Why do you assume the pump label tells the truth. The pump labels tell you the AVERAGE of two dissimiliar octane test done at the refinery. It cost the refinery 5 cents more per gallon or a penny a blended octane point to produce in massive quanities!

For driving the Motor Octane test is more critical and more expensive per point, yet you cannot find this out except by driving the product in your car.There is the little known SENSITIVITY INDEX for each engine model this varies with air temperature!

Some 94 Averages are boosted with worthless and cheaper Research octane points [for Marketing] some 91 Averages have higher Motor Octane points.

Refineries make two versions usually for each market [regional EPA zone] regular and premium. Some how the same premium gets called 91,92,93,94 octane based on brand marketing.

Many states sample gasoline at stations to make sure Premium is premium but their analysers are only accurate enough to determine that the premium is better than regular not by how much. Mid grades are usually just a 50/50 mixture of the two supplied forms.
How one state tests up to 3X per year*:
http://www.americancityandcounty.com...w_mexico_uses/

* Testing 3 days per year leaves lots of time for individual stations to accept less than standard grades! They call their distributor when tested so they chart the tester route........not random testing I'm sure...........the State may even call ahead or send a letter with testing schedule. Do State employees work on weekends?

Decent read:
http://www.nsxprime.com/FAQ/Miscella...lAdditives.htm

 

http://www.3dman.com/Ducky/Hot_fuel.htm

Here's a link with some locations of race gas in California. I had a link to a bigger list but it seems the link is no longer any good.

 

91 here in OK. $1.929 gallon. (Shell) Every other weekend I do treat myself to a full tank of 101 octane (Texaco), which is currently $3.699 gallon. (A bit pricey, but burn's really well with my Nitrous).



B. Silver| 20" Iforged - Flux| Z-Tube | 6 Wire GroundingGear | Borla | "Custom" Stereo - JL/Focal/Clarion \ Zex 100 Shot - Purge Light |Crawford Cats / Brake Pro's Slotted Rotors/ Hawk Pads

 

<blockquote><font class="small">In reply to:</font><hr>

use paint thinner.the good stuff. it works safely..one gallon to 10 gallons of gas. raises octan 4 or 5 points

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The term paint thinner is a meaningless term. There are dozens of solvents used to thin paint. Assuming that you mean Mineral Spirits or VM&P, the quality will vary from brand to brand. IMHO this is a BAD IDEA.

 

Use Xylene or Toluene (Paint Thinners), at a 4:1 ratio. 4 gal premium to 1 gal xylene. For every 1 gal of xylene, use 1oz of Marvel Mystery Oil. do a search for it on Turbobuick.com and gnttype.org. It's hard to tell any difference in our cars. But you can tell the difference in a Forced Inducted car. Xylene is an ingredient that off the shelf Octane Boosters use.


| Hawaii International Race School | Formula Hawaii | Drift Session | Mid Pac Road Racing Association |

 

My dad was a chemist and used toluene/toluol as an octane booster, because that's essentially what it is. It does safely boost the octane, though you probably won't notice it too much unless you happen to get a tank of low octane crappy gas, and then who really knows (per Z45's post). Higher octane makes a noticeable difference on the FI cars.

'04 6MT coupe