Going to Fill up with 93 after work

"Yowen - not necessarily not spaghetti and meatballs" (yowen)
10/22/2013 at 09:36 • Filed to: None

Supposedly I'll gain 10 horsepower and there will be some increase in MPG as well. This is on my '10 SHO, I'm very curious if I'll see/feel a difference in either. I keep a fuelly log after every fill up, so we shall see 1-2 weeks from now what my mpg's are!

DISCUSSION (34)

Nibbles > Yowen - not necessarily not spaghetti and meatballs
10/22/2013 at 09:39

I'm sure the engines have gotten better over the years but I can attest that, in my SPG, there is a very noticeable difference between using regular and premium fuel. Like, 10 PSI vs 17.5 PSI difference.

Yowen - not necessarily not spaghetti and meatballs > Nibbles
10/22/2013 at 09:46

What's an SPG?
PSI's where?

I've read that the mpg difference is enough to justify the extra cost of premium, I'll believe it when i see it though, haha. I agree that these days, especially with turbo cars there are more gains to be had with higher octane.

Nibbles > Yowen - not necessarily not spaghetti and meatballs
10/22/2013 at 09:50

Sorry:

SPG: Saab 900 SPG (Aero in the UK), mine is an '87.

PSIs from the turbo. If I ran regular, I'd see 10 PSI boost max. On premium I could hit 17.5 regularly, 3rd - 5th gear.

Also, when I stayed out of boost (for the most part) I netted 34.8 MPG. Well over the EPA's 26 MPG estimate. YMMV, my car is 25 years old lol

andriukas > Yowen - not necessarily not spaghetti and meatballs
10/22/2013 at 09:51

When I used to keep track of my MPG's ('10 Genesis Coupe 2.0t), I believe I averaged around 3MPG more filling with 93.

Nuggolips > Nibbles
10/22/2013 at 09:53

I assume you're talking about a Saab. All my H-engine Saabs always had terrible problems with anything less than 91. I had an NA 2.1 900 and if you tried to run regular fuel it would sound like a diesel with all the detonation. Even my 9000 with the 2.3 was super picky about fuel. Audible detonation low in the powerband, especially on a hot day. One time I tried to put midgrade in (87 octane here in Denver) and the fuel pump shat the bed (ok, that was probably a coincidence).

Nibbles > Nuggolips
10/22/2013 at 09:55

Yup, Saab. Yup, H-engine (B202). Yup, Denver.

Though mine has never been picky like yours have been. I could run the SPG on regular fuel (as long as I traded out the APC for a standard T16 unit) without detonation; I just wasn't allowed any real boost.

dinobot666 > Yowen - not necessarily not spaghetti and meatballs
10/22/2013 at 09:57

They recent switched over to winter blend here in the flyover states and my fuel economy plummeted. Also, there's a new state mandate that everything has to have at least 10% ethanol in it, which is pure garbage.

Nibbles > andriukas
10/22/2013 at 10:05

Just for quick calculation, let's use random values.

Let's say on regular fuel at $3.239/gal, you get 25 MPG. That equals $0.13 (.12956) per mile. Running premium at$ 3.539/gal you get 28 MPG. That equals $0.13 (0.1263928571428571) per mile.

Using these (fairly) arbitrary measurements, it could be said that you're paying no more to put premium in your car versus regular. Therefore the performance increase is an added bonus. Everyone loves bonuses.

Yowen - not necessarily not spaghetti and meatballs > Nibbles
10/22/2013 at 10:13

Wow that is a big difference in turbo pressure. Mine is electronically controlled, so I am sure it'll hit the same numbers as before. But I don't have a boost gauge (yet), so I'm not sure.

Yowen - not necessarily not spaghetti and meatballs > andriukas
10/22/2013 at 10:14

Wow that's a significant difference, I'm excited to see what my car does!

Yowen - not necessarily not spaghetti and meatballs > Nibbles
10/22/2013 at 10:14

hopefully my real-world numbers reflect this, haha. I'll have to make a note of the price of regular at the time of my premium purchase.

Yowen - not necessarily not spaghetti and meatballs > dinobot666
10/22/2013 at 10:16

I'm sure we'll be on it soon enough, if we aren't already. How would I know besides a possible drop in mpg...

dinobot666 > Yowen - not necessarily not spaghetti and meatballs
10/22/2013 at 10:20

October is usually when blends start to change. I might have to start putting premium in my Tacoma, just to avoid the wretchedness that is ethanol. I HATE it.

Nibbles > Yowen - not necessarily not spaghetti and meatballs
10/22/2013 at 10:22

You'd be surprised. Mine is electronically controlled (APC system - first in the world, Craig) and it definitely treats different fuel grades differently. Of course technologies have obviously changed in the last 25 years. I'd say you're almost guaranteed to see a difference, as higher octane allows for higher compression (which means more boost) without detonation. Not to mention these newfangled cars come with different mappings for what fuel type is sensed.

Honestly if you're a data hog like I am a calibrated pressure gauge would be a worthwhile investment. I've found that, even in newer performance cars, the factory boost gauge never really gives you a proper idea of where you're at.

MontegoMan562 is a Capri RS Owner > Yowen - not necessarily not spaghetti and meatballs
10/22/2013 at 10:27

There should be a sticker on the gas pump that says something along the lines of "blended fuel used between october- march" or something of the sort. It might say oxygenated but I don't remember the exact wording.

