Colorado Guy AF Ret.

That's one of the biggest mistakes in terms of wasting money with perceived better results.

Ask ANY engine designer and engineer and they will tell you that if the car is designed to burn 89-91.....that 93 won't give you any appreciable results. In many driver's minds all across this country....no matter what they drive....they think...."Oh, if my car says I should burn 87 then 91 would be so much better." It's blatantly false. Period.

In these folks minds....they "feel better" burning more expensive gas, then good for them....but, the vehicle says.."I was running at top designed efficiency with the grade I was designed for."

That you can take to the bank....oh, you can't since you are wasting the extra money on gas you don't truly need.

I'm just giving you the facts....if you truly can dispute them....with professional testimony, then show me/us. Not just what you think.

Otherwise, if it makes you "feel better" then do it. The gas companies will love you even more.

QN52

You're such an ass in your posts.

Mikey Dallas

I buy my gas at Costco. They have 89 or 93. It costs me less to buy the 93 there than 91 at a regular station. That said, I am beginning to think you have a bit of a chip on your shoulder. I have tried to just ignore you, but dude, maybe you should up your meds...

Colorado Guy AF Ret.

That's the best you can come up with??
You're an ass for being ignorant and not bringing forth anything useful. Dispute my facts and we can talk....otherwise don't waste your time with your bullying. It won't work.

Think of something you can contribute with...whether some agree or not. That's what we're here for and that's what I did.

Colorado Guy AF Ret.

Well, DUDE.....you're out in left field since you don't know what your talking about. Maybe you need meds. Personally I'm doing just fine. Bullying me won't work....so save your BS comments for something constructive.

I gave you facts....come up with your own that support the need for premium 93...other than cost cheaper?? Whatever. My facts are correct. So, since you can't come up with anything else....guess you just don't have the brain power that is needed.....other than throwing out name calling. Get off here if that's all you can do if you disagree with someone.

TLtrigirl

iTrader: (1)

sorry...totally missed your post...

after having a '12 RDX as a loaner, and sat and seen the '13 in person...

the new RDX is much more refined than the last gen. the grill is much more integrated (though i'm still not completely sold on the new look....it has grown on me) rather than slapped on the front of the car. the cargo area is tiny compared to the MDX. i've pulled up next to RDXs before and the MDX makes the RDX look like a puppy. after having seen the cargo area and having driven the 12 RDX...i'm reassured that i made the right choice with the MDX to meet my needs. the RDX would have been a bit tight. it's a nice looking car. that turbo was zippy as hell! i'm sure the V6 in the '13s drives similarly to the other V6's in the acura line up. the new RDX is certain to have it's market and fans and should sell well. the ILX on the other hand.../OT

the interesting thing for the gas debate in the NEW RDX would be to have people post long term results of using regular vs premium to see what differences (if any) folks are seeing.

type of fuel, avg mph (no i drive 30% city and 70% hwy, or i drive mostly city/hwy this info doesn't really; we need the AVG MPH for the tank), and MPGs.

BillyEngineer

To all our American friends in Canada 91 Octane can be as much as $0.18/liter more or 68 cents a gallon. on a 70 liter fill up its another $12.60. In my previous Acuras i tried mid grade but the performance just wasn't there. you bought a performance vehicle so suck it up and put in the "good stuff"

weather

Billy...I am so glad we have Costco where I live....the difference between reg and supreme is always a static 6 cents/litre so at 70 litres, this is about 4.30$ but I will never see my tank go lower than 60 litres so about 3.60$ a tank X 4 tank a week which is about 15$ a month. I wouldn't want to have to pay 18 cents more a litre for supreme.....ouch!

Sculldog3

This thread seems to have gotten a lot more interesting!! Wondering where the moderators are...thought this stuff was frowned upon...

So...there is an easy and obvious retort on this...that speaks directly to taking money to the bank...and being fiscally sound...where the loses involved grossly outweigh any sort of losses from spending pennies per gallon..sort of suprised no one has seen this or borught it up....

Adding gasoline (93 octane) to the fire...just doing my part!!

