A car is listed as "Premium Fuel Recommended," we can debate till death if it's necessary, the differences, and results compare to using 87 or 89. Let's try a different angle.

Let's for a second all agree that "Premium" is necessary.

1. What is Premium? 91 or 93? Depends on where you live. If 93 is what is what we should use (standard), then by using 91, it would be the same as going from 91 to 89. Or 89 to 87. The difference is 2. So why do we frown on using anything less than "premium" since the difference is the same as 93 to 91?

2. Many have said you will damage your engine by using less than premium because of ABC, XYZ, etc, etc. Computer can adjust, but still. It's what the Manufacture recommend.

If we use Premium on a car that only requires 87, many will say it's a waste of money. Ok, true. Therefore, why wouldn't using premium fuel on a 87 car actually damage the engine? Because the computer can adjust, so it's ok. If that is true, the reverse should be the same, right?

 

Have you driven a car that requires Premium fuel only?

& to answer your question no.

Nice avatar btw.. lol

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Intense3.2 &raquo;</TD></TR><TR><TD CLASS="quote">Have you driven a car that requires Premium fuel only? </TD></TR></TABLE>

Yes. 06 MB C230. And rode in a C43 (or whatever that number was back then).

 

My car is listed as needing premium fuel but in the owners manual it says you can use regular but tells you it will give you less hp and less mileage and even gives the numbers.

It lists "premium" as 91 or above.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by GoLowDrew &raquo;</TD></TR><TR><TD CLASS="quote">

Yes. 06 MB C230.</TD></TR></TABLE>

Do you notice a difference when you put in anything less than premium?

 

That's deep.

Maybe when manufacturers say "premium only," they're figuring for 91 because of us poor saps in California.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Intense3.2 &raquo;</TD></TR><TR><TD CLASS="quote">

Do you notice a difference when you put in anything less than premium?</TD></TR></TABLE>

What is premium? 91 or 93? Going back to my question, there is a difference by 2 octane. So how is that different from going 91 to 89?


Modified by GoLowDrew at 2:26 PM 7/24/2008

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by GoLowDrew &raquo;</TD></TR><TR><TD CLASS="quote">

What is premium? 91 or 93? Going back to my question, there is a difference by 2 octane. So how is that different from going 91 to 89?</TD></TR></TABLE>

You pose a good question, but maybe 91 is the absolute lowest octane the car can take without loosing performance & a good driving experience. I know that held true for my h22 motor & my acura cl type s.

 

91 seems fine, after all.. that's all they have on the West coast.

From what I have experienced, before I owned my fit, when I put cheap gas in my old Mazda.. I would get poor gas mileage. This makes sense, because if you put cheap gas in a car that requires premium, your ECU is going to retard your timing. Normally when you have retarded timing you're going to have decreased gas mileage.

I guess the only way to tell would be to drive around with a scangauge.

If I don't make sense that's okay.. It's been a long day.

 

I use regular unleaded in my TSX which requires premium, I haven't seen any ill effects as of yet.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by LSVTEC 91 Civic &raquo;</TD></TR><TR><TD CLASS="quote">91 seems fine, after all.. that's all they have on the West coast.

From what I have experienced, before I owned my fit, when I put cheap gas in my old Mazda.. I would get poor gas mileage. This makes sense, because if you put cheap gas in a car that requires premium, your ECU is going to retard your timing. Normally when you have retarded timing you're going to have decreased gas mileage.

If I don't make sense that's okay.. It's been a long day. </TD></TR></TABLE>

decreased timing = decreased power = more throttle to maintain the same driving habits = more fuel used


Its very very noticeable in cars that require premium fuel to run effectively on my speed6 it said to use 91 always unless of an emergency.... well one time when it was empty I put in 2 gals of 87 to see how it would run; it ran like dog ****. Motor would shutter through out the rpm range, if there was any boost at all the CEL would pop on and it would fall on its face. Usually on my turbo cars on the way to work and school I would fill up with 87 due to the fact that I KNEW i wouldn't be flooring it and 91 would be a waste. (and at the time 91 was 1.59 so 30 cents was a big diff)

So key note if its a direct injection motor, use the gas it says. Also cars with higher compression or if you go positive manifold pressure while driving normal.... use 91

 

Premium = 91+, not necessarily the highest octane you can buy at the pump.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by GoLowDrew &raquo;</TD></TR><TR><TD CLASS="quote">

What is premium? 91 or 93? Going back to my question, there is a difference by 2 octane. So what is that different from going 91 to 89?</TD></TR></TABLE>

Yes, there is. Octane is a measure of anti-detonation of a gasoline or fuel.
There is no performance gains if you do not need it OR MPG gains. You would get more power AND MPG from lower octane if your engine can use that lower octane.

 

This isn't all abstract. You choice of fuel becomes more important with increasing compression and engine speed.

 

People who cheap out and pump regular in a car that requires premium are morons. Spend the extra $5-6 bucks a tank so you don't have to worry about knocking/pre-detonation.

