['ol Pinion head]

Following is a response on the Net, question posed on quota.com

Ryan Carlyle, BSChe, engineer at an oil company
Answered 9 years ago.....
Originally Answered: What happens when tolulene is added to the gasoline in a car?

"Tolulene is one of the higher-value molecules already in use in many gasoline
Blends. The main benefit is that it's an octane booster that does not dilute the
energy content of gasoline like ethanol does. It's a C7 aromatic molecule, which
means it contains a lot of energy and vaporizes easily, but not so easily that it's an
air pollutant like lighter benzene (C6 aromatic) and butane (C4) molecules,
which percolate out of unleaded gas tanks and contribute to smog.

The tricky thing about adding aromatics is that the total quantity in your fuel
shouldn't exceed about 30%, which is the sum of all the benzene, toluene, and
xylene put together. Many regular gasoline blends already contain significant
amounts of aromatics -- up to 30% -- so there's no simple way to tell how much
more you can safely add. as it happens, the higher quality gasoline blends (which
supposedly includes Shell and Chevron gas but don't quote me on that) already
contain a lot of toluene and xylene. Adding toluene is more likely to improve low-
octane gan than high-octane gas.

A rule of thumb floating around the Internet is that you can safely add 10% toluene
to your gas without causing nine issues. So that would increase your 93 octane
gas to (93 * .9) + (114 * .1) = 95.1 octane...."

Not including his last paragraph as he just warns about buying higher octane fuel that's not needed...

Noted 3 paragraphs above it clearly states, how does one know how much of the these aromatics are in the particular (EPA region required) blend of unleaded 93 octane fuel? I ran into this threshold 30 years ago with xylene content octane boosters (tall can of Super104). I'm sure Commiefornia has multiple different regional required blends of each octane fuel to meet EPA attainment (AZ had the most, at least 7-8 years ago). Thus the blends will differ to a degree across the state & even in the same region.

Mixing example wise, one would need to take 1.8 gallons of toluene & add it to 18 gals of 93 octane unlead to raise the pump octane to the above 95.1 pump octane on near 20 gals of fuel. To me it makes little sense to pay through the nose for 18 gals of 93 octane pump gas then add $20-40 expense of tolulene. Building a cast iron headed street engine for slightly lower compression makes one H of a lot more sense.

[Carousel72TRed]

If adding 2 gallons of Toluene to 20 gallons of 93 octane gas only raises the octane to 95 from 93 it may make more sense for me to just grin and bear it and get the 100 octane gas at $10 a gallon. from the one station that has it in my area. Formulabruce and OPH do you know if Xylene is as good or nearly as good as an alternative to Toluene? Looking on line it is half or more as expensive as Toluene.

Carousel72TRed

[Baron Von Zeppelin]

When GTO's were new cars , the recommended octane rating for them was 100.
That was using the old octane rating method.
Using the new method octane rating to convert , todays 93 is right about equal to - or just shy - of the old 100 .

Somewhere on here it was researched in the past , about that ^ .

Not all areas offer 93 at the pumps, some stop at 91 .
It could be that you only need a couple more full points of octane for your car to be in the happy zone, over what you are buying at the pumps.

Another (probably better) option (especially in California) to give a try is blending your local premium with the $10/100 octane. Go with whatever amount of blend would put you in the same price range per gallon overall as using a $25 gal of Toluene with 10 gals of premium.

Do the math using your available prices , and start with that amount of blend.

Is your local Premium 91 octane - or is it 93 octane ?
And how much is it per gallon currently ?
In my area - 93 octane is currently $3.70-3.75 (alcohol blend)

Your car will not need 100 octane using todays octane rating method.
But you probably do need 93-95 zone

[Carousel72TRed]

Thank you Baron,

I did not know today's octane rating calculations are different than yesteryear's.

