Phase I Complete: 18.8% Increase

[accord_minded]

Originally Posted by Old Mechanic

Avoid using DFCO if you can, coasting in neutral is much better at those high speeds. If you are going 60 and use .25 gal par hour idling, you are getting 240 MPG coasting. DFCO means you are using inertia to make that mileage infinite, but you will slow down much quicker than coasting.

If you are very familiar with the terrian, think of it as a roller coaster and where you can pulse and coast the longest or coast more total time. The tactic is dependent on the terrain. Coasting downhill with the engine idling is your goal. When the grades are very slight, pulsing uphill, not hard acceleration but very gradual (uphill) means you can coast downhill all the way to the bottom of the hill. If your downhill speed peak could get you a ticket then you want to reduce your top speed climbing the previous hill.

Think backwards from your top speed point. If your speed increases downhill then you want your peak speed to soon be gone coasting up the next hill and then when you get to the top of that next hill you don'y want to be going so fast that you overspeed on the next coast.

Like a roller coaster that climbs once then coasts through many hills curves and even loops, you want the ratio of pulses and glides to favor the glide, by as great a margin as possible. If you car is mechanically in good shape you should to easily beat highway EPA, but I think once you get to 40, you will hit the law of diminishing returns, however adjusting the "nut behind the wheel" will get you to 40% over EPA. Go 44 psi on your tires, and use the roller coaster strategy.

regards
Mech

Mech-- thanks for the sage advice. I was thinking DFCO vs. coasting in neutral was sort of a wash, but will try your advice. One reason I've been DFCO'ing is because before about a month ago I didn't know DFCO was even a thing. I'm still giddy when I see my scangauge read 0 GPH!

But the roller coaster analogy is easy to follow. In my case there are only 2 hills steep enough for the accord to maintain speed down the hill. So, I'm looking forward to some aero mods to extend my coasting range and then I'll have to judge my speed at the top better.

Cheers.

[basjoos]

As you aeromod your car, you'll find that the steepness of downhill required to maintain speed is reduced, so there will be more hills on your commute that you can maintain speed on when coasting down them. You'll also have to crest the steeper hills at a lower speed to avoid getting going too fast, overtaking other traffic, at the bottom.

[accord_minded]

Originally Posted by basjoos

...You'll also have to crest the steeper hills at a lower speed to avoid getting going too fast, overtaking other traffic, at the bottom.

I am really looking forward to the time when that happens! Thanks, basjoos.

[spacemanspif]

Good advice in this thread for everyone. To add my $0.02; nix the air dam idea and go straight for a full belly pan. It seems to be more beneficial than a dam AND you won't need side skirts either - it's advised to make tire spats and boat tails but not totally necessary. But considering your goals you should add the spats and tails to maximize you efforts. Look up arcosine's posts on his SC2 for ideas on pan, skirts and spats.

[accord_minded]

Originally Posted by spacemanspif

Good advice in this thread for everyone. To add my $0.02; nix the air dam idea and go straight for a full belly pan. It seems to be more beneficial than a dam AND you won't need side skirts either - it's advised to make tire spats and boat tails but not totally necessary. But considering your goals you should add the spats and tails to maximize you efforts. Look up arcosine's posts on his SC2 for ideas on pan, skirts and spats.

Spacemanspif:
Thanks for the advice and recomendation. Was not yet considering a belly pan because of technical difficulty (I don't even own jacks yet!) and reticence to put a lot of holes in the car. But my thinking is constantly evolving based on comments and advice. Looking at arcosine's stuff makes the belly pan look pretty easy, I must say. But first some low hanging fruit to get some successes under my belt. Then will tackle the belly pan.

[ECONORAM]

accord_minded, you could do something like I started with on my truck. No air dam, but I do have a short lip spoiler (splitter) protruding out level with my belly panels. The first step for that was making a piece that only extended back about 16 inches; I made some brackets that mounted to the bumper bolts and the splitter....