Home Brew Octane Booster recipes - what have you got?

[af2]

Once upon a time, the addition of leaded fuel to unleaded fuel would raise the octane to a higher level than either individual component. Those days are now gone since the fuel components have changed and are much less sensitive to the addition of lead.

David, I would think they would be even more sensitive to lead.
The acetone has me wondering also.
I am not disagreeing but wondering instead.

[David Redszus]

Once upon a time, street fuels contained a substantial amount of aromatices (like xylene) which responded very well to the addition of lead. The same held true for certain oxygenates.

Both components have been reduced in pump gasolines so that the addition of lead makes much less difference than it used to do.

A small addition of lead (under .5%) does have a beneficial effect on valve recession with cast iron heads. Hardened seats are not affected.

Acetone is a great solvent. It wants to dissolve everything. Including your entire fuel system.

[SWR]

Acetone is a great solvent. It wants to dissolve everything. Including your entire fuel system.

Strangely, it doesn't seem to do so.. I have a friend who swears to the stuff, and he ran a liter of acetone in every 60-liter tank of gas he ever filled on his Volvo 240... we're talking over half a decade of fillups here. That car knocked like crazy at low and mid rpm's - told him to check and adjust the ignition to a lower value before he killed something but he refused saying the mileage would suffer - but with the stuff in the tank all that detonation was gone.

Sounds like a tall tale I know, but I rode with him once to get a bottle, and it knocked so hard on the inclines I cringed in the seat... he filled the bottle into the tank, we drove the same incline again, not a sound. Hadn't I seen (heard) it myself I would not have believed him for a second..

Maybe it slows down the burn, I don't know. But it does something.

[David Redszus]

Maybe it slows down the burn, I don't know. But it does something.

A slow burn would produce an increase in detonation.

Acetone does contain 27.5% oxygen, boils at 133F, has a heating value close to gasoline, does not have very high octane. One liter per 60 liters is about 0.0166 by volume. It is very hard to believe that 1.6% of anything can make much difference.

Maybe it just cleaned the crap out of his fuel filter.

[SWR]

Maybe it just cleaned the crap out of his fuel filter.

...or the flammability limits of his mixture was just 1% off..

[JBV-HEADS]

I've never seen just acetone hold nitro in suspension in race gas. It needs a polymer with it. I say this because I don't want anyone to blow an engine. I've never seen acetone harm anything in our race systems either. Good luck,

Joe

[Daygoslow]

Maybe it slows down the burn, I don't know. But it does something.

A slow burn would produce an increase in detonation.

forgive me if i am wrong but i thought higher octane fuels burned slower which is why they can handle the higher heat associated with higher compression without igniting? if it slowed down the burn wouldnt it help prevent detonation?

[David Redszus]

Maybe it slows down the burn, I don't know. But it does something.

A slow burn would produce an increase in detonation.

forgive me if i am wrong but i thought higher octane fuels burned slower which is why they can handle the higher heat associated with higher compression without igniting? if it slowed down the burn wouldnt it help prevent detonation?

If one were to dyno an engine using a low octane race fuel, and after noting torque and lambda values, were to add TEL to raise the octane, what would be the result? There would be absolutely no difference unless the engine was alread running in detonation.

Octane has NO affect on flame speed whatsoever. What octane actually does is lengthen the time during which the unburned end gas can resist autoignition. It buys some time to allow the flame front to burn the end gas before it can autoignite.

Flame speed is the combined result of laminar flame speed and chamber turbulence (usually squish velocity) which add together to determine how rapidly the flame will propagate across the chamber.

If two fuels had the same octane but were otherwise different in composition and properties, they would not burn the same.
If two fuels had the same composition and properties but were different in octane, they would burn the same as long as the limits of detonation are avoided.

[BGriff]

I should warn everyone that while I got all excited last year about how well toluene was running as a fuel, it attacks neoprene.
It swells it up and makes it soft.
The fuel pump in my F250 sounds like a sick bird sometimes.
I'm suprised it hasn't quit.
Lost a pickup tube in a chainsaw too when blended gas got used for mixing gas.

Several years ago when running NOS I had a reoccuring problem with the seat seals swelling in NOS fuel solenoids until they would not let fuel pass.
Now I'm wondering what component of the racing gasoline caused that.
I remember turbo blue caused the problem. I can't recall if the cheap Renegade gasoline caused it or not.

[JBV-HEADS]

Your problem with Turbo Blue is that there are vendors trying to cut costs. Since TB has so much die in it, they cut their costs by the following. They use 40% TB for color, 50% street gas for filler, and 10% methanol to keep the car from detonating. It is rampant in the racing world now because of the economy. It’s the methanol that is after the seals. If you have non oxygenated fuel you can check by pouring a baby bottle half full of race gas and then pour half of the bottle with distilled water. The line from the fuel/water separation better still be at the half full mark. If there is more water than half, it is ethanol from the street gas and methanol. The alcohols will phase separate to the water from the fuel. You don’t have real TB if this happens. Good luck,

Joe

[pdq67]

Kemco 130 Lead Supreme is real TEL!

It can raise octane like 92.0 to 96.0 instead of 92.0 to 92.6!!!

Otherwise, mix this up....

A gallon of Toluene;

A quart of Diesel; and

A pint of MMO or ATF.

I want to say that up to 30 percent of this will put you at 96 to 97 octane w/ unleaded as the base.

DO a WWW search on this b/c it WILL turn up.

pdq67

[JBV-HEADS]

I'm not even going to look that one up. Thats the hicks from the sticks, tire softener. Has been for years. Don't run it.

Joe

[pdq67]

Why? Toluene is the octane producer and the other stuff is for lube and cleanliness, if not mistaken.

Otherwise, run Kemco 130 Lead Supreme! Real TEL so be very careful handling it b/c it's poisonous.

Or set your engine up to run E85.

I don't know if anybody know's for sure what it's top CR is, so go from there. 17, maybe 18 to 1????

pdq67

[JBV-HEADS]

Toluene is one of the most used octane boosters out there. C16 has about 25 percent in it. Or close to that as it separated in that amount when tested. But the other things don't help matters and like I said, it is a very good tire softner for dirt track tires. Good luck,

Joe

[redsmokin57]

jbv heads, would this tyre softener receipe work for a stock rag or repo radial whitewall for drag racing,been looking for something the F.A.S.T racers might be using.
Cheers Steve