I bought a bottle to try it out. How much will it boost a certain grade of gas? Say I was to fill up with 89 or 93 then throw in the octane booster. Also, no 91 around here so would this be enough to add to a tank of 89 for a 91 tune?

 

The STP octane boost is pretty much worthless as are most of them. The most boost I've ever seen in testing was 1 and most were 0. I wouldn't put it in my tank, it may cause more problems with fouling spark plugs, injectors and valves than it's worth.

 

Snake oil.[:@]

 

I think the owner's manual may specifically state NOT to use products like this in our vehicle because it can potentially screw with a lot of things in the car.

 

+1 waste of time and money. There are only a couple that actually work and they do not sell those at gas stations...

 

Ah, well damn. I guess ill drink it with dinner. Thanks.

 

ahh ahhaha good one chase it with some matches.

 

I love the brands that claim "Add 5 to 7 points to your octane rating." The fuzzy math they use on the bottle is hilarious - if you look closely, it's "0.5 to 0.7 points." So, your 87 octane goes to 87.5 or 87.7.