Octane Booster

[Nantucket427]

The information on the motor recommends a 50/50 mixture of regular gas and racing fuel or an Octane Booster. What works and were do you get it?

[Spoony]

I use a bottle of Outlaw Octane boost in every tank. It made a big difference in how my motor runs. I get it at Autozone, it's not cheap, but if you have to ask you can't afford it right??

[Mr.Fixit]

find a sunoco distributor in your area. buy leaded race gas, and mix with pump premium. average the octane ratings by volume

[427 S/O]

Or...you can pick up 5 gal. of toluene and mix 10 gal., 2T-8G. It's what the oil companies use.

[George Snyder]

Nantucket,
Mr. Fix it is correct on the method to determine what octane you are using. 93 + 112 = 102.5.

Boy,
I sure hope you do not plan on running this engine on the street? For one thing the cost would be phenomenal! It won't take too many long cruises until the only thing you will find in the bottom of your pockets will be lint!

427 S/O,
I have never tried home brews, but it appears that there is a little more to it than what you mentioned. The race gas as an additive is a whole lot cheaper and safer.

http://www.vtr.org/maintain/gasoline-octane.html

Ps. The prices for Tolene are extremely understated.
Bud

[427 S/O]

George, like I said the oil companies use
toluene. How do you think 87 get's bumped to 93, your also wrong on the costs, in my area 5 gal. of toluene is $23.00 and race gas is $4.55 gal. 93 is $1.50...

[George Snyder]

Perry,
I agree 100% that Toluene is the major ingredient that is used to raise the octane in gasoline. I am pretty sure that it is not the sole ingredient added.

If you read the end of the article you would have seen the formula that a popular octane boost products manufacturer uses. Tolune, mineral spirits, & transmission fluid.

I do not understand your statement that i was wrong about the race gas being cheaper?
Toluene is $23 divided by 5 gallon is $4.60
Race Gas is $4.55 per gallon.
The cost of the 93 pump gas has nothing to do with the cost equation, as it is used in both cases.

If you add the other ingredients as is suggested the toluene cost will go even more than the $.05 you started with.

Another home made mixture I have seen used is 1 gal toluene + 1 qt mineral spirits+ 4 oz Marvel Mystery Oil.

The one plus toluene has over race gas is 114 Vs. 100 or 112.

Last but not least is the "Safety Issue". If you read the Warning Label, it states that when handling toluene that you use a Vapor-particulate respirator (NIOSH approved).

For the record, I am not tring to break your b*lls. I am in the Fire Supression Business and have seen first hand Toluene Fires. It is Dangerious stuff. About the best way to extinguish it is using A FFF Foam in a 3% concentration applied on top of it.

I would just hate to see a flock of our members run out and start playing with toluene, not knowing all the facts. Hell the Race gas is lethal enough!
Bud

[rlearp]

Toluene is not that expensive from Fisher, VWR, or other suppliers (in bulk). You do not need UV/vis or HPLC grade, you just need basic toluene. I've bought lots of the stuff and do so a couple of cases at a time.

Handling is not particularily difficult. I'm a chemist and respect it, but it isn't too bad. Don't expose it to your skin, take precautions against vapor inhalation (just add it to the tank outside, not in closed quarters), and you'll be fine. Of course, like other chemicals we like to burn in combustion engines stay away from sparks and sources of ignition!

Toluene used to be a fairly common solvent in the organic labs I used to teach and work in, but it seems to not be the case any longer.

I use it as an additive to gas for my Lotus Turbo since it runs a lot of boost and needs a high octance fuel to prevent knocking (20lbs+). I've not got the 40 together yet, but that motor is 11:1 so it will need some good gas too.

Ron

[terry lee]

For years I used to use Toluene to clean the board cover on my drawing boards; it worked wonders. I remember reading something about not using in enclosed spaces, but none of my co-workers ever complained. Got a little light headed myself afew times, but it sure smelt good.
Now another use?