Sculldog3

P.S. Also filled up at Costco for the first time this week, and went with the 93 as well. A tour of local stations in my area seems to show that their price for the 93 is at or lower than what others are charging for 91, so while I won't benefit from the extra octane, it's not in fact costing me more than I'd otherwise spend, since I'm thinking I'll follow the Acura recommendation, at least for now.

njdman

I just picked up our new 2013 RDX and the salesman I was dealing with said flat out "regular" without hesitation what grade to burn. This was when I was picking the car up, and all paid and ready to go so it wasn't a selling point issue. He also said this is the only Acura that "recommends" premium and does not "require" it. That said I will run mid grad 89 for the first 1000 miles and see how the mileage performance is. We have a 2012 T6 Volvo that is a turbo (300HP) and never run high test. Regular is the fuel used and never a problem over the past 9 years and 3 Volvo's, all 6cyl, all turbos, all say "premium recommended" but not required. My brother in law has a 2004 TSX with 170,000 mile, 6 speed manual, and has run regular since day on, never a problem.

diamondcut

I love Timmy's

RDX FAN

Just purchased a 2013 RDX AWD w/Tech pkg last week. Will be checking in on this thread.

geocord

My understanding is that the reason Acura recommends premium is for higher performance....not MPG as the MPG will probably be so little a difference that it would be unnoticeable. However, premium is supposed to provide peak HP and by peak I mean just a few HP more than running regular and the average person would probably not notice the difference unless they were running 0-60 time trials regularly.

I plan on trying both to see if I can tell any substantial difference in pickup when I really apply the gas. If not, I will obviously default to regular. In the Chicago area midgrade is about .15 to .20 more a gal than reg and prem is about .25 to .35 more than reg. To all the people that say "well, you bought a $40k car so why worry about a few extra bucks per fill up", I say, the reason I can buy a $40k car is because I save money when it makes sense to save money and I don't throw it away for no good reason.

AmberB

I'm in the Chicago area too...hey neighbor....

I'm pretty sure your're 'right' about the performance but the technical detail you may be missing is the "why". Higher octane gas is more stable so it's less likely to pre-detonate under heat and pressure on the down stroke in the engine. That stability allows the engine computer to advance the timing which results the the performance gains you speak of.

The flip side to this is that lower octane gas is less stable...once the computer senses lower octane gas in being used it will retard the timing to protect against detonation (ping). Once the timing has been adjusted downward the performance will suffer. Retarded timing will also adversely affect fuel economy.

So if you switch from 93/91 down to 87 why do some people report no change in fuel economy or performance? I suspect they simply haven't driven the vehicle under conditions that will initiate detonation and cause the computer to retard timing, yet. Given the class of vehicle we're discussing it 's quite possible that it will never cause an issue for some % of the ownership here as we tend to be a more mature, cautious bunch.

I may be wrong, feel free to correct me, just my understanding of how this all works.

Vividsi

there should be a poll as to who would use premium in this car vs regular.

Colorado Guy AF Ret.

There are many vehicles on the market that "recommend premium." The real reason is for performance.
If 91 is recommended then you can use 89. The computer WILL adjust and there will be no issues. I would NOT go down to 87. It has been shown that fuel mileage will not be affected if this is followed.

Doubt me that's fine...but, this comes straight from Honda Motor Corp. and I've owned many, many cars, SUV's etc. And I used to teach internal combustion engines...gas and diesel....and taught aircraft jet engines to customers around the world. I think I have the background to state my case. Most folks on here are well intended but, don't have the tech. background to back up their "assumptions." And that's OK, that they aren't properly schooled, but, the really unknowing don't get the right info.

geocord

I may be wrong, feel free to correct me, just my understanding of how this all works.[/quote]

I don't have the tech understanding that you do so I certainly couldn't correct you. I guess I didn't really "miss" the reason it's just that it didn't matter "why" so much....just the results. But, what you say makes sense. I also have a Mazda and have spent a lot of time during oil changes shooting the sh** with the service writer at my Mazda dealership. He has a ten year old TL that is absolutely cherry and he says that he has always burned regular in it. He ran a few tanks of premium one time and didn't notice any change in MPG. Now this is a totally different vehicle and it is ten years old but I trust what he's saying.

