Shell. I had a built 11.5:1 VTEC motor in my Type-R and it was tuned to a tee on 91. I filled up at a Shell station and the car started knocking; I thought that perhaps they had pumped 89 or 87 into the 91 tank. Then, whenever we had a car knocking more than usual or making less power than expected, we started finding that the common issue was Shell gasoline. Forced induction Mini's that made less than expected power always turned out to be running Shell.
Running E85 (78-80 % ethanol) in my Camaro so the brand of gasoline available in my area is moot.[/QUOTE. I agree, don't like Shell gas either.

[ST1LE]

Originally Posted by ember1205

There are, effectively, three categories of gasoline:

- Those that opt for additives offered by the terminal. These will all be "the same as each other" because they are the exact same fuel with the exact same additives at the exact same ratios / amounts.

- Those that opt for their own additives but which do not meet Top Tier classification. These may or may not be the same as others within this category, depending on whether the additives are the same or not.

- Those that opt for their own additives and DO meet Top Tier classification. These may or may not be the same as others within this category, depending on whether the additives are the same or not.

Again, Top Tier requires specific additives in specific quantities to achieve the classification. It does not require a specific BLEND of additives, so brands are free to include things that aren't required so long as they are not on the prohibited list of additives. Your examples essentially imply that all Top Tier gas is the same, and all non-Top Tier gas is the same. This isn't accurate.

I would be interested to see examples of your second classification. I have not found a single branded additive that does not meet Top Tier.

[chevybill]

Does anyone know where Kroger and Sam's club gas is sourced?

I use these two in my daily driver. Camaro usually get shell premium.