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I’ve just started hypermiling, and so far I love it! I’ve got a 2006 Acura RSX Type-S, nice little car that I thought would be able to get good gas mileage. I’ve been keeping gas mileage logs for the last two cars I’ve had. (Nifty excel sheet here: http://jjhack.dyndns.org:8069/Mileage.xls ) EPA shows a 24/31 rating for the car, and with normal driving I see low 20’s in the city, and about 30 on the interstate.

I just placed an order for a ScanGauge-II (group buy :) ), so I can’t wait to be able to see real-time numbers on mileage.

I’ve been coasting out of gear a lot, and starting to get into FAS coasting. I love having a manual transmission, so I can bump start it. DWB has been fun as well, especially on the corners, it’s sooo much fun to have a car that handles well.

Pulse and glide is a bit harder for me to get the hang of. I don’t think my pulse is hard enough, like I’m spending too much time accelerating. Which I’m sure is at a low mpg. And then my coast does not seem to be very good unless going downhill. I might need to check my tire pressures.

I’ll keep plugging away at it. I can tell right now the tank I’m on is going to be good. ~210 miles on the tank, and just below 3/4 on the gauge. Normally I’m below 1/2 tank at the mileage.

Yes I usually have to push the pedal somewhere between 1/4th and 1/2th of the way down. This overcomes pumping losses and opens the throttle plate completly up. I have a vacuum gauge, so I just watch for the psi to hit 0 instead of -20 that it cruises at.

I was initially barely touching the throttle, and it would take like 20 or 30 seconds for me to reach my peak on the pulse. Now its about 8-12 seconds on the pulse, and 16-30 seconds on the glide, on nearly flat stretches of road.

The scan gauge seems to really help a lot of people, several people have said that they easily made their money back on it, so you should be in good shape once you get a hold of it.

Thanks for the tips. My pulse is about 25-30 sec, very light acceleration. I guess it just seems counterintuitive to hypermiling to accelerate hard (well harder than you have to), but I understand that is needed for a good P&G.

This makes it more clear:
http://www.autospeed.com/cms/A_110216/article.html

Thanks for the link, i'm going to have to bookmark that.

This makes it more clear:
http://www.autospeed.com/cms/A_110216/article.html

Wouldn't that indicate that a faster acceleration off of a stop is going to be more efficient? Should I be cruising around at 7000-8000rpm in the S2000 to get that sweet spot? It seems counter-intuitive. I understand that the engine may be more efficient in creating power closer to it's torque peak, but it is really going to use less gas getting up there?

PaleMelanesian, that was a great link. Very insightful, it's good to get in there and look at the numbers and to see what I'm thinking about in regards to light acceleration loads.

Wouldn't that indicate that a faster acceleration off of a stop is going to be more efficient? Should I be cruising around at 7000-8000rpm in the S2000 to get that sweet spot? It seems counter-intuitive. I understand that the engine may be more efficient in creating power closer to it's torque peak, but it is really going to use less gas getting up there?
Yes, but only to a point. You don't want to be anywhere near 7000 rpm, ever! What you want is low rpm and high throttle, giving you merely moderate acceleration.

From all those charts, the sweet spots are: 2500rpm, 3000, 3000, 2000, 2500
The insight is abnormal, with 2 peaks at 1750/4000.
The last chart is a rotary. Completely different animal.

Adam, you have a motor very similar to mine, and I was thinking the same thing. But I think the friction of the motor gets so high at the high RPM’s that it’s counterproductive. I think our motors are a little different in that the peak torque and hp is right around redline, which itself is a very high 8000+ RPM’s. I just can’t see how riding in VTEC (6K+ RPM’s) would be efficient. I’m going to have fun trying different throttle positions and engine loads with the Scangauge.

Also when starting from a dead stop you have to overcome some significant frictions, so one would think harder acceleration to get to you peak torque quickly would be best, but in real world driving I’m pretty sure that is not the case. I’m just not sure on the physics behind it.

Wouldn't that indicate that a faster acceleration off of a stop is going to be more efficient? Should I be cruising around at 7000-8000rpm in the S2000 to get that sweet spot? It seems counter-intuitive. I understand that the engine may be more efficient in creating power closer to it's torque peak, but it is really going to use less gas getting up there?

Yes, but only to a point. You don't want to be anywhere near 7000 rpm, ever! What you want is low rpm and high throttle, giving you merely moderate acceleration.

From all those charts, the sweet spots are: 2500rpm, 3000, 3000, 2000, 2500
The insight is abnormal, with 2 peaks at 1750/4000.
The last chart is a rotary. Completely different animal.

I think my hp and torque peaks are a little higher than normal ;) . I redline at 9,000rpm, VTEC changeover is at 6,000.
240 HP @ 8,300 rpm; 153 ft lb @ 7,500 rpm

But yeah, I understand the full throttle shorter shifting idea a little more now. You just want to open the throttle plate enough to avoid the pumping losses, not necessarily rev the engine to the moon. I would have two sweet spots like the Insight too btw.

I guess I would have two as well. It would be interesting to run some numbers to find out where they exactly would be.

I would have two sweet spots like the Insight too btw.

One thing I am worried about is raising my tire pressures. I believe this sacrifices handling, and that is not really something I would like to give up. I live for the corners! :D

Try it. At least try the sidewall-stamped pressure. Try your favorite corners before and after. You might be surprised. ;)

Try it. At least try the sidewall-stamped pressure. Try your favorite corners before and after. You might be surprised. ;)

Absolutely. I’ll post how it goes.

