[03trdblack]

Why would we need gasoline that doesn't pollute as much (or provide as much gas mileage) in the colder winter months vs. the summer months? What makes the winter so special that we have to suffer with lower performance all winter just to have better emissions for a few months. Wouldn't it make sense to have lower emission gasoline all year 'round if they are that worried about the pollution?

On a side note, will increasing my octane (going to 89 instead of 87) bring back my lost mileage/performance until they bring back "summer" gas?

 

[elgecko]

Why would we need gasoline that doesn't pollute as much (or provide as much gas mileage) in the colder winter months vs. the summer months? What makes the winter so special that we have to suffer with lower performance all winter just to have better emissions for a few months. Wouldn't it make sense to have lower emission gasoline all year 'round if they are that worried about the pollution?

On a side note, will increasing my octane (going to 89 instead of 87) bring back my lost mileage/performance until they bring back "summer" gas?

Temperature inversions, which are common during the colder months, tend to trap vehicle emissions (namely carbon monoxide) close to the surface, not good. Adding oxygenates to gasoline allows it to burner cleaner and thereby reduces carbon monoxide emissions. During warmer periods, carbon monoxide can easily disperse into the atmosphere.


You can check if your area is subject to the Winter Oxyfuel Program here:

http://www.epa.gov/otaq/regs/fuels/oxy-area.pdf

 

[Breathegood]

Yeah, what elgecko said, and as for your second question. I get no noticable gains by upping the octane in the winter time. I just try to run a fuel system cleaner with the first fillup of every month (I put a lot of miles on the truck). This spring, when that oxygenated crap is gone for a few months, I'll do a full on Seafoam treatment to clear out the garbage. Personally, I think the switch to oxygenated fuels is a bunch of crap. I would like to see conclusive results that show the reduced emissions from oxygenated fuels are actually greater than the extra emissions from burning more fuel.

 

[elgecko]

Here's a good study:

http://www.epa.gov/otaq/regs/fuels/ostp-1.pdf

 

[Breathegood]

Thanks for the link. Looks like a good toilet read!

 

[03trdblack]

Ha, that link references a study made in my hometown of Raleigh, NC.

 

[CMB1998]

Ha, that link references a study made in my hometown of Raleigh, NC.

What tires are you running?

Chris

 

[03trdblack]

Cooper S/T in a 265/75/16 size. You can see better pictures on my link.

 

[BuckeyeTaco]

Another reason for the "winter fuel" is the decreased evaporation or oxygenation rate that occurs at colder temperatures. The winter blend atomizes better in colder temperatures, thus allowing the engine to start quicker. The downside of this is if we get a nice warm spell in the middle of winter, we experience a lot of "vapor lock" if people don't allow their engine to completely cool before restart. Most of this can be taken care of with a change in the ECU program, but most manufacturers don't do it unless they experience market problems.

 

[03trdblack]

I just don't really understand why here in NC we have that gas. It doesn't really get THAT could here in the winter. In fact it was 75 here yesterday. I guess I'll just have to suffer until spring.