The real question is, how much would performance(gittyup) be affected and would MPG be affected much if driven fairly aggressively. I'll probably be testing out both when I get my RDX(probably next week) after the breakin period of course.

AmberB

I don't have the tech understanding that you do so I certainly couldn't correct you. I guess I didn't really "miss" the reason it's just that it didn't matter "why" so much....just the results. But, what you say makes sense. I also have a Mazda and have spent a lot of time during oil changes shooting the sh** with the service writer at my Mazda dealership. He has a ten year old TL that is absolutely cherry and he says that he has always burned regular in it. He ran a few tanks of premium one time and didn't notice any change in MPG. Now this is a totally different vehicle and it is ten years old but I trust what he's saying.

The real question is, how much would performance(gittyup) be affected and would MPG be affected much if driven fairly aggressively. I'll probably be testing out both when I get my RDX(probably next week) after the breakin period of course.[/QUOTE]

So, I'll bug you with the "why" again as to why the Dealership guy with a TL noticed no change in MPG with premium. The computer doesn't know what kind of gas you put in. It only knows if the engine detonates under acceleration. If it senses detonation it makes countermeasures to prevent the condition (retards the timing.) Once the timing has been retarded the guy puts in premium gas again. Again the engine doesn't know this happened and continues to run on the retarded timing setting. So he doesn't notice any difference in mpg because nothing changed. It may take more than a few fill ups for the engine computer to reset back to the default setting with advanced timing. How many it takes, I don't know. Maybe the Mazda guy knows, or has a resource he can ask.

I can say I drove a 2003 G35 for the past nine years and I would switch between 93-89-87 depending on my mood and the pocket lint/cash ratio in my pants. I have a very consistent driving style and my mileage was always in the 19-21 mpg range. Was this due to octane? I don't know. It was a factor but so are weather, traffic, drive thru window waits, train crossings, and number of encounters with the righteous ahole in the left lane who's "right" for driving the speed limit and holding up everyone else.

You're right we need to do some testing. MPG will be easier to document over seat of the pants performance shy of going to the drag strip and running the 1/4. I'm in for documenting my mileage with both 87 and 93. I buy gas at Costco so I can't test 89. I'm on the dealership fill right now and I don't know what they used.

Another factor that affects us Chicago folk making our numbers possibly not follow with other folks...stupid special blend gas.

geocord

What you say is very true. I don't buy at Costco(am a member though) cause I refuse to get another credit card to carry around so I pay cash in the store. Plus it's not that close to my house so the "need gas" and "trip to Costco" rarely intertwine.

That's a good point about the Chicago blend as it affect MPG differently in different times of the year. Another factor is ethanol mix. If you're lucky enough to live in an area where you can get the unaldulterated juice it could gain you an extra one-two MPG. I don't know how far I'd have to travel outside of the Chicago area to get the good stuff but suffice it say that it would be counterproductive unless I was going that way anyway.

I gather from what you're saying that any comparison would have to done over many tankfuls and possibly in the same season(Chicago anyway). I drive a 2002 Infinit QX4 which I will be trading in. Been a great vehicle and still has lots of productive miles left in it. But I don't need all the AWD, 4WD, 4wdLo capabilities it has nor the accompanying low MPG which Infinitis are kind of known for. Plus it's just time for some new tech and such.

Colorado Guy AF Ret.

I don't have the tech understanding that you do so I certainly couldn't correct you. I guess I didn't really "miss" the reason it's just that it didn't matter "why" so much....just the results. But, what you say makes sense. I also have a Mazda and have spent a lot of time during oil changes shooting the sh** with the service writer at my Mazda dealership. He has a ten year old TL that is absolutely cherry and he says that he has always burned regular in it. He ran a few tanks of premium one time and didn't notice any change in MPG. Now this is a totally different vehicle and it is ten years old but I trust what he's saying.

The real question is, how much would performance(gittyup) be affected and would MPG be affected much if driven fairly aggressively. I'll probably be testing out both when I get my RDX(probably next week) after the breakin period of course.[/quote]

Ok...here goes. I can tell you that unless you are doing 1/4 mile runs you will not notice a performance drop....or most likely will not. I always have to allow for "exceptions" for those that think or feel there is one.