Carousel72TRed

[Baron Von Zeppelin]

Originally Posted by Baron Von Zeppelin

When GTO's were new cars , the recommended octane rating for them was 100.

edit :
When 64-70 GTO's were new cars ...

[Carousel72TRed]

And here in California 91 octane unleaded is the only premium pump gas available in my area (besides the $10 a gallon 100 octane gas0. As you are probably aware gas prices here in California are generally 75 cents to a dollar a gallon higher than what you probably pay. 91 octane unleaded runs around $4.75-$5.00 a gallon out here. (OUCH) and that's at Costco which is the least expensive place for gas generally.

[Baron Von Zeppelin]

Lets go with round figures to make it easier (for me) and pretend you could get TOL for $25 a Gal at the local ACE Hdwr nearby.

10x gals 91* @ $5 = $50
1x gal TOL @ $25 = $25
= $75 for 11 gals of juice of approx 93 Octane

7x gals 91* @ $5 = $35
4x gals 100* @ $10 = $40
= $75 for 11 gals of juice

Now , who wants to find the correct scientific formula
to see what the result of that 7x/91 : 4x/100 blend would equal in octane .
maybe 93 or 94 ?

Probably about a wash - but no witchcraft
and no hassle sourcing TOL

[Formulajones]

This is why I stopped monkeying around with that stuff decades ago. It was getting too costly and a real pain in the a$$ to mix all the time, especially for those of us that actually drive our cars frequently and for a couple hundred miles from home.

Better off just building the engine to run on this piss poor gas we have available. No reason you can't make 500-600 and even 700hp on the cat pea at the pump and run perfectly fine. I've been successful at it for 3 decades now.

[Carousel72TRed]

Thanks Baron,

For now I am going to start out with a 50/50 mix of 91 and 100 and since I don't drive my GTO a real lot (at least this year anyway) I will see how the car runs on this.

[jhein]

I'm just gonna keep using the Torco Accelerator which takes my 91 octane to 95 in one easy step.

[Carousel72TRed]

Hi jhein,

I just checked out their website and here is another option for me (maybe if California allows this product to be shipped to me). The thing I like is they give you the gallons, various starting octane gas values and the amount needed to attain the octane level you desire and at $150 a case that's $25 a bottle.

Carousel72TRed

[dataway]

Just today I picked up two gallons of Toluene at ACE for $23/gal. And I'm in NY, so if it's sold here it's probably sold in at least 48 other states.

Plenty of non-ethanol 93 octane around here. I figure a gallon of Toluene max in a tank full would get me into the ball park where I wouldn't have problems with my 9.9:1 iron head with an 068 cam.

Or just use the Torco if it works.

[70TA-RAIII]

I like the idea of the 50/50 mix of the 91 and 100 no-lead. Quick and convenient.

John

[Carousel72TRed]

Hi Dataway,

There is no 93 octane non-ethanol gas around here where I'm at. And my GTO has 68 16 heads and the last time I did a compression check I was pushing 210 in every cylinder except #7 (rear driver side) which was 185 and that means I'm at 10.75 compression. I need to run octane boost but the question is how much and I will find that out before long.

Carousel72TRed (Grew up near Syracuse)

[Formulabruce]

IMHO you need to experiment, and watch the heat.
Many tests have shown that e-10 can be up to 15% alcohol. Plenty of proof on you tube..
This can mess up trying to actually get the math chemistry exact.
Also dynamic compression is almost Always lower than "Static" compression so the mountain you are climbing may not be as steep as the "math" numbers would indicate.

[johnta1]

who wants to find the correct scientific formula

Octane Calculator



Xylol is not as good as toluene as a gas additive.
Toluene is very susceptible to static ignition. Have to be very careful pouring it.

I personally would use E85 if I needed the octane boost.

[dataway]

Originally Posted by Carousel72TRed

Hi Dataway,

There is no 93 octane non-ethanol gas around here where I'm at. And my GTO has 68 16 heads and the last time I did a compression check I was pushing 210 in every cylinder except #7 (rear driver side) which was 185 and that means I'm at 10.75 compression. I need to run octane boost but the question is how much and I will find that out before long.