 

You really couldn’t compare anything. I run 93 and think it runs better, but I have never tried running 91/89 for a month to really compare. I know a lot of people who cheap out simply because they never experienced better so their standards are very low. It is all about how you view reality, guys like to think they are scientists or some ****, when most of the time the only evidence you pay attention to is whatever supports the outcome you have already decided on.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by GoLowDrew &raquo;</TD></TR><TR><TD CLASS="quote">A car is listed as "Premium Fuel Recommended," we can debate till death if it's necessary, the differences, and results compare to using 87 or 89. Let's try a different angle.

Let's for a second all agree that "Premium" is necessary.

1. What is Premium? 91 or 93? Depends on where you live. If 93 is what is what we should use (standard), then by using 91, it would be the same as going from 91 to 89. Or 89 to 87. The difference is 2. So why do we frown on using anything less than "premium" since the difference is the same as 93 to 91?

2. Many have said you will damage your engine by using less than premium because of ABC, XYZ, etc, etc. Computer can adjust, but still. It's what the Manufacture recommend.

If we use Premium on a car that only requires 87, many will say it's a waste of money. Ok, true. Therefore, why wouldn't using premium fuel on a 87 car actually damage the engine? Because the computer can adjust, so it's ok. If that is true, the reverse should be the same, right?</TD></TR></TABLE>


Would you like a ride in my 91 octane tuned FP Green WRX STI?..i think u need a manly hugg

 

Mrs. Splat's S40 wants premium. She tried alternating tanks between 93 and 89 for about a month, mileage was about 1-1.5 mpg lower with 89.

Even with today's prices, that's a $1.20 a tank. She's back on 93.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Splat &raquo;</TD></TR><TR><TD CLASS="quote">Mrs. Splat's S40 wants premium. She tried alternating tanks between 93 and 89 for about a month, mileage was about 1-1.5 mpg lower with 89.

Even with today's prices, that's a $1.20 a tank. She's back on 93.</TD></TR></TABLE>
Interesting. Mrs. Sans has a V70 (2.5t) that requests midgrade. It doesn't like regular when I drive it, but I wonder if premium would improve mpg? Alas, I live in an area that is impossible to experiment in -- too many traffic variables.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Mark sans &raquo;</TD></TR><TR><TD CLASS="quote">
Interesting. Mrs. Sans has a V70 (2.5t) that requests midgrade. It doesn't like regular when I drive it, but I wonder if premium would improve mpg? Alas, I live in an area that is impossible to experiment in -- too many traffic variables.</TD></TR></TABLE>

Matters what the ECU is mapped for. If it says mid-grade, that is probably the best to run.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by LSVTEC 91 Civic &raquo;</TD></TR><TR><TD CLASS="quote">91 seems fine, after all.. that's all they have on the West coast.

From what I have experienced, before I owned my fit, when I put cheap gas in my old Mazda.. I would get poor gas mileage. This makes sense, because if you put cheap gas in a car that requires premium, your ECU is going to retard your timing. Normally when you have retarded timing you're going to have decreased gas mileage.

I guess the only way to tell would be to drive around with a scangauge.

If I don't make sense that's okay.. It's been a long day. </TD></TR></TABLE>

i agree with this statement, seems like i get better MPG using chevron, mobil and shell gas.

 

The gap between each grade is only .10 cents. It's always been that way since gas was .85 cents a gallon. So considering today's gas prices, that .10 cent increment is a bargain.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Turbogixxer &raquo;</TD></TR><TR><TD CLASS="quote">

Matters what the ECU is mapped for. If it says mid-grade, that is probably the best to run. </TD></TR></TABLE>


I concur, manufacturer's recommendation is best. The old adage of "use the lowest grade you can run w/out knocking/pinging" isn't really applicable to cars with knock sensors.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Mark sans &raquo;</TD></TR><TR><TD CLASS="quote">
Interesting. Mrs. Sans has a V70 (2.5t) that requests midgrade. It doesn't like regular when I drive it, but I wonder if premium would improve mpg? Alas, I live in an area that is impossible to experiment in -- too many traffic variables.</TD></TR></TABLE>

Huh, I thought all the whiteblock turbos wanted premium. Mine does, but it's HPT. I don't know how much boost her 1.9T is good for, but the book says premium. It must be sized just right, because she gets 31 mpg out of the thing

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Turbogixxer &raquo;</TD></TR><TR><TD CLASS="quote">

Matters what the ECU is mapped for. If it says mid-grade, that is probably the best to run. </TD></TR></TABLE>

I wouldn't run premium in anything that didn't call for it, either. Mrs. Splat did lose mileage on hers, I guess it pulled a little timing under load.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Splat &raquo;</TD></TR><TR><TD CLASS="quote">I wouldn't run premium in anything that didn't call for it, either. Mrs. Splat did lose mileage on hers, I guess it pulled a little timing under load.</TD></TR></TABLE>

Well, if the ECU is mapped for low grade and you put 91+ in there, the knock sensor will not do anything.