Burning "regular" is one thing...but, the octane and additives based on where you are in the country all make a difference. I will stand by my original offerings. If 91 is recommended, then dropping to 89 will work. I would not drop to 87. It MIGHT work, but, Honda says and Acura says...NO! It's too chancy that you won't hear the pre-detonation or "pinging" and over time harm will come to your engine. It's not worth the little saved in fuel cost.
If a person can afford the RDX they can afford 89 or 91 fuel. Just take the cost differences and do the math for the extra cost or savings per month and for the year. It's not that great a difference. IF a person is on that tight a budget they shouldn't be driving a $40K SUV.

If 89 is not available where you buy, then find where it is. Again, the little in savings is not worth messing with the results of low grade fuel. If you can't find 89 at all, then my choice is put in the 91. Not worth it to not do so if 89 is not around.
Personally, in my RDX, I put in the 91 so I can realize the full potential of the engine. I know I don't have to...but, that's just me. I'm a hot rodder since age 16.

Engine computers and fuel management systems don't take very long to adjust to a different octane. To do the "test" you will need to run the tank of higher octane down as low as you dare....and then fill with the next lower octane. Run that tank out and refill with same. It will be adjusting by then.
Did you know that fuel is blended at the pumps to make certain octanes?? True. 89 is a blend of 91 and 87 done at the station. 50/50 from each underground tank is put into your tank as you fill. Refineries don't "make" 85,87,89, 91, 93. They blend when they can at the pumps.

So, if you have 91 in the tank and want to put in 89 then you'll have to wait for results until you know the 91 is fully out of the tank and only 89 is remaining.

AmberB

I had a QX4 too. It died when uncle sam ran silica through the engine after I traded it for $4500 under the cash for clunkers incentive. That was a nice truck.
189K miles with NO problems, ever. I traded it for a mazda tribute. Nice on gas but a total pos relative to the comfort afforded by the QX4. Now the Tribute sits in my driveway and I drive the RDX. Huge difference in comfort and better mileage too. You won't be disappointed. Where are you buying?

Sorry for the OT....

geocord

Just got back from seeing the premier of "End of Watch". Great cop movie, best I've seen in a long time.

Anyway, yes the QX4 has been great but only has low 90s in mileage so it was worth too much back when the cash for clunkers was going on and I wasn't ready then either. I'm looking at Libertyville Acura if we can come to terms on price. No financing involved and no incentives so should be a pretty straight trade-in deal.

geocord

Ok...here goes. I can tell you that unless you are doing 1/4 mile runs you will not notice a performance drop....or most likely will not. I always have to allow for "exceptions" for those that think or feel there is one.

Burning "regular" is one thing...but, the octane and additives based on where you are in the country all make a difference. I will stand by my original offerings. If 91 is recommended, then dropping to 89 will work. I would not drop to 87. It MIGHT work, but, Honda says and Acura says...NO! It's too chancy that you won't hear the pre-detonation or "pinging" and over time harm will come to your engine. It's not worth the little saved in fuel cost.
If a person can afford the RDX they can afford 89 or 91 fuel. Just take the cost differences and do the math for the extra cost or savings per month and for the year. It's not that great a difference. IF a person is on that tight a budget they shouldn't be driving a $40K SUV.

If 89 is not available where you buy, then find where it is. Again, the little in savings is not worth messing with the results of low grade fuel. If you can't find 89 at all, then my choice is put in the 91. Not worth it to not do so if 89 is not around.
Personally, in my RDX, I put in the 91 so I can realize the full potential of the engine. I know I don't have to...but, that's just me. I'm a hot rodder since age 16.

Engine computers and fuel management systems don't take very long to adjust to a different octane. To do the "test" you will need to run the tank of higher octane down as low as you dare....and then fill with the next lower octane. Run that tank out and refill with same. It will be adjusting by then.
Did you know that fuel is blended at the pumps to make certain octanes?? True. 89 is a blend of 91 and 87 done at the station. 50/50 from each underground tank is put into your tank as you fill. Refineries don't "make" 85,87,89, 91, 93. They blend when they can at the pumps.

