Gumout Octane Booster, 10 oz Bottle (Pack of 6)

Our two oldest cars, 58 & 54 years old, are still smoking the competition due in no small part to the effectiveness of this stuff.

This is the best stuff I have found to make a noticeable difference in the way your car runs. I have used in everything from a turbocharged MB E550, to a Firebird Trans Am, to a Subaru and a Nissan. You will instantly hear your engine running smoother, and at a far better price than other products made by STP for instance. I drive V8's because I have always regretted when I didn't at some point, and this counteracts bad gas mileage whether you are burning regular, or the premium grades. What that means for me is when I drive the speed limit, or near it, I'm making up to 6 mpg better than when I don't use this. Even if I drive more aggressively I get about 2 mpg more. I used to make a separate trip to Walmart just to get this product, but now get it at my front door thanks to Amazon stocking it. It's cheaper to buy them six at a time this way anyway.

What I liked about Gumout octane boost is that we did notice a real gain in mpg in our vehicles,a 2009 Subaru Forester and a 2002 Honda Crv which are both daily drivers.Noticeably more power and smoother acceleration noticed in both vehicles which both have over 110000 miles.I think this additive is a good alternative to higher octane fuel. Try it and you will see!!

Nothing

Works great

This added octane booster, along with premium gas, smooth’s out both my Deluxe and Tri-Glide Harleys, and stops all backfiring and popping. Priced well.

This product truly enhances octane levels. I have to at times settle for 87 octane for a motor that requires 89 octane. This additive gives it what it needs!

I have a very small business cutting grass. This product works very well.