How to increase gas octane

[Philip Procter]

I know there are lots of gas additives that raise octane, but they're
all really expensive for everyday use.

Anybody know what chemical and in what amount is needed to raise
octane from 93 R+M to, like 96?

The difference here between 89 and 93 is about 0.10$/gal. If I try to
do the same thing with octane boosters, the added cost would be closer
to 0.50$/gal. Meethinks somebody is getting rich, and I don't want to
help them.

 

[hippo]

I have been informed (by someone whose opinion appears to be reliable) that
10% ethanol will add nearly 2 points RON, so that's half way there & might
even do you (assuming you're starting from a no ethanol base & you can get
ethanol fuels where you are). I'm running 92 with ethanol instead of 95
where i am at the moment to test the theory!

 

[Ragnar]

I know there are lots of gas additives that raise octane, but they're
all really expensive for everyday use.

Anybody know what chemical and in what amount is needed to raise
octane from 93 R+M to, like 96?

The difference here between 89 and 93 is about 0.10$/gal. If I try to
do the same thing with octane boosters, the added cost would be closer
to 0.50$/gal. Meethinks somebody is getting rich, and I don't want to
help them.

I would suggest you Google for "toluene". Its a gas additive that you can
use to increase octane.

I haven't tried it and all I know about it is what I read, so take the
advice with caution. In other words, I'm not liable

 

[Nige]

I have been informed (by someone whose opinion appears to be reliable) that
10% ethanol will add nearly 2 points RON, so that's half way there & might
even do you (assuming you're starting from a no ethanol base & you can get
ethanol fuels where you are). I'm running 92 with ethanol instead of 95
where i am at the moment to test the theory!

I believe adding c stoff will increase the octane rating

 

[y_p_w]

I know there are lots of gas additives that raise octane, but they're
all really expensive for everyday use.

Anybody know what chemical and in what amount is needed to raise
octane from 93 R+M to, like 96?

The difference here between 89 and 93 is about 0.10$/gal. If I try to
do the same thing with octane boosters, the added cost would be closer
to 0.50$/gal. Meethinks somebody is getting rich, and I don't want to
help them.

Most of these thing only work in reasonably large quantities. A
12 oz bottle added to a 16 gallon tank isn't going to appreciably
increase octane, regardless of what the label says. Buying high
octane fuel will be cheaper than adding enough of this stuff to
match high octane fuel.

About the only thing that actually works is tetraethyl lead. A
few drops per gallon can actually raise the octane rating from
2 to 12 points. It can be purchased for off-road or marine use.
I wouldn't recommend it in any car with a catalytic converter or
O2 sensors - that would rule out any car sold in the US in the
past 20+ years.

 

[FNO]

I would suggest you Google for "toluene". Its a gas additive that you can
use to increase octane.

I haven't tried it and all I know about it is what I read, so take the
advice with caution. In other words, I'm not liable

Toluene is the recommended additive to increase octane ratings for unleaded
gas. However, the most common use of toluene is as a paint thinner. It is
expensive, it takes a fair bit of it to raise octane ratings from 93 to 96,
and the stuff is highly toxic; meaning it is difficult to handle safely.

Unless you are tuning the car for racing, I am not sure why anyone would
want to go much above 93 or 94 since even the STi only recommends 93; while
other turbo scoobies run fine on 91. Adding alcohol will increase the
octane rating, but because alcohol has less energy per litre than gas does,
it will not increase the power of the vehicle. It will prevent it from
retarding ignition so you can maximize the energy available in the fuel
though, and it will allow you to increase the boost pressure of the turbo,
but both at the expense of gas mileage.

 

[WRXtreme]

I have been informed (by someone whose opinion appears to be reliable) that
10% ethanol will add nearly 2 points RON, so that's half way there & might
even do you (assuming you're starting from a no ethanol base & you can get
ethanol fuels where you are). I'm running 92 with ethanol instead of 95
where i am at the moment to test the theory!

Ethanol burns too hot to be an effective fuel in turbocharged vehicles, keep
that in mind if you are utilizing a turbocharger.

 

[WRXtreme]

I would suggest you Google for "toluene". Its a gas additive that you can
use to increase octane.

I haven't tried it and all I know about it is what I read, so take the
advice with caution. In other words, I'm not liable

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

 

[2 Stroke]

Toluene is 114 octane (R+M). One gallon of toluene + 10 gallons of 91
octane will yield 11 gallons of 93 octane.

I've been using a gallon in every tankful for the last 18 months
without problem in my 03 WRX. Toluene is already present in "super"
unleaded, in concentrations that vary from ~10% to as high as 25% or
so. Concentrations are often higher in gasoline sold outside the U.S.

While it does improve gas mileage a bit, from a strictly economic
standpoint, its not cost effective. I use it because I like the
increased performance. ICI Paint stores sell it here for under 6
bucks a gallon.

=========================================

 

[Ragnar]

Toluene is 114 octane (R+M). One gallon of toluene + 10 gallons of 91
octane will yield 11 gallons of 93 octane.

I've been using a gallon in every tankful for the last 18 months
without problem in my 03 WRX. Toluene is already present in "super"
unleaded, in concentrations that vary from ~10% to as high as 25% or
so. Concentrations are often higher in gasoline sold outside the U.S.

While it does improve gas mileage a bit, from a strictly economic
standpoint, its not cost effective. I use it because I like the
increased performance. ICI Paint stores sell it here for under 6
bucks a gallon.

What if you ordered a 55 gallon drum from a chem supply warehouse? Should
amortize out to maybe $3 a gallon. I would get a handpump and keep the drum
waaaayyyyy out in my back yard.

 

[Edward Hayes]

Way out means about 100 yards if it explodes. Better yet bury it under 6
foot of dirt.

 

[Ragnar]

Way out means about 100 yards if it explodes. Better yet bury it under 6
foot of dirt.

Yeah, well my car in my garage is about 30 feet from my bedroom. Its as
likely (if not more so) to explode as a drum of toluene.

 

[y_p_w]

What if you ordered a 55 gallon drum from a chem supply warehouse? Should
amortize out to maybe $3 a gallon. I would get a handpump and keep the drum
waaaayyyyy out in my back yard.

Here's a place in upstate NY:

<http://www.senecaresearch.com/sc.shtml>

$175 for a 55 gallon drum. My guess is that you also have to pay
sale tax on this. Even if adding toluene is safe (sounds like it's
not likely to damage most engines/fuel systems), I have my concerns.
It might cut the concentration of detergents and other additives in
the fuel slightly. With a 55 gallon drum, I'd be worried that it
might also degrade in storage or the drum takes in moisture.

However - the price of premium unleaded in parts of California is
now about $2.50/gallon. The price of toluene isn't much more for
something that's used in relatively small quantities.

 

[Bill Sharpe]

Why bother?
My 2004 Forester runs fine on 87 octane gas -- even 85 octane as sold in
some western states.

Bill

I know there are lots of gas additives that raise octane, but they're
all really expensive for everyday use.

Anybody know what chemical and in what amount is needed to raise
octane from 93 R+M to, like 96?

The difference here between 89 and 93 is about 0.10$/gal. If I try to
do the same thing with octane boosters, the added cost would be closer
to 0.50$/gal. Meethinks somebody is getting rich, and I don't want to
help them.