Is this true? (Instantaneous MPG higher at 60-65 versus 50-55 using DWL)

[SilverCrown9701]

Originally Posted by MetroMPG

It's really unlikely.

Watching the "instant" MPG gauge is problematic. It moves around too much to be very useful in predicting overall MPG, and we tend to cherry-pick observations that lead to confirmation bias.

If you look at our collection of speed vs. MPG graphs, the dominant pattern for normal venicles is: best cruising MPG typically happens at the lowest speed in top gear.

http://ecomodder.com/forum/showthrea...you-15182.html

2002 Camry automatic:

I wish that someone had a map like this for a 2001 Toyota Camry. This chart here is for the next generation of Camry, with a completely different engine, chassis and transmission. A 2.4L with VVT and timing chain. Mine is the 2.2L engine.

I can't even find a BSFC for this car

[SilverCrown9701]

What I do know is that driving using DWL, no A/C and using my UltraGauge have helped me achieve my 37 MPG average from my last fillup. I will continue testing.

[SilverCrown9701]

Originally Posted by 101Volts

That's what I've been wondering about my Dad's 3-Litre Caravan. However, I don't have a lot of flat areas nearby that I know about to test this on being in Pennsylvania. I noticed that with the TPS being at 19, 20 or 21 and going at about 70 MPH on a Highway (There are some places where the speed limit is that high in PA) the Instant MPGs actually go in the upper 30s and lower 40s according to the ScanGauge II (Set at -5% or -4%)

That's with tires at 45 PSI, no roof-rack and with the middle and rear seats out.

That sounds similiar to my situation but I think we should both continue testing this to confirm it that's a great achievement by the way!

[MetroMPG]

I realize it's not the same car. But I doubt there's anything special about your Camry that makes it not follow the pattern of all other cars:

Lowest practical speed in top gear = best fuel economy.

The exception may be in hills: a higher average speed may help if it permits you to stay in top gear on ascents while bleeding speed (DWL) while avoiding downshifts.

You're doing a good job of investigating. Keep it up!

[basjoos]

Originally Posted by SilverCrown9701

I wish that someone had a map like this for a 2001 Toyota Camry. This chart here is for the next generation of Camry, with a completely different engine, chassis and transmission. A 2.4L with VVT and timing chain. Mine is the 2.2L engine.
(

There's nothing stopping you from making one of these maps for your car. All you need is a flat 4 to 8 mile stretch of lightly-trafficked highway and a few hours of time on a non-windy day to make the constant speed runs in both directions at each speed you want to graph.

[SilverCrown9701]

Originally Posted by MetroMPG

I realize it's not the same car. But I doubt there's anything special about your Camry that makes it not follow the pattern of all other cars:

Lowest practical speed in top gear = best fuel economy.

The exception may be in hills: a higher average speed may help if it permits you to stay in top gear on ascents while bleeding speed (DWL).

You're doing a good job of investigating. Keep it up!

Thank you!

I don't want to give myself a false sense of hope. I feel really good when I see those numbers in the 40s and 50s. It makes me feel like I'm accomplishing something worthwhile.

Now whether these numbers will increase my average MPG, only time will tell.

[SilverCrown9701]

I'm having a difficult time getting near my last tank average of 37 MPG. So far, my UltraGauge shows that I'm only averaging 32.6 MPG.

The thing that is annoying me is that I have to keep my throttle position/engine load at a certain range to prevent my car from slowing down on flat to slightly elevated terrain and thus slipping out of overdrive. I have to keep it over 17 TPS and 55 % engine load unless I'm going on a downgrade. Due to these higher numbers, my instantaneous MPG is showing upper 20s to low 30s.


What am I doing wrong here? I'm using DWL with no A/C just as last time except I'm not using any cruise control on this tank.

[SilverCrown9701]

Also...

I notice by observing my UltraGauge while operating cruise control that during downgrades as the cruise control is slowing my car down to maintain speed, my Instantaneous and Average MPG will increase by several tenths to up to a few points during any trip, as if it appears to be increasing my mileage. Is this a GLITCH or is it actually improving my fuel economy??

[2000mc]

So, you say your car seems to get better mileage when going downhill?

[gone-ot]

...that's *WHY* I prefer to continuously collect data (via computer) so that it can be subsequently filtered and analyzed to account for "out-lier" data points (single item) and periods/trends (climbing hill; coasting downhill; etc.).