87 octane

[Tommm]

Originally Posted by gjm120

By quality of the additive pack of course I meant the quality x qty of the additives. Obviously a ml of very good additive can be better than a litre of poor additive. Just for reference, the typical additive injection rate at the truck loading rack is only about 100ppm.

From way back in my early working life, I know premium had a higher additive dose than lower grades for most brands. Don't really know, but, I would guess currently that is still the case.

Point of interest is that Costco mogas may have additive added at the pump
http://www.neiwpcc.org/tanks2013old/...13_Tuesday.pdf

So how does one tell the difference between different brands of top tier? How does one do a blind taste test with gasoline? Each TV gasoline ad tells me theirs is better than the competitions.

[gjm120]

Originally Posted by Tommm

So how does one tell the difference between different brands of top tier? How does one do a blind taste test with gasoline? Each TV gasoline ad tells me theirs is better than the competitions.

Eenie, meenie, minie, mo...

Seriously, hard to say. Like I said earlier, I've read a good bit that the PEA in Chevron/Texaco gasolines is 'special'. For all I know, other Top Tier retailers may have PEA in their additive pack. I think Shell's additive package is very good. Phillips and Conoco (same gaso) advertise that they have somewhat more additive than is needed to meet Top Tier. I would advise to stick with TT gasoline most of the time. You've seen how much crud can end up on direct injection engines because those valves don't get a splash of detergent. Not using a good detergent gasoline will push the N52 in that direction.

I like running premium but don't like the huge differential at the supermajors so often use whatever TT is reasonable.

[Tommm]

Originally Posted by gjm120

Eenie, meenie, minie, mo...

Seriously, hard to say. Like I said earlier, I've read a good bit that the PEA in Chevron/Texaco gasolines is 'special'. For all I know, other Top Tier retailers may have PEA in their additive pack. I think Shell's additive package is very good. Phillips and Conoco (same gaso) advertise that they have somewhat more additive than is needed to meet Top Tier. I would advise to stick with TT gasoline most of the time. You've seen how much crud can end up on direct injection engines because those valves don't get a splash of detergent. Not using a good detergent gasoline will push the N52 in that direction.
I like running premium but don't like the huge differential at the supermajors so often use whatever TT is reasonable.

Eeenie Meenie works. I like the dinosaur logo so I go with Sinclair mid grade on the BMWs, premium for a tank before a driving event. I get a dime off shell every week or two because of the Kroger rewards so I use Shell regular in the S89 V8 when it doesn't get the dinosaur. My wife likes to fill up when she does the grocery shopping so she puts the Kroger/Loaf n Jug regular in her Volvo V8 with her rewards. Kroger was Top Tier until a while ago. I contacted HQ and got a nice boilerplate response that their fuel is top quality with detergent. It may be the same stuff without paying for the label.

[JimD]

I read an interesting piece on the "oil guy" site several years ago. The author claimed to have used the same brand of gas for 10K miles or more and then torn down the engine several times. He noticed deposits regardless of the brand of gas. But he then argued that switching brands sometimes may help wash away the deposits from the brand you usually use. MIGHT be true. I think of it each time I uses something other than Shell, my normal choice. Maybe it actually helps to use something else occasionally.

My old SUV got literally whatever was cheapest when I had it and my son is doing the same (except he seems to like to buy food at the gas station and that enters his decision making too). Around 200K now with less issues than my n52 (which has been pretty good).

[Rmtt]

Where I go to dyno tune my Corvette and my previous ones, you could see differences in 93 octane between different gas stations while on the dyno by watching the "WideBand" sensor data and how it would affect timing and fuel tables.

Not sure how tuning programs with BMW work, but HPTuners would let you watch live data as you were spinning the engine up.

[Olgeezer1]

Nope. After spending lots on upgrades I'm not going to cheap out now. Also here, Top Tier Shell91 and Esso91 are ethanol free so pure gasoline without corrosive ethanol.

[chris_flies]

Originally Posted by Olgeezer1

Nope. After spending lots on upgrades I'm not going to cheap out now. Also here, Top Tier Shell91 and Esso91 are ethanol free so pure gasoline without corrosive ethanol.

The fuel systems in these cars were designed with ethanol in mind. These are not pre-90's cars that have pure rubber lines that will dissolve and steel fuel tanks that will rust into oblivion. Plus, ethanol burns cooler than gasoline, so you're likely doing more harm than good with the Alumasil cylinder lining...

TL;DR Version: On a scale of Honda Civic to LaFerrari, these cars are a Honda Civic. Designed for the lowest common denominator of the global population (and that's pretty damn low nowadays).

My car's got 200k miles on it, and has received no special treatment, and it's going perfectly strong. Probably better than most of these cars at 50k if I do say so myself...

[JimD]

I do not think ethanol fuel is an issue for modern cars, PROVIDED, they do not sit for long periods. There is a you tuber with the handle "Project Farm" that did an interesting comparison of the properties of pure gasoline and ethanol fuel. The big issue is that alcohol really likes to absorb moisture from the air. Once it does that, bad things happen to carbs and other small openings in the fuel system. I probably need to clean the carbs on my old fishing boat right now due to using ethanol fuel and it sitting for months at a time (I like my pontoon better). I've had to clean them several times.

If you put your car in storage, it would be a good idea to fill it with non-ethanol gas. A full gas tank leaves less air to contribute moisture and the pure gas will be less likely to break down.

But if you will burn it within days, ethanol will not harm a modern car. The longer the storage, the more likely an issue.

[pgk500]

Originally Posted by mconrad1776

Any else fill up their car with 87 octane?

Yup.

[pgk500]

Originally Posted by JimVonBaden

Yes, regularly. I really can't tell the difference.

Agreed. Same here !

[blue135]

Well, I am sticking with 93.