So, if you have 91 in the tank and want to put in 89 then you'll have to wait for results until you know the 91 is fully out of the tank and only 89 is remaining.[/quote]

Yes, I know all about the blending. Grew up with gas stations in the family and my dad worked for Sunoco for thirty years. I think, but am not sure, they started the super blending with about 7 different concoctions but not sure if the were the first or not. I know they used to have have a lever on the pumps to select the exact grade you wanted. Don't know if they still have because they aren't in my area of the country anymore.

Yes, like i said, I would run several straight tanks of one then several straight tanks of the other to get an average MPG for both and to let the computer adjust completely. Also, I haven't read the manual obviously since I haven't purchased yet so I don't know what it says exactly. I'll trust what the engineers who designed and tested the engines say. If they say you can burn regular gas then I'll take their word for it.

AmberB

I just did a Friday fill...drove all weekend and refilled Sunday night. 93 octane...level roads...light suburban traffic 22.7 mpg. I drive no more or less agressive than other drivers around me.

PaulAWD

I have a 2004 MDX and I ran 87 gas on the highway to Disneyland and my gas mileage stunk. I refilled with 91 and got a few more miles per gallon with the same steady driving. It ran fine without pinging but the mileage suffered.

smarty666

Premium, Premium, Premium!!! Oh, btw, did I mention Premium!

weather

smarty.....What do you run again? (lol)

I am like you.....for me, 3$ a tank (or ~12S a month) is not even worth thinking about it. I put much more octane in my body (Tim Horton coffee) a month!

smarty666

ROFL! Plus, not sure where you are, but here in the NJ, there is only 87, 89, and 93 octanes. The difference in price between premium and mid-grade is ten cents a gallon. Is it really worth it so save an extra $1.60 a fill up by getting mid-grade, lol. Plus, I've never had any luck running regular in an Acura. Too much idling issues, knocking/pinging, and general hestiation by the engine. Almost as if the car was saying, ewww yuck

Plus, if I wanted regular, I would have gotten a Honda.

weather

^^^ exactly!

CoachRick

Well, this new guy might as well jump in here...
Plenty of discussion over at SwedeSpeed re: octane grades in the Volvos, particularly the turbos. We've had 7 Volvos, all with turbos and have run plenty of 87 through them since Volvo quit 'recommending' mid-grade back in '04 or so. In 56K miles in our XC60 T6, we got our best mileage reading using 87(plenty of other factors could be at play, of course) and never could 'feel' a difference in performance between 87 and 93 or anything in between. Same for the less powerful Volvo engines we've had...5 were the 2.5l turbo engines ranging from 197-227 hp. The only time I absolutely went for 93(no 91 around here) was when climbing mountains or running fully loaded(no towing for us in any vehicle, so far).

Never heard a ping, knock or anything similar from any octane grade over ~300K miles. With only 1600 miles on our RDX, I haven't noticed any variation in performance or mileage with tanks of 93 vs 87.

So, what shall I use? Those who discount the actual cost of running 'premium' vs 87 'might' consider the total dollars spent on fuel in a year, for example. For us, two vehicles running ~1000 gal/year each would spend $600 more per year to buy premium vs 87(provided there is no difference in mileage...as is the case with us, so far). Saving $600 is like someone making a car payment for me...nothing to sneeze at. It's like saying you don't care about the 8-12% (or more)improvement in mileage vs our XC60...I much prefer averaging 21-22mpg vs the 19 overall we got in the XC. Of course, I'd rather average closer to 25, but we haven't taken any long trips in the RDX. Much of our central Texas driving is done on 60-70mph 'highways' with stop lights every few miles. That sort of rapid speed change doesn't make for great mileage, so I can't complain about the low 20s in our FWD RDX.

As I've mentioned over at SwedeSpeed, I'm old enough to remember when 'Premium' gas was Amoco 'white' gas that appeared to actually be a premium fuel, quality-wise, as well as having higher octane. I think the overall quality of consumer fuels has 'evened out' at a higher level in the past couple of decades(minus that pesky ethanol stuff ). However, I do still seek out fuel containing a higher amount of additives for fuel system cleaning; for example, Chevron and Shell(not too much Texaco or Exxon around here...no BP at all). As such, my trips to Costco for fuel are few and far between, as they say. IF I find the RDX does perform better on higher octanes, I might consider mixing Costco 93 with a lower grade Chevron or Shell fuel to get the 'best' of both worlds.

