Next week, I'm driving from Virginia to California (about 3,000 miles total). Virtually the entire trip will be on the interstate, part-throttle, steady-speed, below 3500 RPM.

Since 87- or 89-octane gas is cheaper than premium, and has higher energy content as well, would it make sense to use the lower-grade gas for the long highway drone out west?

Other than a cold-air intake and exhaust, the drivetrain on my car is stock.

 

Good thought. I think lower octane gas will retard your timing and result in lower gas mileage. Now is a good chance to find out . . . and you're not talking real big bucks so why don't you experiment with 750 mile legs and let us know the result.

Say, what route are you taking anyway?

 

What part of California will you be in?

 

Well, using lower octane gas will retard the timing, but *only* if the engine's knock sensor detects detonation in the engine. Since detonation is usually more of a problem in full-throttle or high-rpm situations, it's likely that part-throttle, steady speed driving on the highway won't cause pinging, even with lower-octane gas. The specific energy content is higher for low-octane gas, so as long as there's no pinging that causes the engine to pull timing, I would actually expect the fuel economy to be a little bit better with 87- or 89- octane.

I'll be taking the "northern route" from Virginia to Dallas (Virginia, Tennessee, Arkansas and into Texas). I drove the same route from Virginia to Dallas and back last month and averaged about 31.5 MPG using premium gas (91 or 93 octane, depending on what was available).

From Dallas to Monterey, I think the route is mostly I-287 and I-40 all the way. I've never driven that route before, so I don't have any expectations as to average fuel economy for that part of the trip.

 

Monterey - near Pebble Beach, about 350 miles north of LA. I'll be going to the Naval Postgraduate School for two years, getting a Master's degree. My wife is finishing up her own Master's here in Virginia, and then needs to teach in Virginia for two years to fully-accredit her license, so we'll be on opposite coasts for the next two years.

It's funny, but at 37, I feel like a college freshman, loading up my MINI with the stuff I'll need and driving across country for school. I'm even packing the obligatory guitar!

 

Gee, you'll be perfectly positioned to take the "Extraterrestrial Highway." Does that scare you, how about the "Lonliest Highway in America." It is a MINI afterall. About half the traffic on I-40 "isn't your kind" (tractor trailers).

 

Honestly, I am a little bit bummed that the "loneliest phone booth" is no longer in the Mojave.

I already have some experience with the "loneliest highway in America" (Nevada's Highway 50, for those that haven't been there). I've been out to Naval Air Station Fallon, NV several times for airwing exercises, so I've taken cars and motorcycles out on Hwy 50.

I'm not going to be doing much sightseeing on the trip out there, though. I still have to check out of my current assignment here in Virginia, leave on Monday the 25th, and report for duty in Monterey by Monday, July 2nd. With a one-day stopover in Texas to see my parents, I expect to get into Monterey on Friday the 29th and start looking for an apartment on Saturday. Short-fused orders really suck - I didn't even know I was going to Monterey until Monday of last week. My official orders haven't even been posted yet.

 

Welcome to the area, Scott!

I did the same trip in 2005 (bought my MCS in VA.) I burned about 100 gal of gas, so the potential savings is ~$20. Not a big deal either way, but like BlueBonnet mentioned, it might be interesting to try a tank or two one way, then the other. The way I look at it, you never know when you're going to need the power, and I'd rather forego a bottle of wine than NOT have that power when I needed it. No sense going above 91 octane (that's all we get out here), but I'd use that.
I averaged 30.2mpg with high of 33.6 and a low of 28.9mpg.

Drop me a line if you'd like to meet up with a friendly local.

 

Once I get to California, I'll definitely use premium exclusively. I'm just curious about trying the lower-octane gas for the trip out there, more out of curiousity about the difference in fuel economy than the monetary savings. As you say, we're only talking about $20-30 difference over the duration of the 3,000-mile trip.

I'll be sure to PM you once I get settled in. I'm hoping there's an active MINI community (and autocross opportunities) near Monterey.

