I tried the 2500rpm rule today on a 100 mile trip (200 miles total round trip) and found that in my case, this theory is supported. Although I drifted a couple of times to maybe 2600 or reaching 2700rpm, it was brief in duration.

I usually average about 27.5/28.5 combined as per the DIC. I keep a record of my fuel fill-ups and rough math told me it was close. Today I averaged 30.5 by limiting my rpm in this manner. Average speed was about 68-69 on the hwy, but the DIC averaged 47 due to a good amount of local driving once I got off of the interstate.

This is with the 2.0L, manual trans and the GM Turbo Upgrade kit.

 

Keeping your RPMs down is a good way to maximize fuel mileage, but you can really boost your mileage if you combine limiting hard acceleration with limiting the RPMs as well as limiting your use of the brakes! Remember breaking is taking the momentum (kinetic energy) and turning it to heat. As stated, 30% of you're fuel is used just to get you moving, the less you brake, the less you need to get restarted. To Accomplish this, LOOK AHEAD AND PLAN. If you see a light a 1/4 mile up the road turning yellow, get off the gas and coast. I can't tell you how many people that I ride with that complain about fuel mileage and only know 2 mode of driving. Hard accelerating and hard braking.....
Try to look ahead and plan accordingly

 

I completely agree esmarkey. And the more you plan ahead while you drive, the less braking you have to do, prolonging the life of your brakes as well. I regularly get 7-7.7 liters/100km on my 440km daily drive, sometimes can get 5-6 l/100km while on a flat straight stretch too.

 

The problem I have with the 2.2L HHR is the fact I had a 1991 Honda Civic LX with a 1.5L engine that got about 30-32 MPG , and I understand that I now have a 2.2L engine and a heavier vehicle weight overall plus the fact that that the engine has almost 110,000 miles on it.The fact is,it is newer technology and a great engine as far as performance,but the mileage is terrible,you think it would be alot better. Today I changed the plugs when I did the oil change and I used the AC Delco Irridium plugs , so we'll see if I get any better mileage.I will say the old plugs were ready to be changed as they were gapping anywhere from .045 to .050. Hopefully , the newer plugs will make a difference.I could tell a difference in the accelleration through part-throttle and take-off.

 

I know ill probably hear crap about this one but I dont think the newer cars get all that better gas mileage than older cars. Sure some are the exception but over all I dont think so. I use to own a 86 ford bronco II that could get 20+ mpg and my dad is still driving an 90s grand am that gets better mileage than my HHR. They say we are getting better mpg but I dont buy it, I only got the car for its looks.

 

I never let my RPMs go past 3k...just never have in the HHR, basically to help fuel economy. I just thought of it on my own, didn't read it (or maybe subliminally!) Either way, with my very easy driving (slow take offs, coasting, no lead foot), I really think I should be getting better...but it's hard to say what my average is since my driving changed...now I go to school more, which is more highway driving, and it seems to be getting better. This last tank I averaged at 29, the one before that when it wasn't as much highway I got 26. That isn't city driving, it's mostly 55mph in the country.

 

Jeffro... not only was your 91 Honda much smaller and lighter than your HHR... it also had far less stringent emissions controls on it. What kills the power and fuel economy in modern engines is all the emissions equipment.

 

What he said ^

And I wonder which one had more wind resistance....
That's like me saying my HHR is defiantly better because it gets better mileage than my Silverado pickup truck.... Apples and oranges.

 

I am currently averaging 26MPG on my daily commute... running premium. Just if anyone wanted to know.

 

Last week I had to do a 300 mile round trip one day, I got 34.2 highway. Cruise set at 75 the whole way. That was using a calculator.