Gas Prices

we use premium for our little mazda miata because the manutfactor said it was required.. otherwise i would be buying the "cheap" :P gas at $2.05 (california).. but really the pricing works out.. i may have to pay more per gallon.. but that little miata barely uses any gas - compared to my truck!

Teresa

[RockyMtnRay]

Bill wrote:

Veering a little off topic - CWB mentioned the price of 87 octane, and it reminded me of a question I've had for a long time. Does anyone actually use any gas other than 87 octane these days?

I do...sorta. Here in Colorado Springs, the octane of "regular" is actually 85, mid grade is 87, and super premium is 91. This is because of the elevation (6500) with its lower atmospheric pressure, and associated lower combustion chamber pressures. However, I find my Jeep 4.0 will knock on dry days in normal driving with the 85 octane regular so I routinely use 87 (mid grade) (atmospheric water vapor is pre-ignition (knock) suppressant).

But when I'm going to tow the TM up the mountain grades going out of town on a hot, dry day, I've found that premium (91) is a necessity to prevent knocking until I get up to around 8500 feet. Apparently the sustained full throttle operation is getting something in the combustion chamber (carbon deposits, most likely) hot enough that I'm getting pre-ignition.

My Jeep is old enough that it apparently doesn't have a very sophisticated engine computer that automatically retards the spark when knocking occurs...which is just as well as that also cuts power.

Windbreaker asked how long I had used an ethanol blended gasoline: 13+ years! Multiple cars, some with 100,000+ miles, no problem. There used to be concern about problems with "gasohol", but all the major manufacturers now approve the ethanol blends. I've heard that methanol blends may have problems but since I've never had it available I've not done any research on it.

The only problem we had with ethanol was when we first moved to Iowa (from New Mexico - love those Texas jokes :-) ). Our car fouled the fuel filter a number of times until the ethanol cleaned the tank enough. This is common, from what I've heard. The ethanol dissolves enough junk that cars driven many miles (mine had about 60K on it at the time) clog the filters. There isn't any permanent damage, but it not a pleasant thing to be driving and then get a plugged fuel filter! We don't see any problem when we go on vacation (up to 5000 miles) when we don't use ethanol blends.

Pam S

Well, the results are in on what my friend told me. He said most don't mix anything in when they fill up, but a couple/few of them that do use special additives, such as Flying J's, DO add them while they're filling up their tanker trucks.........

[glow=red,2,300]Happytrails..........[/glow]

[Bill]

CC_turtles, and Ray -

A Google search for "Miata octane" turns up a number of items like http://www.geocities.com/masters_mia...iver07_01.html. A mild amount of support for Ray and his 14ers, but not for the Miata. My guess is that Teresa is not alone - I bet the dealers hype the idea that "this is a high-powered sports car - you can tell because it needs premium gas!" Sorry, Teresa, I don't mean to poke fun at your Miata, but dealers will do anything to sell a car, and the consumer pays the price. You might want to try a tank or two of 87, and see if there is a difference. Just a thought ...

Bill

So Pam, the problem is most likely the results of these folks just using one or two tank and not running it full time. I can understand that, slow as I am. Thanks.

Bill, i know the little miata is not a high powered sports car -- just a little economic sports car for fun ;D

the owners manual says to put the premium gas in... we bought the mazda from a volkswagen dealer.. it was great because he didn't know much about it.. we got a special edition at the regular miata price ;D

we could try putting in the 87.. but right now.. we are only having to put gas in it twice a month.. maybe if gas gets to $4/gallon.. we will give it a try

thanks for the info.. and for the link!!
teresa