The other day i went to Checker to buy some stuff to wash the truck. There were this little bottles that said they add up to 7 octane. There must have been atleast 4 different brands. Is this true? are the safe? anyone try them?

 

I'm sure it boosts the octane somewhat, but ive heard it wreaks havoic on your fuel system and plugs... but i could be wrong.

 

Those octane booster additives are a complete waste of money at best and at worst do actual damage. Several engine performance magazine have done articles on them and here's a quick synopsis: 1) If you read the can closely it says "up to 7 octane points". An octane point is .1 (1/tenth) of an octane rating number. 93 octane becomes "up to" 93.7 octane. 2) The active ingredient in those cans is usually a dry cleaning solvent like toulene. For their price you could buy gallons of it. 3) Those additives often turn your whole fuel system an orange/red tinge. No damage unless you're trying to read the color on a spark plug. 4) More octane only helps if the engine is predetonating, if not, it will do nothing to make a car any faster.

If you want more octane buy race gas (ie. 100,110,118 octane).

 

Thanx for the info AintNoHo.

 

go to a small airport and buy av gas

 

Sorry for the noobness, but whats av gas?

 

AintNoHo is correct. Octane boosters are a complete waste of money, especially if you don't hear detonation during acceleration. Av Gas is short for Aviation Gas. Avgas is a high octane fuel used in aircraft with piston engines. I think avgas was used in race cars (NASCAR) a couple years ago.

 

I know a guy that runs 93 octane most of the time but if he going to race and spray N20 he adds a few gallons of AV gas from the local airport to control detonation.

My question is, is AV gas unleaded? If not it would play hell with O2 sensors.

... and what octane is it?

I'm just curious.

 

Summary of Avgas:
http://www.osbornauto.com/racing/race2avgas.htm
Sounds like all Avgas grades contain some lead.

 

Avation gas is rated 100LL (low lead). The avgas is used in piston airplanes and still contains a small amount of lead for engines without hardened valve seats...like older muscle cars. Toluene, an aromatic circular hydrocarbon chain, is a regular component of pump gas and is available at hardware stores. Premium street gasoline carries roughly 5% toluene, which helps octane ratings. 100-octane race gas has almost 25% toluene. Remember that adding toluene to 87 rated fuel will have a higher yeild than adding it to 92 or 93, due to the negative effect the addiditive has on these higher octane fuels. Also simply adding toluene in mass amounts WILL damage emissions equipment.