View Full Version : Mid-Grade Gasoline?

06-11-2009, 02:22 PM
Ok excuse my ignorance on this, but what is the point of mid-grade (89) gasoline. From what I gather, Regular gas should be enough for a normal car to operate while Premium gas is for the more performance oriented cars. What type of cars require Mid-grade gas or is it just another way for the companies to make more money?

06-11-2009, 02:23 PM
Nothing really. Midgrade = blend of the two gasoline at the station. Its for those people that want something "better" but not fork out the extra penny/L.

06-11-2009, 02:25 PM
mid grade is for those who cant afford to buy high grade and feel to bad putting in regular...

Jason Lange
06-11-2009, 02:25 PM
Ya I can't see too many people actually buying mid grade.

As for your sig,

Sperms have a living of 3 days before they die in a man. Ladies do you really want to be a killer? Well DO YOU???

I see what you're trying to get across but sperm die in like 30 seconds after you ejaculate and even quicker in a chicks stomach so it really makes no sense.

06-11-2009, 02:25 PM
My boss says his 300C states in the owners manual it requires 89 octane.

06-11-2009, 09:20 PM
Mid grade is all you need for stock high performance N/A cars at this elevation.

06-11-2009, 10:35 PM
Originally posted by buh_buh
Mid grade is all you need for stock high performance N/A cars at this elevation.
Yes, but aren't the octance ratings here adjusted for altitude??

In the Rocky Mountain (high altitude) states, 85 AKI is the minimum octane, and 91 AKI is the maximum octane available in fuel. The reason for this is that in higher-altitude areas, a typical combustion engine draws in less air per cycle due to the reduced density of the atmosphere. This directly translates to reduced absolute compression in the cylinder, therefore deterring knock. It is safe to fill up a car with a carburetor that normally takes 87 AKI fuel at sea level with 85 AKI fuel in the mountains, but at sea level the fuel may cause damage to the engine. A disadvantage to this strategy is that most turbocharged vehicles are unable to produce full power, even when using the "premium" 91 AKI fuel. In some east coast states, up to 94 AKI is available [1]. In parts of the Midwest (primarily Minnesota, Iowa, Illinois and Missouri) ethanol based E-85 fuel with 105 AKI is available [2]. Often, filling stations near US racing tracks will offer higher octane levels such as 100 AKI.


06-11-2009, 10:39 PM
i use mid grade for my car. it says to run premium but i never have. :dunno: