octane booster

[Mark75H]

what is the +/- percentage factor with the retail gas octane? When you purchase 91 octane at the gas station can it vary between 90 -91 or does it have to be minimum 91? I only use a little octane booster with each fill up when i purchase 91 octane just to be safe that I am 91+. If I can find 93 octane or better I don't bother adding any to the tank.

Depends on where you live. In Maryland, gas is randonly tested by the state and if found to be below advertized spec ... the fine is huge. Its just not worth doing. In states that have no testing ... yeah, sometimes its going to be below the advertized number ... and can be more than a number or two ... sometimes 5. Some brands value their reputation and never sell below spec anywhere, others don't give a crap and will sell you crap.

Are you using locally purchased plastic bottle octane booster?

[Dave Strong]

Depends on where you live. In Maryland, gas is randonly tested by the state and if found to be below advertized spec ... the fine is huge. Its just not worth doing. In states that have no testing ... yeah, sometimes its going to be below the advertized number ... and can be more than a number or two ... sometimes 5. Some brands value their reputation and never sell below spec anywhere, others don't give a crap and will sell you crap.

Are you using locally purchased plastic bottle octane booster?

Happens up here as well.

Dave

[MattGreen]

what is the +/- percentage factor with the retail gas octane? When you purchase 91 octane at the gas station can it vary between 90 -91 or does it have to be minimum 91? I only use a little octane booster with each fill up when i purchase 91 octane just to be safe that I am 91+. If I can find 93 octane or better I don't bother adding any to the tank.

If I remember correctly motor gasoline blends are done to +/- 0.1 AKI. Any less than the spec is basically a contractual and/or regulatory violation - QA/QC is a big deal in the refinery world. Any more is called "octane giveaway" and severely hurts bottom line since the high-octane blending components (i.e. reformate, alkylate) are much more expensive to make then lower-grade blend stocks.

Matt

[FMP]

So once we've got over the pre ign / detonation can we add propylene oxide for more BTU's ? I've heard 8% increase in HP with 12:1. Handle with care !

[Markus]

If I remember correctly motor gasoline blends are done to +/- 0.1 AKI. Any less than the spec is basically a contractual and/or regulatory violation - QA/QC is a big deal in the refinery world. Any more is called "octane giveaway" and severely hurts bottom line since the high-octane blending components (i.e. reformate, alkylate) are much more expensive to make then lower-grade blend stocks.

Matt

Over here, most refiners are a bit more generous than that: typical RON 98 is actually 98.5 (except Shell that sells a crappy mix with more ethanol and only RON 98.2)

[Markus]

'
95 RON is iqualent to 91 US octane so I don't know why Mercury saying 96 RON.

95 RON in this part of the world is 90 (R+M)/2. You would need 96 RON to get 91 (R+M)/2.

That is why Mercury says minimum 96 RON.

[Mark75H]

So once we've got over the pre ign / detonation can we add propylene oxide for more BTU's ? I've heard 8% increase in HP with 12:1. Handle with care !

Prop adds oxygen (like nitrous), not BTU's BTU's come from fuel.

[Steelborn]

There's only 95 Ron avaliable, I'm not sure what to do, would adding small amount of Aces booster solve a problem? It's literaly 1 octane or less difference...
Im really trying to do best I can to stay away from verados...

[Dave Strong]

Sounds like Mercury are just covering their butts, seems BS they are selling a consumer engine that can run on pump gas not available to most. Not all up on the new 300XS but sounds like smoke and mirrors. If you want the facts call Fullers Marine and talk to them as Merc HP dealer they should be able to set you straight. JMO

Dave

[FMP]

Prop adds oxygen (like nitrous), not BTU's BTU's come from fuel.

Adding O2 will promote more complete Rx ,thus more heat CO2 and H2O vapor to the extent that the limiting reactant is the fuel . Over simplified considering the all partial and by products but...

[dwilfong]

Prop will increase the burn rate of the fuel. BUT it will be gone in less than a day after you ad it.
Great for high CR eng running high octane fuel. But not for every day use. That and it is $80 Gal.
DO NOT GET ANY ON YOU!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
It will give you brain cancer !!!!!!!!!!!!!!!!!!!!!!!!!!!!
You can taste it in your mouth if it spills on you and will boil if it hits the ground on a hot day.

[Markus]

There's only 95 Ron avaliable, I'm not sure what to do, would adding small amount of Aces booster solve a problem? It's literaly 1 octane or less difference...

No. ACES does absolutely nothing for the octane rating of the fuel. The company that markets it has confirmed that the effect of ACES cannot be measured in a knock test engine. It does have some effect of the amount of money in your bank account, though.

You need to either blend with some high-octane racing fuel or with toluene. There is no free lunch, unfortunately.

[Markus]

On what motors you using toluene?
Are you doing it because of no 91 or higher avaliable?
if something happens to new motors under warranty and Mercury finds out that I was running 87 I can kiss warranty good by...
I'm not rich enough to gamble with $40k.

How would Mercury be able to tell whether the toluene was mixed in by you or by the refiner?

Toluene is a major component of 98 RON gasoline, particularly summer blends.

[Markus]

Cast your gaze wider it only takes a few grams per gallon say .5 percent by weight tetraethyllead to boost the octane of most pump fuels 12 full points. TEL doesn't even have an octane rating hy itself as it is not a combustible hydrocarbon. I suspect there are metallic anti-wear additives in some of the oils that are highly effective octane reducers.

There is some strange speculation going on here.

It is not like they chose to poison half of humanity with lead because there were thousands of compounds to choose from and they just picked tetraethyl lead because they felt like it. The effect of lead on anti-knock properties is unique. If it had been possible to use something equally cheap to boost octane instead of using more expensive hydrocarbons, the refining industry would have headed that way. Instead, it had to invest billions in equipment for producing hydrocarbons with higher octane ratings to be able to supply unleaded high octane gasoline.

[Steelborn]

Some one says yes Aces, some says no...
Toluene it's not problem to get, just to calculate how much you really need...

No. ACES does absolutely nothing for the octane rating of the fuel. The company that markets it has confirmed that the effect of ACES cannot be measured in a knock test engine. It does have some effect of the amount of money in your bank account, though.

You need to either blend with some high-octane racing fuel or with toluene. There is no free lunch, unfortunately.