104+ Octane Booster

Trackaholic said:

I'm in CA where our best widely available is 91. No problem with the GT350.

I'd run 93 if we had it but since we don't I just use 91.

You will lose a little fuel economy with oxygenated fuel, as the 10% ethanol has less energy than the 10% gasoline it replaces. If you normally run 100% gas, that might explain the MPG drop. Or it could just be statistical variation.

-T

Click to expand...

Up til now I have only used the 10% ethanol blend.

The station that has no ethanol fuel carries 90 octane.

I been thinking about doing a dyno run without and with octane booster just to really find out if it works. I always run 91 octane and pretty much have to with the PP2 installed.

I'll report my findings when I do it.

I wouldn't use octane booster. Most octane boosters do very little to actually make your octane higher (and could actually cause issues down the road). Maybe by 1 point depending on how many gallons it's mixed into.

Stick with normal 91 fuel. You'll be fine.

Either that or move to Texas.

Luckily we have Husky 94 octane E10 tier 1 in our neck of the woods.. straight gas would be Shell Vpower 91 octane. So far zero probs with the Husky.

.

melwff said:

for what it's worth this link rates 104 at 9 points. A point is 1/10 of a pump octane number so adding it to 87 octane will barely make it to 88.

https://scanneranswers.com/best-octane-booster-and-fuel-additives/

Click to expand...

You could get the same octane by using e15(88). Lower price on the e15 as well. Some stations use it and our cars can take e15 stock.

Trackaholic said:

I'm in CA where our best widely available is 91. No problem with the GT350.

I'd run 93 if we had it but since we don't I just use 91.

You will lose a little fuel economy with oxygenated fuel, as the 10% ethanol has less energy than the 10% gasoline it replaces. If you normally run 100% gas, that might explain the MPG drop. Or it could just be statistical variation.

-T

Click to expand...

I'm going to stop you right there, its ok with decent 91, but I got some stale 91 in a station in CA and the GT350 was downright allergic to it. I mean worse than the time the dealer put 87 in my STi. And if you've run it on good 93... you'll be disapointed in good 91.

That said the GT runs less compression and shouldn't have the same craving for super high octane than the 5.2L.