Sincere apologies to those folks in Cali who are paying $4.50 and up for a gallon of fuel. We're ranging in the mid-three-dollar area with a full .30 difference between 87 and 93 octane. So, IF I get the 10% bump in mileage vs the Volvo AND can continue to run 87-89, I'll certainly enjoy the 'free' payment or so being made each year by my vehicle choice.

boogerdood

Just did 600 miles to and from the Bay Area to tahoe...lots of elevation, 28.5 mpg on 87 REGULAR. It runs just fine.

njdman

Same mileage as premium, same perceived power. Note the word perceived because I don't think anyone will be able to tell 5 HP to 10HP difference between premium and regular, if it is in fact that much less HP? I didn't mind spending the money on the RDX but I don't like needlessly wasting money on gas not required and I was told by the dealer regular is fine without any hesitation or questions. To put premium in a car because you feel it's a "premium" car and deserves the best is nuts. The wife drives a 2012 $47K Volvo T6 AWD which I think is a fairly "premium" car and it runs regular just fine. And oh yea, the passenger seat actually adjusts for height. The one thing that just might have me trading this 2013 sooner than later, is they cheapened the passenger seat to a basic low grade 2 way power car version. That wasn't very premium of Acura and I really don't believe these RDX's are true "premium" cars, just a jazzed up CRVs which is all I needed.

boogerdood

I was nodding until that last line. These two cars are quite different, and I'll leave it at that.

One thing Id like to see in trying premium next tank, is if i get smoother idling. Currently, its not rock solid smooth at idle, a little vibration, with or without AC on.

smarty666

This is some of the stupidest comments I've read as of late. I've consistently seen a decrease in mpg going from Premium to Regular, plus excessive idling and hesitation from the engine. You want to be a fool and put regular in go right ahead. I'm coming from practical experience.

Plus, if you think the RDX isn't premium and just a jazzed up CR-V, then why the hell didn't you just get a CR-V. You contradict yourself in your own sentence, lol. Just shows me you know nothing about cars when you make stupid statements like that.

Next time, save your money and buy a honda.

aks1972

I dont understand this! People are willing to spend 40K on a car but hesitant to put 200-300 worth of premium gas per year.

At current rate I am consuming 10gals of gas a week. At 0.30 difference between premium and regular it is only 3 dollars a week or 156 dollars a year.

I think I have wasted more on electricity while reading this thread!!!

smarty666

Agreed. There logic escapes me as well. Plus, to say Acura is not a Premium brand but a jazzed up Honda, but you got the Acura b/c it was nicer is just completely contradictory.

geocord

Don't understand all the hostility towards people that want to use regular. Just because someone buys a RDX doesn't mean they want to spend more on gas than they have to. That's logical. I mean part of the reason I bought a RDX was because it gets the best MPG for V6 in it's class. But that only saves me a few dollars a week so I guess that was a stupid reason to pick the RDX because I shouldn't care if I spend a few extra dollars a week. If somone says they are getting good results with regular and Acura dealers tell customers it is fine to use it why does it seem to upset so many people? From what I've read in different forums Edmunds, here etc it seems to be no problem one way or the other. Again, why all the attacks on people in a forum where people are just reporting their results for others to make their own decision? Seems counterproductive.

Yumcha

I do what the owner's manual tells me.

smarty666

Why all the attacks on people who are using Premium in the RDX? Its not a one way street as you try to make it out to be. I was posting my own personal experience with using Regular in Acura products and how it caused a decrease in mpg and rough idling. If people are putting in regular and don't notice this, then they really don't give two shits about cars and can't tell the difference between a rock and an egg.

The owner manual recommends 91 octane and higher. Why not use what Acura recommends? The 30 cent difference, as someone pointed out, between regular and premium does not save that much money to make a difference or to risk knocking with the engine.

People think they are smarter than the car companies who built the car and researched what works best, but they aren't. Its simple, if you wanted to use regular, you should of bought a Honda.