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Adding Toluene for more octane

Excellent article in Alkydigger web site about adding toluene to gasoline for more octane:

https://www.alkydigger.net/TechInfo/raising-the-octane-and-reduced-plug-fouling-with-toluene-added-to-gasoline/

The Surfers top fuel dragster team in the ’60s was known to explore toluene with nitromethane for their racing fuel.

However different fuel mixtures, especially those with nitromethane, are touchy.  They should be avoided without expert consultation!

The Alkydigger article indicates toluene has limitations as well.

Running 50% Nitro Amounts

Adding nitro to a methanol racing engine is an easy way to make more power.  Assuming a 50% mixture by weight, not volume.  FYI: A 50% mixture by volume is 59% by weight which is a different setup.

NORMALLY ASPIRATED

The enrichment for a normally aspirated racing engine with moderate compression ratio (around 10.8 to 1) is around 55% more fuel than the amount for straight methanol.

The added power from the nitro with the correct amount of fuel to the NA engine would be close to 60% over the straight methanol power.

BLOWN (SUPERCHARGED)

The enrichment for a supercharged racing engine with moderate compression ratio (around 8 to 1) is around twice the amount of fuel over straight methanol. Continue reading

Fuel Enrichment for Methanol Racing Engines

The enrichment for a normally aspirated racing engine on methanol is around 15% excess fuel over the stoichiometric (best burn) amount.

The enrichment for a supercharged racing engine on methanol with high compression ratio wedge head is around 65% excess fuel over the stoichiometric (best burn) amount.

The enrichment for a supercharged racing engine on methanol with high compression ratio Hemi head is around 85% excess fuel over the stoichiometric (best burn) amount.