MajBach
Chief Petty Officer
- Joined
- Jun 21, 2003
- Messages
- 564
Some of you might find this enlightening while others might consider it common sense. I myself was very surprised when I first learned about it since I had already arrived at a conclusion [erroneous] on the subject. <br />Decades ago when I got my first car, aside from waxing the paint right off of it, I always ran preium gas in it - and it was just a puddle jumping import. I read up on the pros and cons on running high octane gas in engines that didn't require it and then conducted all kinds of 'road tests' (remember I was 17). The first few times I didn't notice any better acceleration times or no increase in fuel economy, I assumed I did the tests wrong. I finally gave in after months - maybe years - and realized you can't make a '79 Accord go any faster or produce more power with additives or good gas. This conclusion was further substantiated when I tried running 130 octane av-gas in my car. (Our float plane bases cached huge tanks of fuel as one cannot get gas readily in the far north). In a vehicle that doesn't call for it, running higher octane gas is like taking vitamins when you already have a balanced diet.<br />So imagine my surprise when I notice a sustantial increase in performance and mileage when I ran high octane for the first time in my car after towing a heavy boat. I thought maybe the air was just dense or that recent car wash did more than clean the exterior. I later learned that high octane gas can greatly improve performance and mileage when used under heavy loads. In the 'old' days, this requirement was indicated by knocking when you put the hammer down or went up a hill. But my last car never did this so I never served hi-octane. Well, not to long ago I learned that most modern cars have anti-knock sensors ( I have heard of these before but never put 2 and 2 together). In other words, if your car starts to knock, the computer lowers the amount of gas it spits in to prevent the knocking or pinging. <br />When towing my boat, my vehicle went from 25 mpg to 29 mpg and there was one particular hill on the way to the dock that ALWAYS req'd me to shift down 2 gears; with the higher octane, only one. I measured this over several trips to be sure too.<br /> So all of you guys in my generation that have concluded that hi-octane gas does nothing for your car if the manual doesn't call for it, guess again. It actually might, give it a try.