 

I just recently drove from KC to Yosemite and back...right at 4000 miles. I used 91 the entire way (including a tank at $4.09/gallon INSIDE the park).

I averaged right at 36MPG the entire way and had smooth sailing no matter the *cough* speed.

If you didn't have a destination in Texas I'd highly recommend the I-70 to I-15 route...if nothing else for the twisties and scenery.

 

I used to do this test with a Volvo I had-I always got better mileage with premium that out weighted the cost difference.

It will be tough being apart from your wife for 2yrs but you will be in one beautiful area. I travel a lot of business and northern Cali is my favorite place. I'm sure Eric can give you the true gen on the MINI scene but I can say from being there that the bay area is very high in MINI's and the roads are great around there! You also mentioned a guitar- be sure to give Santa Cruz Guitar Co a visit and for a great guitar store check out Gryphon Guitars in Palo Alto- heck just check out Palo Alto-great town!

 

I agree.....stay with the premium. I can get over 36 mpg on highway driving easy.

 

Actually, for my MCS, less than $20 would be more correct using the formula: 3000 miles, divided by 33 mpg, times the extra 20 cents for premium, equals an additional $18.18 for gas.

 

Is that according to OBC or calculated? I feel like such a gas hog.
I'd echo the I70-I15, but alas - family.


Scott - they used to run autox in Marina (very close). I'll check to see if they still do. I've run a few, but got frustrated with 3 minutes of seat time for a day's effort. Laguna Seca is close though.

 

Oh dear god, just wait until you discover Hwy-1 with your Mini.

Most autocrossing out here is SCCA San Francisco region: http://www.sfrscca.org/ Be prepared to do a little driving to get to events.

You will be right next door to Laguna Seca, and looks like in time for the 2007 Monterey Historics. A must see event.

I recommend taking whatever route gets you on I-80 West to CA. A lot easier to get to Monterey from that direction.

 

For the first 5K miles on my MCS, I used mid grade all the time without issues. No noticable lose of power or drop in fuel economy. If fact, the car started better in the cold mornings because the fuel was easier to ignite. As long as the car isn't pulling timing, it's money in the bank.

In case you are wondering why I stopped doing that after 5K miles was because I started modding. With a new pully, I effectively bumped up compression, so I switched to premium full time.

 

Hey, I just want to say have a nice trip and hope you do well at school. Sorry to hear about your situation (wife staying) but I am sure it will be for the better. By the way, do you have children? I am only asking this because if you do, that makes it even harder. Anyway, good luck and send pictures of your trip with your MINI!!

 

I do believe we have a serious, serious issue with priorities here.

Too bad Professor Dave isn't ginning up the answers anymore.

Since drinking and driving don't mix, I believe it is proper to go ahead and buy the good gas then, in a parallel universe, go ahead and buy the good wine.

You can probably save on baby clothes, presents for the wife, something . . . .

 

Hey, good driving and have a safe trip. Taken that 287 route many times. Not the most scenic (ok, down right ugly) and it's mostly Semi traffic but it's pretty smooth sailing at least. Be sure to gas up in Decautur because there's slim pickings past there until you get up near Amarillo.

 

If you love your MINI...stick with the premium petrol!

 

I actually get a rough or noisy idle when I run lower grade fuel. It just sounds a little less tight. Is that the ping/knock result referred to earlier? Does it hurt her (mechanically) short term?
Please define "Pulling Timing"

06 justa 21k - by the way.

 

'pulling timing' - the ECU retards the timing (fires the spark plug later) to reduce the risk of detonation.
That generally happens under load vs. at idle, but if a particular fuel makes the car sound funny, don't use it.

 

Good Lowd!!
For a STUPID test my last half tank was low/cheap stuff. GRRR
I just refueled with top shelf and added the Techron.
WEEEEEEEE
Its a "JUSTA ROCKET" - LOL!! Well the new short ram intake helped too!

 

Hey, I will join in the fun too!!