You don't check the tire pressure on rentals?

 

Certain driving techniques (lighter acceleration, slower overall speeds, etc) will improve the performance of both hybrids and traditional vehicles, but I'd be willing to bet they have a more pronounced effect on hybrids (due to lower coefficient of drag, etc). But to answer the question of how much of an effect does the hybrid have, I finally had a chance to look them up the EPA ratings I mentioned earlier:

Engine - EPA rating
4 cylinder - 21 city/31 highway
6 cylinder - 19 city/28 highway
Hybrid - 33 city/34 highway

Assuming these numbers are based on the same testing profile, the hybrid gives 57% better fuel mileage in the city than the 4 cylinder, and 74% better than the 6 cylinder.

The highway performance is not as much of an improvement, 10% over the 4 cylinder and 21% over the 6 cylinder.

 

Actually, I sometimes do if I intend to keep them for more than three days or so and have any distance to go (if the tires look OK). If an air supply is handy, I set them at 38 psi in those cases and back to 32 again before turn-in. Another thing, not all of them have OEM tires, and not all of them are LRR.

 

EPA highway mileage ratings do not capture what a hybrid is capable of. I'm no sure of the reason since I have not studied their protocall. My guess is that their test is not long enough. When I drive the freeway, I note a significant improvement in mileage after driving for 15 minutes so if you drive on a trip or longer than 15 minutes on the freeway, you can expect to exceed the EPA numbers with some qualifiers. High winds, cold temperatures and large hills can reduce the numbers.

On relatively flat terrain in Southern California, I can get >50 mpg after driving minutes. There is no way a non-hybrid camry would do this unless driven at a very low non-highway speed. Incidentally, I drive 60-65 mph.

 

I agree. I'm exceeding the EPA rating of my car, as are many others here.

I'm just trying to address the OP's original question about a hybrid advantage in the same vehicle. I take that to mean no changes in driving habits, which should be the EPA's test protocol since they have to test each engine the same way to make the ratings consistent.

It definitely underestimates the actual capability if you take advantage of all the maximization strategies that are out there, many of which work better on a hybrid than on a traditional car.

 

The unfortunate thing is that too many people rely on the EPA numbers in making a car buying decision. A friend of mine cannot comprehend that you can exceed their rating by a significant amount. The percentage is much greater than for a non-hybrid.

 

Personally I don't implement any drastic strategies in my driving and am getting better than the EPA numbers. The only things I have done is slowed down to the speed limit +\- 5mph and learned how to utilize the hybrid system. I also pay a fair amount of attention to the terrain now to so as to maximize the downslopes and minimize the upslopes. I haven't spent enough time to try and figure out P&G or any other techniques.

 

2006 Civic Coupe EX. Yes, it's a manual.

 

I've found that what you're doing is extremely drastic when it comes to fuel economy. I pretty much do this exact thing while driving my normal Civic and see a 11-13 MPG improvement from before. Amazing that by simply slowing down and being cautious of how much I press down on the gas pedal I increased fuel economy by 25%. Now imagine the amount of fuel that would be saved each year if everybody wasn't in a hurry to get to 75+ and instead drove "normally".

 

Exactly.

Oh yea I forgot I pumped my tires up to about 40 - 42 psi and noticed a difference. FYI the max sidewall psi is stated 51 psi for the OEM Bridgstones. Being in the tire industry somewhat I am told that 51 is safe to fill up at a cold level and yes as the tire heats up the pressure will increase but this is allotted for by the manufacturer.