mojque

I know there's already a fuel economy post on the board, but given the redesign, I think it's relevant to start another thread.

I recently watched the youtube video at the end my post, and I am particularly interested in comparing MPG between regular and premium. I've seen the "reduced performance" warning thrown around, but never any concrete numbers. Based on his results, I calculated these figures:

--First leg with regular: 331 miles using 13.6 gallons, 24.34 MPG
--Second leg with premium: 381 miles using 14.1 gallons, 27.02 MPG

I'm not sure if those numbers will hold up in the long run, but if they do, it's a substantial difference that justifies the extra cost premium.

Reasoning: If you drove 15,000 miles/year and averaged 24.34 MPG with regular gas at $4/gal, you'd use 616.31 gallons for a total cost of $2,465.25. Driving the same 15,000 miles but averaging 27.02 MPG with premium gas at $4.30/gal, you'd use 555.12 gallons with a cost of $2,387.01. That's a cost difference of $78.25 (3.28%) in favor of using premium gas.

As the price rises, that savings percentage increases because the premium cost is a static value. For example, if regular costs $5/gal and premium were $5.30/gal, the difference increases to 4.74%. I'd throw in an example of the price going down, but who sees that happening?

For those few who do have 2013's at the moment, what are your experiences with fuel economy when using different octanes?

https://www.youtube.com/watch?v=gfU70HX0D-s

HokieAcura

I can't comment on the 2013 RDX as we currently own at 2010 TSX but am considering the move to an MDX or RDX in a few years. I was really hoping the RDX would be regular fuel only, not the "premium recommened" tag. I've never experimented in our TSX but from some other posts it seems any savings from using regular is offset by better performance and fuel economy from premium.

It was interesting to note he claimed the RDX came prefilled by the dealer with Regular fuel? I thought this was strange in that Acura recommends premium, it's hard to believe the dealer would be that cheap and choose to fill the tank with regular.

Rocketsfan

If the car is allowed to use regular, then I wouldn't expect the dealer to put premium in. If Acura recommends "premium only" and they put in regular, I'd be pissed.

weather

I am not sure what the difference between Premium and Regular unleaded but here in Canada (where we pay always alot more), the difference is on average 5 cents per litre (at Costco).

So on a 60 litres tank (if fully empty) --- > 3.00$
If I fill up 4 times a month ---- > 12.00$

It is one thing to be worried about rising cost of fuel but the spread between regular and premium will always be about the same.

If people are concerned about an extra $12-20 a month between regular and premium fuel, Acura's are not the vehicle they should be shopping for. Not trying to be rude but rather, put things in perspective.

buzzdsm

Another plus for me using premium is that it doesn't contain ethanol. On the other hand I pay about 20 cents more per gallon.

weather

I agree....I am not a big fan of putting ethanol in my vehicle either so the premium by-passes it.

You are in the same situation as me.....60 litres = 15 US gallon.

Therefore, 20 cents/gallon X 15 Gallon = 3.00$ extra per tank.

So if you fill up about once a week, that is an extra 12$ a month. I am happy to see that your numbers confirm mine as well. For me, the big deal with cost of energy is not between premium vs non premium but rather, overall fuel economy. If I want to save money at the pump, I look at the vehicle I drive rather than the type of fuel it takes because the spread between premium and regular will always be the same....

Doug W.

I had to come to a similar conclusion for my TL and the preceding '01 Maxima that both require premium. For me it came down to the logic that if I am spending this kind of change on a car I chose to buy why would I skimp on fuel when the actual cost differential is not overwhelming. Otherwise I'd go back to Honda (that I also like) or something else that was not designed for premium. My wife and I recently ordered her new RDX and I am not certain what fuel we'll decide to run, but doubt we will put 87 octane in it regularly. For the heck of it, I will try to discern if there would be any meaningful performance trade-off running on the mid-grade 89 octane. Otherwise we'll run on 91.

Michael Fetty

just picked up rdx saturday night. drove 130 miles all highway. Premium Gas @ 65mph was 32mpg. 72mph was 31mpg. 75-77 was 29mpg. So this is an odd range but still a lot better than the 2007 that we got rid of. Love the new ride.

rdxm

I fueled my 2013 RDX for the first time today. The on board computer displayed 10.3L/100 and the calculated fuel consumption was 10.8L/100.
I did a mix of 40% suburban driving and 60% highway.
The gas was whatever the dealer put in, they told me it was premium.

pickler

quite a few rdx shots on the internet showing average of 21 mpg. not much difference. as for regular/premium regular is fine if your not racing it. at 5000rpm engine might enrich A/F ratio and retard timing to prevent knocks. this might result in ~5hp loss at 6000rpm. otherwise it has no negative impacts. This is the exact same engine from the accord.

Michael Fetty

just finished a full tank of premium, 390 miles, 90% highway. trip showed 29.1 mpg

just started a new tank of regular gas 87 octane and am getting 25.1 mpg at 50 miles so far 90% highway.

so it does make a difference but seems like the cost of fuel right now isn't justifying the cost.

richardyc

sure it does, did you actually work out the math? you are roughtly paying about the price of 1gal of premium to get extra 64miles.

mrgold35

390 miles / 29.1 mpg = 13.40 Gal of 91 X $3.84 NM $ per gal = $51.46 of gas used
390 miles / 25.1 mpg = 15.53 Gal of 87 X $3.64 NM $ per gal = $56.55 of gas used

If you still hold at 25.1 mpg using 87 octane for the rest of the tank, it doesn't look good in the long run going with the cheaper gas. You have to average about 27.6 mpg using 87 Octane just to equal the $$ you spend just using 91 octane at 29.1 mpg.

mav238

I assume those mpgs are mainly hwy driving.

Honestly i enjoy the turbo a lot more than a V6. Will consider a hybrid instead of a V6 when it is time to change the RDX.

Sly Raskal

iTrader: (1)

Moved thread to the new 2nd gen RDX forum.