2* degree and fuel

**chieflikalotapus** · 03-27-2008, 12:46 PM

just curious if you can use regular 87-88 octane or do you need to use 91-93. will it make a difference

baseballfanz · 03-27-2008, 01:00 PM

Just use regular fuel. It's not a big enough advance to required higher octane

sudden urge · 03-27-2008, 01:01 PM

88 would be ideal for the two degree advance, but 87 is ok. I usually fill up 14 gallons of 89, then fill with 87 the next time. That keeps it at 88 most of the time.

Zdr93523 · 03-27-2008, 02:01 PM

Your octane rating will also completely depend on the elevation where you live. In Utah we get 85, 87, and 91, sometimes 89. The higher you are

the lower the required octane. This is due to air density. There is quite a big performance difference between sea level and high elevation.

albonismo · 03-27-2008, 02:44 PM

yea we get 89 91 and 93 here in houston. 87 is unheard of.

q about the advance. do you lose gas mileage by doing this? not counting punching the pedal more

**Schrute** · 03-27-2008, 02:57 PM

Quote:

Originally Posted by Zdr93523

Your octane rating will also completely depend on the elevation where you live. In Utah we get 85, 87, and 91, sometimes 89. The higher you are

the lower the required octane. This is due to air density. There is quite a big performance difference between sea level and high elevation.

Am I OK to run 85 with the advance then? I've been running 87 (mid-grade here in Utah) since I got the advance, but wouldn't mind dropping back to 85 if there are no ill effects.

Any input appreciated.

sudden urge · 03-27-2008, 06:59 PM

Quote:

Originally Posted by Schrute

Am I OK to run 85 with the advance then? I've been running 87 (mid-grade here in Utah) since I got the advance, but wouldn't mind dropping back to 85 if there are no ill effects.

Any input appreciated.

You're ok with 85 and the elevation there. Also, the colder air temps of winter weather lower the octane requirement. In summer, just change off every other tank to 87 octane.

Zdr93523 · 03-27-2008, 07:21 PM

I'm in Utah too, just run 85 year round, you'll be fine. The every other tank thing makes no sense... octane rating prevents knock per air density... Utah is high elevation/thin air therefore it has a low octane requirement.

bigfatboss · 03-27-2008, 07:54 PM

Hey I am in Utah also. Where did you guys get the 2 degree advance done? Can I do it? How does it effect fuel efficiency?

**Schrute** · 03-27-2008, 08:05 PM

Thanks for the replies!

Quote:

Originally Posted by bigfatboss

Hey I am in Utah also. Where did you guys get the 2 degree advance done? Can I do it? How does it effect fuel efficiency?

There's another thread where we discussed where to get the advance, click here.

My mileage has gone up a little (about .5 MPG) since the advance, but that could also just be from the weather warming up.

sudden urge · 03-27-2008, 08:05 PM

Quote:

Originally Posted by Zdr93523

I'm in Utah too, just run 85 year round, you'll be fine. The every other tank thing makes no sense... octane rating prevents knock per air density... Utah is high elevation/thin air therefore it has a low octane requirement.

Colder air is more dense than hotter air (summer vs winter), every other tank means 14-18 gallon mix unless you run it down to empty each time.

TitanLou · 03-27-2008, 08:43 PM

I've been holding off because I was worried about this stupid 86 octane here in NM. After reading this I think I'll go ahead and get it done.

firulice · 03-28-2008, 11:01 PM

Quote:

Originally Posted by Zdr93523

I'm in Utah too, just run 85 year round, you'll be fine. The every other tank thing makes no sense... octane rating prevents knock per air density... Utah is high elevation/thin air therefore it has a low octane requirement.

You other guys in Utah should come out off-roading with us next weekend?

**Schrute** · 03-29-2008, 12:25 AM

I'm there!