94 octane gasoline = quieter ICE

I always find it amazing how little some people drive... LOL. Why even have a car.. just Uber everywhere if your using it that infrequently.

I put 1000 mostly city miles a week on my 2008..when I'm working.
Have 234,000 on the car.. I'm
Just finished a 5200 mile road trip.

Get out and drive it...
Just my $.02

Posted via the PriusChat mobile app.

 

When you're drinking that little coffee, I guess you get to know the flavor of each bean a little better.

Congrats on the fuel cutback, looks like normal findings- there would be less knock with a higher octane fuel, and modern cars are programmed to almost-knock all the time.

 

Ok, slick. Ease off the throttle a bit! It's mostly older folks that don't drive as much. We put in our time, and now we try to enjoy a nice relaxing retirement. But we still like to have a good reliable vehicle on hand. Uber sucks! I only drive about 7,000 to 10,000 miles per year. The freeways are crazy, the big cities are crazy, traffic is crazy, and the speeders are insane! I'm considering a move to Mars.

Back on topic. I think using 94 octane is unnecessary, won't improve performance or quiet the engine, and is a waste of money. But you Prime guys hardly use the ICE much, so I guess it doesn't matter.

 

Oh, and for the OP, don't take comments here personally. Keep posting your findings. We just like "ribbing" you (and each other).

 

My theory is that the high test fuel has fewer marbles in it, hence the quieter engine.

Seriously, though, I can't see that 94 octane hurts anything but the cash flow, so go for it if you want to. I waste my money changing the oil in my PiP every 7,500 miles or so when half my miles are EV. It's better than topping off your AGM battery with water, right?

 

Don't think 94 should be quieter unless the orig fuel was so bad it was knocking. Even if there is residual water in the E10, it would be dissolved water so I would not expect a change.

 

My car is specced for 91 octane and that's what I use and I also use Top Tier gas. For the few extra pennies and the infrequency that I buy gas, why skimp.
Just go with what your car uses and stick with a Top Tier gas.

 

I washed mine last night and it is much quieter. When I wax it, I need a stethoscope to hear the engine —LOL

 

Add a couple gallons of 94 octane, turn the lights off and put on some mirrored sunglasses and you may qualify as a stealth vehicle.

 

Without measurements from a meter, this almost certainly a classic case of the placebo effect.

 

I tend to agree that's it's a placebo effect. Same thing happened when I switched over to Mobil 1 oil. I thought my noisy engine was quieter for a day or two, but then the ol' growl came right back.

I will be the sucker. This theory needs to be tested in a regular gas-guzzling Prius. You Prime guys rarely use your engine. Next time I fill up, I will pour in the hot 94 stuff and report back to you. Premium is currently only $4 per gallon at Chevron (US).

 

I use a nitromethane/methanol mix. It also makes my 1/4 mile times much faster. You know, like the NHRA dragsters use.

 

It is HIGHLY unlikely that the octane rating of the gas you put in has anything to do with what you observed.
Your car absolutely, positively will NOT benefit in any way from higher octane.

The gas in your tank initially likely was 6 months old or more. Just getting fresh gas in there of ANY KIND probably would have had a similar affect.

AND.....there is only so much you can do to prevent the fuel from going "bad".
I think you should adjust your driving habits so that you use up most of what is in the tank at least every 6 months.
Even then, stabilizer is a good idea.

 

Mid-grade might indeed be a "mix" but finding any grade that is E0 is still pretty rare.

 

I'd agree with that... data from a knock counter or maybe something showing the spark advance averages for each fuel source would probably do it.

 

ScangaugeII can report ignition timing.

 

Love my Scangauge 2. I have two of them. Only one is updated to be able to report the tire pressures. That is why I bought it. However, the second one intermittently does not turn off. It has not been upgraded to the latest version. I also forgot to plug in the car. The older Scangauge has been left on in the past when it was plugged in and I never had an issue. I found out the hard way, Yes, it will run down your 12V battery and no you can not drive it with a dead 12V battery.

 

I got bored this morning. So I filled up (3/4 of a tank) with the highest octane grade at Chevron... It's 91 octane, here in California. I also washed and vacuumed the car.

I can't believe the engine now. Total silence! Even the road noise disappeared! And my MPG jumped up to 199!

( I also have a cool mountain cabin I will sell you, in Death Valley, California. Cheap! )

 

I bet it’s right next to the ocean front property.

 

I am still waiting for my 2018 Prime Technology (Premium) in Blue Magnetism to arrive. Currently drive a corolla and use 91 V-Power from Shell, and can tell you the car idles smoother, and responds better in the summer heat with it. The reason I use it is two fold. The better fuel additive package with upper cylinder lubricant keeps injectors and rings cleaner, and in the case of the prime will keep the EGR clean. The higher octane improves my mileage a tad because it has zero ethano, and this also leads to better low load idle qualitl. Only brand in Canada I know of that has a zero ethanol content.
Am I blowing a bit more $ than I need? Yup, but he long term benefits outweigh this. On my last 2000mile trip my Corolla averaged only 5.2L/100
or about 45 US MPG.