TESTED: Royal Purple Max Boost Octane Booster
To be honest we were not big fans of octane boosters. In the past, we have not been able to get good quantifiable results with them over the years. Older boosters ate up the fuel system or left weird deposits on the plugs and chamber. Engines that usually need higher octane are generally expensive so we have always just used racing fuel in them, Pump gas with conservative tuning for street cars and race fuel for race cars.
Meanwhile, Royal Purple had been bugging us about testing some of their new Max Boost octane booster. They told us that it would give us 30 points in octane which equates to an increase of 3 octane numbers and it would burn clean. Not being too enthusiastic about octane booster in general we let it sit around for about a month.
Well we happened to be dyno testing a Scion FR-S the other day. We hate dynoing the FR-S on our native supper crappy 91 octane California piss fuel. With its 12.5:1 compression and very active ECU with tons of command authority, the FR-S is very hard to dyno accurately on 91 octane. The power can wildly swing making it very difficult to get good data to see if your just bolted on part really did make more power.
You usually have to dyno an FR-S while monitoring it so the intake air temp, oil temp, coolant temp, driveline temp and electrical load can be kept consistent. If everything is kept the same from run to run then maybe you might get some consistency. It is really frustrating testing simple bolt ons for the FR-S because the power variation can be within the expected gains of the part and if the part creates more cylinder pressure, the changes to the knock limit will cause the ECU to dial back timing which effectively cancels out any gains the part might have within days or even hours of installation.
We noticed that guys posting dyno results in other states with 93 octane fuel didn't seem to have as much problems as we had. So when we found ourselves with an FR-S full of 91 octane on the dyno and a can of Royal Purple Max Boost octane booster in our hands we knew what we had to do.
We are now pretty enthusiastic about Royal Purple Max Boost and will continue to evaluate it in different cars and report on our results. If you have a turbo or high compression street car, some Max Boost could be a good insurance policy when doing a track day to keep any chance of detonation at bay while running under demanding conditions, especially when you are stuck with 91 octane fuel.