Fuel Economy, Hypermiling, EcoModding News and Forum - EcoModder.com - View Single Post - The Amocat- 2005 Tacoma

aardvarcus · 11-13-2014, 07:32 AM

Wdb,

Good questions, I’ll address the MPG first. I have not done ABA, but I have been watching my fuel log intently to discern a FE difference. Unfortunately, my timing could not have been worse, as I installed the air dam right as the temperature dropped dramatically. Also my fuel log contains some tricky data, as most of the time I fill my truck with 87 Octane 90 Gasoline 10% Ethanol, but occasionally I get access to some 93 Octane 100% Gasoline, so many of the peaks on my FE graph are associated with that. Many of the dips on my FE graph are due to unusually large amounts of offroad driving.

Looking back through my fuel data, to avoid the 100% gas and offroad outliers, I will use six tanks from October 2nd through October 18th (next tank had 100% gas) as the baseline, and six tanks from November 5th (first tank with it installed) through 13th (today) as the test data. Note the temperature has dropped 20 degrees, from having morning lows in the 50s and 60s down to lows in the 30s and 40s. Also some of those tanks had V1.0 not V1.2 of the air dam.

In October, traveling 1812.928 miles using 70.015 gallons is 25.893 MPG. In November traveling 1114.568 miles using 42.633 gallons is 26.143 MPG. So the air dam is showing a roughly 1% increase which is within measurement noise, but given the 20 degree temperature drop, I don’t think the results are too shabby. So basically I like it, but let’s face it I am biased to it.

As for wind/road noise, there is a noticeable reduction in wind noise coming from air hitting the tires up front. The Tacoma’s had stock tire air deflectors which did ok when traveling straight, but the second I would cut my wheel very far, the noise would greatly increase. That has all but gone away. Note I am running 235/85R16 (32”) tires on stock wheels and have the front shocks raised up 1.75” so your results may vary.

For driving experience, the truck certainly feels more planted around turns, but that may just be my brain extrapolating a reduction in noise to better handling. According to popular literature, the truck should be experiencing reduced front axle lift, which is equivalent to increased downforce, and the handling isn’t all in my head. Anyway I feel better about taking the same turns at the same speeds.

In other news, I am refining my aero shell design, so that will get posted when I get something worth posting.

11-13-2014, 07:32 AM	#33 (permalink)
aardvarcus Master EcoModder Join Date: Apr 2012 Location: Evensville, TN Posts: 676 Deep Blue - '94 GMC Suburban K2500 SLE 90 day: 23.75 mpg (US) Griffin (T4R) - '99 Toyota 4Runner SR5 90 day: 25.43 mpg (US) Thanks: 237 Thanked 580 Times in 322 Posts	Wdb, Good questions, I’ll address the MPG first. I have not done ABA, but I have been watching my fuel log intently to discern a FE difference. Unfortunately, my timing could not have been worse, as I installed the air dam right as the temperature dropped dramatically. Also my fuel log contains some tricky data, as most of the time I fill my truck with 87 Octane 90 Gasoline 10% Ethanol, but occasionally I get access to some 93 Octane 100% Gasoline, so many of the peaks on my FE graph are associated with that. Many of the dips on my FE graph are due to unusually large amounts of offroad driving. Looking back through my fuel data, to avoid the 100% gas and offroad outliers, I will use six tanks from October 2nd through October 18th (next tank had 100% gas) as the baseline, and six tanks from November 5th (first tank with it installed) through 13th (today) as the test data. Note the temperature has dropped 20 degrees, from having morning lows in the 50s and 60s down to lows in the 30s and 40s. Also some of those tanks had V1.0 not V1.2 of the air dam. In October, traveling 1812.928 miles using 70.015 gallons is 25.893 MPG. In November traveling 1114.568 miles using 42.633 gallons is 26.143 MPG. So the air dam is showing a roughly 1% increase which is within measurement noise, but given the 20 degree temperature drop, I don’t think the results are too shabby. So basically I like it, but let’s face it I am biased to it. As for wind/road noise, there is a noticeable reduction in wind noise coming from air hitting the tires up front. The Tacoma’s had stock tire air deflectors which did ok when traveling straight, but the second I would cut my wheel very far, the noise would greatly increase. That has all but gone away. Note I am running 235/85R16 (32”) tires on stock wheels and have the front shocks raised up 1.75” so your results may vary. For driving experience, the truck certainly feels more planted around turns, but that may just be my brain extrapolating a reduction in noise to better handling. According to popular literature, the truck should be experiencing reduced front axle lift, which is equivalent to increased downforce, and the handling isn’t all in my head. Anyway I feel better about taking the same turns at the same speeds. In other news, I am refining my aero shell design, so that will get posted when I get something worth posting.