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Discussion Starter · #1 ·
Spent some time and made the V2 of the air dam today, Pics below of the process...

I had intended to get the upper part installed but ran into issues fabbing it and decided to sleep on it. So the bottom part is installed, first impression is it feels like there is more drag as the truck feels "heavy". So, gonna prove it to myself with some data logging. Easiest thing I can do is jump on the hiway for a 40ish mile out & back trip and average the data from the log. First trip would be with no air dam (4 bolts and its off), then the 1st version, then the 2nd version. I will use Torque to do the logging as its easiest to use, no laptop required like HPT needs (although, there is a stand alone setup to log without the laptop, just have not looked into it).

Google says its 38 miles out & back, will see if I can get this done today since its dry atm...

Anyways, there it is, still a work in progress....



















Trimmed





Installed
 

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Discussion Starter · #2 ·
Data... ~35 miles, Looks to me like the 1st version works the best...

.......................Load.....Rail...............Intake...Trip mpg........Boost
No Air Dam......24.232..16386.85........72.386..19.6653.........4.486
1st Air Dam.....20.865..14998.85........74.089..19.7181.........3.860
2nd Air Dam.....23.276..16174.74........71.385..19.8370.........4.405

All data cells were averaged except the Trip MPG column which was already averaged at the end of the log. Going to graph the first leg to the turn around point, that chunk of data I was able to hold 60 mph via cruise until turning around...


Adding 1st leg data... This data supports the 1st air dam as being the best... slightly better.

.......................Load......Rail...............Intake....MPG....... Boost
No Air Dam......22.888..16366.85........72.584.. 19.6502.........4.329
1st Air Dam.....22.116.. 16443.34........73.963....19.9018.........4.201
2nd Air Dam.....22.953..16603.74........71.438....19.5799.........4.390


So to clarify, I scanned thru the log file and averaged JUST the data that is @ 60 mph thru both ends. This eliminates the acceleration data from a stop at both the start and the turn around. This leg of the data was the best for all 3 tests, on the first run for the updated air dam I had to drop out of cruise for traffic. While it was a brief slow down, it is different than the other 2 tests.
 

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Discussion Starter · #3 ·
Thinking about the test from last night, I notice the IATs for the V1.0 air dam is slightly higher then V2.0. Next time weather is good enough to test, gonna look into IATs + load + boost for that same stretch with 3 different IATs. I know hotter is better, however its significantly hotter is better... I feel like I need to nail that data down and know without a doubt that the 18 mile stretch @60mph on CC is repeatable. So...

Next tests have to be a repeat of the 3 runs yesterday then the 3 IATs mentioned. Now I need some clear weather again... (high winds & stormy weather now...)

Also, not every swing can be a home run, but... never give up.
 

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Discussion Starter · #4 ·
test data RE: IATs from last night... These runs were with the front cover on full, half open and then removed. Also removed a plastic piece I have installed in front of the airbox that blocks cold air from getting to the airbox feed. This forces intake air to come from the engine compartment since I don't have a seal around the airbox to fender opening.

Load.........RP............IAT.....mpg....... boost
22.619......16583.......49.4...18.639....4.54.....no cover
23.115......16634.......58.8...18.914....4.39.....half cover
23.094......16630.......67.0...19.551....4.42.....full cover

The tune is the base tune provided by HPT during VIN lock, the data is collected using the Andriod app Torque via a Scantool.net MX Bluetooth scanner. No adjustments for mpg are set, as in vehicle weight, tank size etc... The MPG number shown is the last average value posted in the data being looked at. I have no idea how they are calculating their mpg #'s.

Anyways, I said I'd do this after the air dam repeat, it was too cold for me to want to be under the truck so I did this instead. Weather was breezy and dry, traffic was ok, had to restart the last test cause of traffic, could not hold 60 mph.

edit: and... no answer as to why load is lower with the colder temps, speculate timing correction

edit #2: I graphed the load values from 2 of the runs expecting them to be identical in shape and sure enough, they are. I can see the up hills, down hills and flats. It also occurred to me that this route might also be good for figuring out if timing is right under different load values during tuning. Meaning, start the test & tune with a logged base run, make an adjustment to the tunes cells @ the rpms logged. Get that dialed in then repeat at a higher speed (base, tune etc...), then a lower speed... once I have 3 data points, filling in the blanks is much easier.

I'm not angry with myself for not figuring this out sooner... just disappointed... :grin2:
 
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How well will this dam fare at higher speeds?
My engine is turning 1800 at 60 in 6th gear, and only 1700 at 69 in double overdrive.
If I run 65(1625rpm) the mpg drops about 2 tenths, versus 67mph(1675), and at 70-72 it drops about 3 tenths versus 67 mph. At 67=69 mph you will get run over on the interstate around here!
 

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Discussion Starter · #6 ·
Low speed or high speed, it increased drag, first impression before even getting on the freeway was the truck felt heavier which led me to the tests I did. Needs to be developed more, still need to go back and add the top piece to keep airflow out of the engine compartment and also want to test angling the piece to allow for a natural flow under the truck.

the V1.0 of the air dam performed the best over none and the V2.0...
 

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The tune is the base tune provided by HPT during VIN lock, the data is collected using the Andriod app Torque via a Scantool.net MX Bluetooth scanner. No adjustments for mpg are set, as in vehicle weight, tank size etc... The MPG number shown is the last average value posted in the data being looked at. I have no idea how they are calculating their mpg #'s.
I'm not angry with myself for not figuring this out sooner... just disappointed... :grin2:

You can see all this data with just the Scantool MX? I was on the fence about buying it, and may end up doing so yet today.
 

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Discussion Starter · #8 ·
You can see all this data with just the Scantool MX? I was on the fence about buying it, and may end up doing so yet today.
Yup... log the data, open with excel and then analyze it. With the test I just figured out posted earlier, letting CC handle all the throttle takes the human element out of it and allows for repeatable data. Planning to go back to that same test over the 18 miles with the 3 air dams to see how repeatable it is. I expect it to repeat.
 

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How well will this dam fare at higher speeds?
Bob beat me to it, as I thought "60 mph is a bit low for noticeable differences, I think" while reading the earlier posts.

I'd guess that testing at 80-90 mph would show more significant changes, making the analysis easier.
Okay, so while I tend to drive at those speeds, not everybody does. Still, the percentages should be valid, just easier to observe.
 

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The device does not show the data on the phone/tablet as their sales pitch shows? If not, can you screenshot what is actually available on phone so it could possibly be seen "on the fly"?
 

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Discussion Starter · #11 ·
The device does not show the data on the phone/tablet as their sales pitch shows? If not, can you screenshot what is actually available on phone so it could possibly be seen "on the fly"?
Not sure what their site shows these days but... this is live data

 

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Discussion Starter · #14 ·
I bought the Torque app for android... $5 bux IIRC... been using it for about 6 years now, same adapter. I had 2 bluetooth drops and had to re-pair it with the phone. I suspect it was the phone and not the adapter. Still... not bad for approx 6 years useage.
 
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