Last post on Aug 28, 2013 at 6:17 AM
You are in the Acura RDX
What is this discussion about?
Acura RDX, Fuel Efficiency (MPG), SUV
#184 of 223 Re: 15.9 mpg on my new RDX 1st tank [woodyww]
Apr 01, 2009 (4:43 pm)
Putting a smallish 4 cyl. in the RDX isn't so much the problem as is the fact that it is turbocharged. A normally aspirated engine would have a compression ratio of 10:1, 12:1 with DFI in the CX-7. In order to "accomodate" the dynamic increase in CR with turbo boost the base engine CR must be derated from the norm.
Since most of the time you spend driving the RDX you are off-boost you are sacrificing a serious level of FE improvement for the rare and brief periods of "on-boost" acceleration.
Mill the engine head to raise the CR to the "standard" of 10:1 and "wire" the turbo wastegate fully open and you will likely see an FE improvement in the range of 30-50%
Or even better use VVT-i to dynamically change the CR from Atkinson cycle mode for cruising but into the Miller cycle as boost rises.
So much for TURBOCHARGING...!!
#185 of 223 so to save gas you should accelerate as fast as you can to 60mph?
Apr 07, 2009 (6:15 pm)
then coast from there?
The traditional ease the pedal acceleration won't save gas?
#186 of 223 1st tank of gas = 22.1 miles/gallon
Apr 19, 2009 (3:24 pm)
I've finished my first tank of mystery gas (dealer supplied). Some city driving (steep SF hills), lots of highway miles, and I went up and down the Santa Cruz mountains five times.
330.7 miles/14.966 gallons = 22.1 miles/gallon
Love the boost when you need to merge and pass. The handling is phenomenal on the twisty mountain climbs and descents! I admit that I went pretty easy on the gas pedal as the engine is still breaking in, but I still has numerous full-on accelerations to merge and pass on the freeways. Gas mileage was probably improved as descending from the mountains was most engine braking and little to no throttle.
The only negative so far is that the navi got lost in the heavy tree cover of the SF mountains.
#187 of 223 Re: 1st tank of gas = 22.1 miles/gallon [mark4490]
Apr 26, 2009 (8:06 am)
I got back from a trip north to the coast. From the South Bay, N101 to Fortuna and back along the Pacific Coast Hwy (CA-1).
720 miles/35.196 gallons = ~20.5mpg
Not bad considering we were rolling through high elevations so the boost was kicking in even while descending.
The drive down CA-1 was a BLAST! I finally got to really test the SH-AWD. I'm not sure, but I think the VSC kicked in on one corner that I overcooked. It was both downright terrifying and thrilling at the same time. There was no way I was going to take my eyes off the road and glance down to check how many bars I was up to, but on one sweeping corner I saw the meter go up to 3 bars.
We also had a huge scare and almost ran out of gas on N101. The low fuel indicator had gone off, but I thought I could go another 50 miles before it got serious and we'd have to look for a gas station. The low fuel light had gone off on me before. That time I went 40 miles and found out that I still had 4+ gallons left in the tank when I filled up. Luckily, my GF is from the area so she knew that there was a 24 hr gas station near Garberville. When we filled up I was surprised that we put in 17.3 gallons! I thought we'd have ~3 gallons left! I'm not sure if we would have made it to Garberville. We'll fill up when it gets down to 1/4 tank next time.
This brings up an issue I have with the navi system. Little towns with little to no services show up (Leggett, Piercy), but bigger towns with (ie., Cloverdale) don't unless you zoom all the way in. I don't think that gas station showed up on the RDX navi system, either. My Garmin handheld GPS is much better and more reliable. If I didn't have a "local" with me I could have been in serious trouble.
#188 of 223 Re: 1st tank of gas = 22.1 miles/gallon [mark4490]
Nov 08, 2009 (6:51 am)
I'm wondering why everyone gets such poor mileage? On my 2010 RDX I'm on my second tank of gas. I'm getting 22-23 mpg driving around the northern suburbs of Chicago. This includes about 40% highway at which I drive 70-80 mph. I don't gun it from a stoplight. I find that it still moves out ahead of the cars around me without having the turbo kicking in. It has awesome power when you ask for it. I'm as happy as can b with my RDX!
#189 of 223 Re: 1st tank of gas = 22.1 miles/gallon [geohov]
Nov 08, 2009 (3:44 pm)
Most of the time the RDX runs in detuned/"derated" mode. During "cruise" mode the compression ratio is significantly reduced from the Otto mode standard.
#190 of 223 2010 RDX SH-AWD good mileage
Dec 14, 2009 (11:31 am)
I'm getting slighly better than EPA.
I am "breaking" her in, about 500 miles, and drive 10% city, 90% highway, averaging about 22.5-23.5 on the trip computer.
Average speed is 69 mph acc to computer.
I floor it here and there, but largely feather, stay out of boost, and my range is close to 350 miles to a tank so far. . .I should hit 400. . .will keep everyone posted. . .the new DFI def should improve mileage. . .
Remember EPA revised all mileage estimates in 2009 because of the "cash for clunker" program, so estimates are off in FAVOR of more mpg apparently now. . .
#191 of 223 Re: 2010 RDX SH-AWD good mileage [shivaswrath]
Dec 16, 2009 (8:21 am)
So far with about an average speed of 50 mph, I'm getting anywhere between 21-22mpg with my SNOW tires on, Bridgestone DM-V1's (235/55/18's). . .
oddly enough, I'm getting the same mileage as my 2005 Evolution VIII which was 800lbs lighter. . .go figure, technology. . .
Jul 22, 2010 (6:27 am)
2nd tank of gas, not dealer gas at time of pickup got me 22.4 with city driving but we live on the ouskirts, most driving is city highways, not a ton of stop and go. Normal to light driving. Pretty happy with that MPG. Secondly, for the MPG nerds, I found a great iphone app "gas cubby" it is free if you can handle the pop ups, very nice app