TL

[427 S/O]

My comments/knowledge about toluene came from the head of weights and measures for the state of Georgia, he suggested a mix of 2T and 8G for ten gallons and additivies are not necessary. Toluene being 117 octane will go further than 104 racing gas (the cost). I'm not dependent on this mix, just like to play once in a while....

[Nantucket427]

Thank you all for the Chemistry Lesson, I will avoid Toluene at all cost.
I have seen many different boosters that you simply add to your gas tank. Which one has anyone used and which ones work best?

[427 S/O]

Nantucket, the commercial octane boosters are a rip off, when they say it will raise the octane by _ points, their not telling the whole truth. If they say 3 points, they mean From 93 to 93.3, no way will this produce any noticeable
improvement.

[rlearp]

Nantucket,

There is nothing wrong with toluene, treat it just like any other chemical and you'll be fine. I would not avoid it at all as it is one of the cheapest ways to accomplish what you need.

I'm sure you've handled nastier stuff in the past and probably didn't notice it. Gasoline has a MSDS that is quite large but causes no problems for most of the folks on the planet.

Ron

[Mr.Fixit]

You can buy race gas that is more than 100 octane, you can get 114 or 116.

[Nantucket427]

This is exactly what the engine builder said; We recommend mixing the fuel with some sort of octane boost or running a 50/50 mix with race fuel.
How do I figure out the octane that you would get from this fixture? Then how much toluene would you use to get that results ?
Compression Ratio 10.25:1 total timing 36 degrees.

[Jmar]

I have 10:1 compression AL heads,36 degrees timing and run 94 pump gas. No detonation problems. I could have gone up to 10.5 easily. Iron heads will be a little different since they retain combustion heat. If your cam has enough duration/overlap, you will bleed off cylinder pressure at lower RPMs to reduce the chance of detonation. The lower RPM range with part throttle acceleration is where the older high compression engines would have detonation problems. If you use a cam that develops high cylinder pressure at low RPMS AND you have a higher static compression ratio, you may have detonation problems.

Does anybody have dyno #s to prove that these mixtures will improve performance? Has anybody compared the cost of these mixtures to other mechanical methods of adding power? If I weighed the cost of additives against a cam or a blower, I think that mechanical improvement would be more economical in the long haul.

Just my .02

[Mr.Fixit]

Expensive, high octane fuel DOES NOT make additional power. It is simply necessary when you have higher compression. Run just enough octane rating to have a stable flame travel, any more is simply wasting money. Changing your cam will not change your engine's octane requirement (except at very low engine speeds) adding a blower will.

[Carnut427]

Originally posted by Mr.Fixit


Changing your cam will not change your engine's octane requirement (except at very low engine speeds)

With all due respect, yes it will. Read this:
http://cochise.uia.net/pkelley2/DynamicCR.html

A long duration cam requires less octane than a 'normal' cam. The reason is that the intake valve remains open until the piston is part way up the cylinder on it's compression stroke. The engine cannot build compression at this time because it's not a closed cylinder. This is why the cam companies will tell you something to the effect of "requires 10:1 compression"; without this much static compression, the engine will not have enough "dynamic compression" to build any low end power. The term "dynamic compression", as used here, refers to the compression the engiine actually sees while running. There is a program on the above website you can download to figure it out. The website also gives a great explaination, which I've barely touched on.
Good Luck,

Dan

[Don]

Reference " The Idaho Corvette Page' , Corvette Articles, Gasoline Digest, " What you need to know about fuel for Corvettes and other high performance cars " written by Hib Halverson. Will answer some of the questions being asked.

In the 2nd section of the article is a chart for mixing 76 Competition 100 Racing Fuel with 76 High performance 91 Gas in various ratios to obtain the desired fuel mix.

Included on the site are articles that apply to any high performance autos

www.idavette.net

[captain]

Nantucket,
Which cobra did you buy? Which engine?
I remember you were at Carlyle looking.