Accord Newbie; 27.8 to 36.2 mods
 

Just found this site: I've got lots of reading to do! I'll start by posting my results - please ask any questions / criticize, whatever.

This is what I have – directly from my modification diary for the car. Most of the gas was from the same station; the same pump. Always filled the tank to the pump’s automatic cut-off. All of the driving was mixed, the same commute, about 65% Interstate.


(first recorded; tires are ~ten years old)
15AUG11 345 miles@ 12.927 gallons = 26.7 mpg
1SEP11 358 miles @ 13.791 gallons = 26 mpg

(first tank on new LRR tires at 50 psi)
21AUG11 397 miles @ 14.264 gallons = 27.8 mpg
26AUG11 396 miles @ 13.6 gallons = 29.2 mpg

(-mirrors, antenna, mudflaps; + wheel discs)
9SEP11 406 miles @ 13.748 gallons = 29.5 mpg
16SEP11 446 miles @ 14.545 gallons = 30.7 mpg
23SEP11 435 miles @ 14.71 gallons = 29.6 mpg
2OCT11 421 miles @ 13.871 gallons = 30.6 mpg

(lowered ~2-1/2")
11OCT11 474 miles @14.42 gallons = 32.9 mpg
24OCT11 470 miles @ 14.753 gallons = 31.9 mpg
31OCT11 483 miles @ 14.72 gallons = 32.8 mpg

(full skirts, 0° toe-in)
7NOV11 476 miles @ 13.50 gallons = 35.25 mpg
14NOV11 468 miles @ 13.991 gallons = 33.5 mpg
22NOV11 486 miles @ 14.47 gallons = 33.6 mpg
29NOV11 502 miles @ 14.692 gallons = 34.2 mpg
8DEC11 510 miles @ 14.83 gallons = 34.4 mpg
14DEC11 488 miles @ 14.47 gallons = 33.7 mpg
10JAN12 496 miles @ 15.0 gallons = 33.0 mpg
19JAN12 477 miles @ 14.581 gallons = 32.7 mpg
26JAN12 466 miles @ 14.4 gallons = 32.4 mpg
16FEB12 453 miles @ 13.677 gallons = 33.1 mpg
5MAR12 486 miles @ 14.7 gallons = 33.2 mpg
22MAR12 466 miles @ 13.7 gallons = 34.0 mpg
4APR12 500 miles @ 14.7 gallons = 34.0 mpg
13APR12 508 miles @ 14.67 gallons = 34.6 mpg
22APR12 508 miles @ 14.22 gallons = 35.7 mpg
28APR12 485 miles @ 13.9 gallons = 34.9 mpg
22MAY12 480 miles @ 14.1 gallons = 34.0 mpg
7SEP12 501 miles @ 14.575 gallons = 34.4 mpg

(GasPods added)
14SEP12 513.5 miles @ 14.262 gallons = 36.0 mpg
21SEP12 499 miles @ 14.329 gallons = 34.8 mpg
1OCT12 506 miles @ 13.975 gallons = 36.2 mpg

Mods look good.

A heads up: you're going to take some flak (abundant skepticism) for the gas pods though. Don't take it personally!

Welcome to the forum!

Did you make those wheel discs?

Thanks.

Thought I might take some flak for the gaspods!

Interestingly, adding them gave me two new vibrations at 70 mph - one in the dash, and one somewhere in the rear package tray area - so they are doing something with the airflow.

Another thing, and I don't have a way to quantify it, is that the rear vertical surface of the car doesn't SEEM to get as instantly dirty as it did once I put the skirts around.

Again, not a real result - just an observation.

Should have the fourth tank through this weekend and another mpg result.

Forrest

Since the benefit of turbulators/VG's on the trailing edge of a vehicle isn't generally accepted, only an A-B-A test will satisfy most members here about their impact. (On the other hand, most people wouldn't be as skeptical about an air dam for example, since they're an established & well understood modification.)

It's great that your tank-to-tank numbers increased but there are too many variables in that type of comparison to be convincing.

Just FYI, this thread describes "ideal" testing: http://ecomodder.com/forum/showthrea...ery-11445.html

What about those wheel discs - are they commercial ones painted to match, or did you DIY them from scratch?

I might pull the GasPods back off after ~two thousand miles just to see, if it would be of any interest - I guess everyone's read the Mitsubishi White Paper on the subject.

I do try to be as consistant driving as I can; always cruise control set at 69; exact same commute each week; traffic is light and never varies. Same two gas stations; same two pumps.

I am a professional ME - I had gotten the car to do an electric conversion, but the battery equation never made sense - the payback was too long, with $26K in LiFeMnPO4 batteries alone for a 115-mile range.

The discs are aluminum lenticular Moon discs; trimmed ~1/4" to fit inside the lip of the Honda alloys; screwed on with SS 10-32s, IIRC. Paint is Sherwin-Williams enamel; color matched to the car, and rolled-on as shown on innunerable web links - I painted my "little" car white that way!

The mirror-delete plates are painted the same way.

Forrest

Thanks for that wheel disc info. I thought they looked like you started with commercial discs. Either that or you have serious fabrication chops & I wanted your secret!

Yup. Roof-mounted VG's - we've seen a couple of OEM's do those (Renault being the other on an "ecomodded" non-production car). The key difference being: we've never seen an OEM do trunk-mounted ones.

Have you got a partial grille block? Another well understood & relatively easy mod.

Any further mods planned?

Thanks for that wheel disc info. I thought they looked like you started with commercial discs. Either that or you have serious fabrication chops & I wanted your secret!

The silver/alloy surround "ring" of the OEM wheel looks sharp too.

Yup. Roof-mounted VG's - we've seen a couple of OEM's do those (Renault being the other on an "ecomodded" non-production car). Never seen an OEM do trunk-mounted ones though.

Have you got a partial grille block? Another well understood & relatively easy mod.

Any further mods planned?

Other variables change as the months go by, though: your tires' RR is decreasing as they age & wear; ambient temperature affects MPG a lot as the seasons change (A/C use? Warm-up times increase as summer temps recede; numerous other impacts on RR & aero drag); fuel formulations changes around this time of year to the slightly less energy dense "winter gas"; etc.

Time passing is problematic for evaluating small modifications!

Yeah, that's downright impressive to see an MPG increase in the winter. I'd love to see what you're nailing down in the cool but not cold months of spring.

Chris