SaabCentral Forums banner

1 - 20 of 22 Posts

·
Registered
Joined
·
14 Posts
Discussion Starter #1
I have 9-2X aero, find that gas mileage of our car is very low.
I just want to know if everyone here is using 92 gas?
Can we run 89?

Thanks.
 

·
Registered
Joined
·
86 Posts
RedAero said:
I have 9-2X aero, find that gas mileage of our car is very low.
I just want to know if everyone here is using 92 gas?
Can we run 89?

Thanks.
Your ECU is smart. It knows when you put crap gas in the car and it will run a "bad gas" ignition timing/fuel map. Feel free to put 89 octane in your car, but be prepared to kiss around 20hp goodbye.
 

·
Registered
Joined
·
30 Posts
jdmpartstx said:
Your ECU is smart. It knows when you put crap gas in the car and it will run a "bad gas" ignition timing/fuel map. Feel free to put 89 octane in your car, but be prepared to kiss around 20hp goodbye.
Your ECU is smart, BUT, you'd be running the car (ignition) retarded, meaning it'll run hotter, and fuel milage and throttle response even part throttle will be worse. The added heat will NOT be good for the exhaust or turbo hot side. Don't run 89 on a regular basis. If you've been following the NASIOC thread on '04 and '05 WRX's (which is the same software as our 9-2x Aeros) Subaru has a 2 second full throttle enrichment delay to meet some EPA standard. This make the car especially detonation prone when you get full on the throttle at higher RPMs. If you NEED the power (such as trying to get away in an emergency situation), you'll be running the car at the edge of detonation for 2 seconds. It's up to you,
but DON'T DO IT! If you must save $$$, mix 93 with 89 half and half to be safe.

Scargo
 

·
Registered
Joined
·
14 Posts
You shouldn't assume someone is tight just because they're trying to save some money. As high as gas prices are now adays, there's nothing wrong with being economic minded.
 

·
Registered
Joined
·
89 Posts
You shouldn't assume someone is tight just because they're trying to save some money. As high as gas prices are now adays, there's nothing wrong with being economic minded.
Until you detonate an engine.

Of course, you could have saved another $3000 if you had bought a Linear. That would buy you almost 100 tanks of gas, at the cheap gas prices.


There should be at least a couple places that sell 91 octane around you, of course, that might not save you that much money over 93.
 

·
Registered
Joined
·
14 Posts
There are no places around here, and I mean none that have 91 octane. I use 93 most of the time, if anything, I'll only mix if I'm going to take a long drive but I always make sure my tank is over half way full with 93 octane gas. Someone correct me if I'm wrong, but the main reason I do it is because if the car requires 91 octane, and my tank has more then half a tank of 93 octance and I fill the rest (which is less then half a tank mind you) with 89, wouldn't the car be alright? If I'm wrong that's fine, but I doubt this would cause detonation. Now If I used 89 more so then 93 then I could understand.
 

·
Registered
Joined
·
86 Posts
If you do the math, it's silly. It's really not worth the risk of detonation to put anything other than 93 octane in the tank.

For example:

Let's say 93 octane is $2.29/gal and 89 is $2.19/gal - these are realistic prices in Texas today.

You mentioned that you never let the tank get below 1/2 full - so let's assume you top it off twice a week, alternating each time between 89 and 93 octane with the intent of keeping about a 91 octane mix in the tank.

Your car has a 15.9gal capacity tank. Each fillup is 7.95 gal.

When you fill up with 93 octane it costs you $18.21
When you fill up with 89 octane it costs you $17.41

So each month it's costing you $142.48 in gas.

If you filled up with 93 octane EVERY time it would cost you $145.68.

So you're saving a whole $3.20 per month or a whopping $38.40 a year on gas by mixing 89 and 93 octane, instead of just using 93 octane.

To me, that's not worth the risk of detonating.

For what it's worth - in my experience (and in the experience of the experts who tuned my car) Citgo has the best gas in this area. The stuff you can get at 7-11. For whatever reason, the cars that are dyno tuned on Citgo 93 octane are much better behaved, timing-wise, than those on other fuels. Also, the Citgo by my house offers 5 grades of gas and 91 octane is one of them. I still stick with 93 :)
 

·
Registered
Joined
·
14 Posts
jdmpartstx said:
If you do the math, it's silly. It's really not worth the risk of detonation to put anything other than 93 octane in the tank.