Yowen - not necessarily not spaghetti and meatballs > dinobot666
10/22/2013 at 10:30

hmm, premium = no ethanol?

Yowen - not necessarily not spaghetti and meatballs > Nibbles
10/22/2013 at 10:31

I was planning on getting an OBDII bluetooth thing, so I can pull it up on my phone or tablet. Would that get me an accurate number?

Yowen - not necessarily not spaghetti and meatballs > MontegoMan562 is a Capri RS Owner
10/22/2013 at 10:32

Haha yeah. And certain cars should come with a label that says running premium will cost your the same amount of money, or it should at least be advertised more extensively.

Nibbles > Yowen - not necessarily not spaghetti and meatballs
10/22/2013 at 10:33

I don't know! It would depend on the sample rate and refresh speed of the application.

I'm sure it'd be close but nothing beats a gauge directly plugged into your vacuum system lol

Yowen - not necessarily not spaghetti and meatballs > Nibbles
10/22/2013 at 10:36

Yeah, I imagine a real gauge is best. I think depending on how much you spend on the bluetooth device you get a better refresh rate, so I was planning on getting one of the pricier ones/one that is known to have a good refresh rate. At one point I tried out a cheap one and the refresh rate was atrocious, lol. The best way to do it is likely with cord, but I don't think I want that all over my car interior, in addition to car charges and such (but perhaps it also charges the phone.... hmmm).

MontegoMan562 is a Capri RS Owner > Yowen - not necessarily not spaghetti and meatballs
10/22/2013 at 10:37

Yeah because it depends on the car. Some see a decrease in mileage I believe (I did in my old blazer). Only ran it once because the gas station f-ed up and priced it the same as regular so I thought I'd have a little fun and see if it was better or worse in the engine.

Ran great, burned very fast lol.

dinobot666 > Yowen - not necessarily not spaghetti and meatballs
10/22/2013 at 10:39

Around here, there's no ethanol in premium (91) fuel.

Yowen - not necessarily not spaghetti and meatballs > dinobot666
10/22/2013 at 10:49

ah ok, I just did some googling, buying 93 is by no means a guarantee that you are buying ethanol free, it sounds like most cities/urban areas are required to put ethanol in....

Yowen - not necessarily not spaghetti and meatballs > dinobot666
10/22/2013 at 10:50

To make matters worse, my state, Michigan, does NOT have a labeling requirement.

Nuggolips > Nibbles
10/22/2013 at 10:51

Hmm, maybe it was me then... or my choice in gas stations. :)

Anyway, turbo is mandatory for the mountains. I don't have a Saab anymore but my Focus ST with its tiny little turbo just loves it some mountain driving!

dinobot666 > Yowen - not necessarily not spaghetti and meatballs
10/22/2013 at 11:02

Around here, the 89 and 89 pumps have a label that clearly marks them as having a 10% blend of ethanol. The 91 pumps don't have the blend label on them, but who knows, maybe 91 is also ridden with that crap as well.

All I know is that it destroys O2 sensors and catalytic converters. Fucking garbage is all it is.

Yowen - not necessarily not spaghetti and meatballs > dinobot666
10/22/2013 at 11:06

Lol, good thing I am getting rid of 2 of my 3 cat's then.

It is annoying that it's so hard to find pure gasoline anymore...

Hydrochloric > Yowen - not necessarily not spaghetti and meatballs
10/22/2013 at 15:23

Lucky you have that choice! One of the downsides to DIY boosting is that you're pretty much stuck with 93 all the time. My 10:1 CR EJ251 at 5PSI would NOT like anything below that... The knock sensor would probably pull timing so bad it would end up firing after TDC...

Yowen - not necessarily not spaghetti and meatballs > Hydrochloric
10/22/2013 at 15:29

Lol. Once I get a tune I have to commit to a certain octane. I'll be making significantly more power. I'm looking to have a backup tune for 91 octane in case I find myself somewhere they don't have 93.

Hydrochloric > Yowen - not necessarily not spaghetti and meatballs
10/22/2013 at 15:50

Or you find crap 93. In the northeast I do my best to only buy Sunoco 93, I can statistically prove by way of knock count it's the highest quality of the common brands near me.

Yowen - not necessarily not spaghetti and meatballs > Hydrochloric
10/22/2013 at 15:51

I haven't searched very extensively yet, but Citgo near my work is the easiest option for 93. I think their gas isn't so bad, haha.

Hydrochloric > Yowen - not necessarily not spaghetti and meatballs
10/22/2013 at 15:55

Very rarely do I have a chance to see a Citgo, so that may well be. Actually, around me there's primarily only Sunoco anyway. A few Mobil stations, and that's about it. Unless completely unbranded Stewarts gas seems like a good idea...

Yowen - not necessarily not spaghetti and meatballs > Hydrochloric
10/22/2013 at 16:05

We recently got a new brand called Agco, no idea where they get their gasoline from.

Even better, there's an Obama branded gas station in Detroit now.

Hydrochloric > Yowen - not necessarily not spaghetti and meatballs
10/22/2013 at 16:10

I'm afraid to ask what the POTUS-brand station is called...