Carousel72TRed (Grew up near Syracuse)

Did you check: https://www.pure-gas.org/ for a station near you?

If you use the Torco stuff ... let us know how it works.

[Sirrotica]

Originally Posted by 'ol Pinion head

Building a cast iron headed street engine for slightly lower compression makes one H of a lot more sense.

This ^^^^^^^^^^^^^^^

I drove a fuel tanker for a couple years, and have seen, and talked to the guys that blend the fuel for it's intended use. There is a lot more to blending fuels than the average layperson knows.

The gasoline is held in tanks at the racks just as it comes from the pipeline that supplies the racks from the refineries. It is segregated by specific gravity to begin with, but they have a helluva lot of equipment that determines what the specific gravity is, what the octane is of that fuel, and then they make adjustments to the base fuel to get it where they want it.

It's all computerized when they do the blending, and takes into account what the base fuel consists of as it comes from the refineries, they don't always get the same consistency from the pipelines that carry it to the racks.

One thing most don't know is one pipeline can carry many different fuel blends. sometimes the fuel is separated, but most times you can have different fuels coming out of the same pipe , they run it into one tank until the specific gravity changes, then they switch to a different tank. That switchover blend is a combination of 2 different products that are effectively blended at the beginning and end of a product change into the pipeline. they obviously don't waste that product, it gets used somewhere, they call that unspecific product, slop, but it still gets used.

You might be able to see why blending fuels at home with high aromatics can be just a crap shoot, because you really have no idea what came out of a service station pump, and what blending they did to get it within spec.

When the order for the fuel that is to be loaded on tankers, only then is the ethanol added to further adjust the base fuel for what it's end product is to be

The ethanol is also held in tanks and only blended as it goes into the tanker, most likely because the ethanol begins degrading as soon as it is exposed to humidity in the air. Ethanol is made and used quickly, it doesn't sit in tanks for any length of time at all, compared to petroleum based fuels.

At some loading racks we used to be able to see what percentage of ethanol got blended to make the end product, it varied a lot all depending upon what octane the petroleum fuel started out with.

[bird72]

My HO with forged pistons is appx. 10 to 1. I have been running 91 octane no ethanol here in NW Montana, runs fine. So I am scheming on relocate and bought property in remote SW New Mexico. So was just down there and scoped out the gas pumps in the little village in the area. I was sure the premium would be ethanol. Was kind of surprised to find no premium at either of two pump locations in town. Regular and Diesel only at both. So asked and found out premium was 32 miles away down the road (with ethanol). So to further depress myself, I just checked online of closest no ethanol. That is only 115 miles away in Show Low AZ! So I guess if my bird ever makes it down there, I will get to transport gas, if I want no ethanol. Or burn 5 or 6 gallons to drive it to the ethanol (premium) place. Really hate to run ethanol, it has never seen it in use.

[jhein]

Originally Posted by bird72

My HO with forged pistons is appx. 10 to 1. I have been running 91 octane no ethanol here in NW Montana, runs fine. So I am scheming on relocate and bought property in remote SW New Mexico. So was just down there and scoped out the gas pumps in the little village in the area. I was sure the premium would be ethanol. Was kind of surprised to find no premium at either of two pump locations in town. Regular and Diesel only at both. So asked and found out premium was 32 miles away down the road (with ethanol). So to further depress myself, I just checked online of closest no ethanol. That is only 115 miles away in Show Low AZ! So I guess if my bird ever makes it down there, I will get to transport gas, if I want no ethanol. Or burn 5 or 6 gallons to drive it to the ethanol (premium) place. Really hate to run ethanol, it has never seen it in use.

You could always get your own tank and have fuel delivered to you. I have a friend who does that and I'm considering it myself.