For example:

Let's say 93 octane is $2.29/gal and 89 is $2.19/gal - these are realistic prices in Texas today.
I don't know what part of Texas you're from (the only thing silly is your guesstimation in gas prices), but that is far from realistic. There is a 8cent to 10cent price difference a gallon between 89 and 93 octane and like I stated, I don't do it all the time but there are times where I have to do a lot of out of town driving for work so it does make a difference. :)
 

·
Registered
Joined
·
86 Posts
AeroSpeed said:
I don't know what part of Texas you're from (the only thing silly is your guesstimation in gas prices), but that is far from realistic. There is a 8cent to 10cent price difference a gallon between 89 and 93 octane and like I stated, I don't do it all the time but there are times where I have to do a lot of out of town driving for work so it does make a difference. :)
Read it again. I estimated a 10cent difference in price per gallon between 89 and 93. I didn't say that your scheme of trying to concoct 91 octane gas doesn't make a difference. I'm just saying that the difference is negligible which can clearly be seen if you do the math.

If you're mixing 89 less frequently, then your savings are LESS than what I stated above. Is it really worth risking damaged ring lands and exessive blow-by to save less than $40 a year?

You stated that your goal was to save money on fuel. Again, I say the best way to do this is to continue to use 93 octane and just moderate your use of the throttle. Do an experiment. Calculate your gas mileage with your normal driving habits, then calculate it when you never let the engine rev above 4000rpm and never go more than 50% throttle. You'll see a drastic difference.

I'm in Dallas, tx.

And I got the estimated prices from here - http://www.texasgasprices.com/
 

·
Registered
Joined
·
89 Posts
This argument is almost as bad as the guy who said 1% financing was better than the rebates. Its 100 against 1.
 

·
Registered
Joined
·
14 Posts
Allright, allright..I'm learning guys so cut me some slack, it wasn't my intent to start an arguement. I'll more then likely need you guys to help me in the future so let's move on shall we (and yes I will use nothing but 93 octane from now on..) ;)
 

·
Registered
Joined
·
16 Posts
qcomdrj said:
This argument is almost as bad as the guy who said 1% financing was better than the rebates. Its 100 against 1.
Update on this for you.

I know this isn't the correct message list for this but, Saab made a mistake in my favor when proccessing my loan. Because I have the signed contract and everything has been proccessed, it cannot be changed.

If you noticed from one of my messages I stated and someone also quoted me saying this, I did not know how it worked because the numbers didn't seem right to me either, however I was not going to argue about it. I got one hell of a deal.
 

·
Registered
Joined
·
89 Posts
omahawk,
If that is the case (ie, the loan guy crunching the wrong numbers) then I rescind my previous statements about you getting hosed. It was Saab who got hosed. Had you actually gotten the payments you were supposed to, maybe then you would have paid more money.
Maybe he accidentally gave you rebates and 1% or something. Who knows, but it is good that you went back to see if everything was legit.
And this is what forums are for.
Oh, and I wasn't using that example because I thought you were being belligerent in that thread or anything, the only reason I mentioned it is because the numbers are about the same. You were a lone voice, and everyone else was saying something different, showing math, etc.
 

·
Banned
Joined
·
5,841 Posts
Gas is cheap for you guys in the Americas.

In Scotland is 87.9 pence a litre and climbing.

Thats well over $7.25 dollars a gallon.
 

·
Registered
Joined
·
10,348 Posts
I feel for you Shadow. It makes me sick when Americans cry about how expensive gas is. "I'm trying to save money on gas".
Pffft. Buy a hybrid then.
Americans SHOULD be paying even more for gas.
I fill my tank in Ohio it's $35. I filled my tank in Ontario Canada and it was almost $50. In the UK it would be at least $65.
I use ONLY the highest octane the gas station has, price be damned.
 

·
Banned
Joined
·
5,841 Posts
I should be working and I am on this forum again!

I just did the maths and my gas tank is 68 litres

Divid 68 litres that by 4.5,( a single gallon) gives
15.1 gallons in total.

muiltply 15.1 by $7.25 which is the fuel cost in Scotland right now and will climb very soon!
This means to fill my tank from the feet up would cost $109.55:eek:

That would give me around 280 miles if i drive like a granny.

I am so glad i dont own a 5 litre muscle car:cry:

You know the goverment taxes the fuel over here like 80% or more i think.

We even have a window tax on buildings, beat that:lol:
 
1 - 20 of 22 Posts
Top