I'll just add that most of the time at Autocross events people find that they need to add more psi rather than take it out for increased performance because they find themselves rolling over onto their sidewalls during extreme cornering.

So in other words, do it. I just checked the psi on my S2000's tires and they're at 35psi when the max is 44psi. Granted they're 140 treadware rated, so even at 44psi they'd be plenty sticky. I bumped the Accord's tires up to 44 for my trip last weekend though.

I set my tires to 40psi last night (they were at 32psi), and took the curvy road to work this morning. The extra pressure did not adversely affect the handling. But I think the ride is a little rougher, not much though. I notice that coasting is significantly better, so it should help my FE/P&G efforts.

The max sidewall for my tires is 44psi. I might leave it at 40 for a couple of days, and then try 44/45psi.

Can’t wait for my SG-II to get here, then I’ll be able to see the effects. Thanks everyone for all your help!

Almost all real street tires will grip better at higher pressures than the ones listed in the car's owner's manual. AutoXing has taught me (and many of my friends) that.

Your engine may make the best power per fuel burned at high RPM, but the key is that you want to be burning the least fuel for the power you need at any given moment! It's not quite the same thing. Remember, at 60 MPH your car takes about 10 HP to maintain speed, so when cruising at 60 MPH you want to have the engine where it makes 10 HP the most efficiently!

Acceleration is a little different, of course. You want something like 1/2 - 3/4 throttle, and relatively low revs. That might mean 3000-4000 RPM in your case; in my car (6800 red-line, power peak at 6500, don't remember torque peak) going 2000-2500 RPM seems to be pretty good.

The SG II will give you instantaneous feedback, which will be very useful to figure out those kinds of answers. I wish I could use one in my car...

-soD

Low revs are low revs, no matter the car or engine. I like to keep it below 2,200 rpm in mine. Since you have a higher-power engine, you should be at least as good at the same range. I would avoid 3,000 or higher at all costs. The only time I go that high is on the highway when I have no choice, due to gear ratios.

Yeah that is one issue with my car, the close ratio 6-speed. I’m just rowing through the gears if I shift less than 2k RPM’s, and I’m bogging the engine when engaging the next gear. I’ve been trying to shift right before 3k with very light throttle application, which keeps it from bogging. I’m sure I will have a bit more insight when the SG-II arrives.

"rowing through the gears" - very familiar. That sounds like what I have, only without the 6th gear on top. My 5th goes to 2,000 rpm by 43mph. I do use fairly high throttle, as mentioned above.

I received my SG-II yesterday, it is great device! (Thanks Wayne!) Now I’m trying to figure out when to DFCO coast, FAS coast, or ICE-On coast. I think the DFCO coast works best when you want to scrub a little speed off. The problem is there are a couple of small to medium hills on my daily commute. Not big enough for FAS unless I’m going over the PSL quite a bit. At normal speeds I can get DFCO to engage for a bit (8-10s) on the hills without loosing too much speed. I can go a bit longer (15-20s) with an ICE-On coast and see about 80-100mpg on the SG.

Just as a side note, according to SG I had a 30mpg trip to work today (little rainy out), it is about 15% HWY and rest city. I think I’m going to fill-up today, and I’ll get to see what my first full hypermilling tank pulls!

Now comes the art part of hypermiling. Learning all the fine points and which is better where. Good luck!

I just completed my first full tank of hypermiling. I got 30.23mpg, not bad with about 80-90% city driving. It’s much better than I have ever seen with that much city driving! In the past I would see 20-23mpg for city driving. My car’s combined EPA is 26mpg (old style), so I’m above the average! :)

Now that I have the SG-II I’m going to continue to tweak my technique. I want to see a 400+ mile tank out of my car, 13.2g tank so I would need to get 30.3mpg to see 400. I think 32/34 would be a good number to shoot for.

I love the current trip average mpg x-gauge. It’s neat to see what mpg I get each trip, and how the average moves with idling and coasting.

Another new member here. I've got a 2004 Acura RSX Type-S. I drive about 120 miles a day round trip to work. Last year I was getting about 29.8 MPG. This year, I had to put a new engine in the car and I'm getting 32.7 MPG. I guess the new engine had an updated chip in it. I just started running my tires at max sidewall, so we'll see how that does. I've got a Scan Gauge on order, so pretty soon I'll be hypermiling away like the rest of you.
:woot:

I got my scan gauge installed today. Time to check tire pressure and get ready for the weekly commute.

jfbrown42: It’s neat to see another RSX on here! I’ve been getting better at the different techniques. My last trip (http://www.cleanmpg.com/forums/showthread.php?t=13272) from Louisville to Bowling Green came in at 46.7 MPG! My mileage log is here: http://www.cleanmpg.com/index.php?page=garage&displayunits=MPG(US)&viewcar=1281

What motor did you get swapped, another K20A2, or did you step to a K20Z1 like in my model?

Let me know if you have any questions. I would love to see what results you achieve.

I got a replacement K20A2 (short block). The dealer put it in -- they aren't into modding at all. So far, I've just been distant drafting and NICE-on coasting (in neutral) down hills.

Is it hard for you to stay out of VTEC? Once a day or so I like to take it to the redline just to remind myself I have a performance car, then back to hypermiling I go. So far the max instant MPG I can get on my scangauge is 215MPG on a fast pulse and glide going downhill. That's fun!