I only use Shell V-Power, or Exxon Premium. 93 Octane only.

 

Wrong... it doesn't change the mixture, it pulls timing in response to the detonation the knock sensor WILL hear with low octane gas... and that reduces gas mileage, power, and increases the exhaust gas temp... plus detonation KILLS the piston tops and valves... given enough of it...

Point being... don't do it... terrible idea...

 

I used to test gasolines for octane ratings at a company awhile ago (actually a long time ago), so bare with me.. Also, I hope this hasn't been covered by another thread since I haven't searched.

To test for an octane, I would run two tests and average the number to get the numbers you see at the pump ( 87, 89, and 91).

*it gets fuzzy here*

One test would basically be simulating a car driving on a flat plane with no resistance at a cruising speed of roughly 40mph (forgot the exact mph, but wasn't super duper fast). We would simulate this by having an engine with an adjustable head so we could cause knocking. When it would knock, we would record the readings. Usually you'd get a 100+ octane rating since there was no resistance and your car isn't struggling.

The other test was to simulate a car going up a hill of 30 degrees incline at 60 mph (again, not completely sure, but the set up of having resistance is right). The test would yield a lower octane rating of 70's to 80's.

Take the 2 numbers average them and you have your pump octane number (87, 89, 91). If you look at some of the pumps you'll actually see RON + MON avg on the stickers.

So point being, if you live in a relatively flat city, I don't see the need to run super high octane gas. I personally use mid grade gasoline and put supreme gas in after oil changes. I tend to stick to big name gas companies too. Some 2nd tier gases just meet bare minimum with some of the testing I've done and seen. If your wallet is hurt, don't worry to much.

 

wait, what part of brooklyn were YOU in? i havent seen any prices around here in the 4 dollar range for the past 2 years

and last month it hadn't gone ANY where past the $3.25 mark even at the most expensive sunoco

 

You're lucky you have 93 octane, we have 91

 

87 octane here. 5+ years, 120k miles, and still going strong. I haven't had any issues at all. Except for probably the poor gas mileage I get(~18-19mpg). But that's acceptable to me.

 

91 FTW or higher..

 

Don't do it..................

 

I always put premium gas in....always... i don't understand why not its not that much more expensive...If you drive a Lexus (or any foreign car for that matter) you should be prepared to pay more for everything. If not, you shouldn't have bought one!

 

just sick that big mac and send the extra couple of dollers

 

I pay 30 cents over regular for premium, which is ~10%. When I use regular, I can sometimes lose ~10% in fuel economy. So it's a moot point, for me at least, shell out for the good stuff.

 

Premium!!!!!and stop ruining the <<<<1UZ-FE>>> :C

 

there couldnt be anyone more informative than you here probably. Hah, a guy who tested octanes, thats interesting stuff.

fwiw, in my little experience, fuel quality really comes into play when you're running high perf engines, high compression, high boost etc. I havent noticed too much a difference on any of my tame compression, NA (wife's ) cars. The GS300 seems to respond about the same to 87.

Interestingly, East coast 89, 91 and 93 were different than west coast 91. WEst Coast 91 is more similar to east coast 87-89 than anything near 91 in the east.

I derived all this from hours of logging my audi S4 in the east, and later in the west.

I have noticed a slight lethargy when using 87 instead of 91, the timing retardation would explain that.

good info here.

 

I DONT use Regular, just like I dont use Aviation Fuel to make it go faster. Why not Kerosene? Water would be cheaper. And not that expensive bottled water but the free stuff out of your tap. Get my point? USE WHAT YOUR OWNERS MANUAL SAYS. If you a burning a hole in your pocket, better to siphon gas out of your neighbors car to help your pocket book, but be careful. Someone was siphoning gas around here, so I decided to booby trap my car...poured a bag of sugar into my gas tank...decided to do my neighbors a favor and poured a bag of sugar into their cars too. Guy who siphons our gas is gonna get a BIG Surprise now. Hahaha.

 

I only use 93 in my 430.. but when i had my GS4 which was my DD i would switch it up occasionally. I do 90pct highway driving so it smooth cruising at about 80mph haha Reg. Mid or High test was all the same with my mileage i averaged 19.75mpg pretty much the whole life of the car that i owned it from 90-140k.. Just to be safe tho i would just stick with the 93 and geta DD that takes Regular..haha