[Hook'em_Horns!]

Okay, I used a handy little palm size offset air tool with a tapered plunging router bit, and cut open the lower side facing the front, without having to remove the intake box. I now have an unrestricted passage thru to this intake area down and between the front bumper and the inner fender. Looking thru this new inlet, to the right you can see the intake drop area.



I went ahead and cleaned the K&N, it had a few bugs but nothing major.

The result thus far is:

Limiting the intake to outside air with just the weather-stripping dropped my mileage from 9.8 to 7.8-8.3 under load but, more overall power with somewhat less fan activity and a bit cooler engine temperatures.

Opening the front now has me up to 10.3 under load, in the 13s when unloaded, and with much better performance, even cooler engine temps than after the weather-strip and the biggest change…fan activity only every now and then and much quieter when it does engage.

This was while driving in the mid 90s outside, AND it was an overall quietness that I’ve never experienced before except while driving in winter. Running long grades, the Allison is running cooler with much less shifting also, it has yet to reach 200*, and engine temperature is now staying constant with no fluctuations.

Oh, and my dog complained about the A/C being much colder, so I had to back off the temperature a few degrees.

I’ll report any additional gains, if any, when and if I’m running empty and trailer-less but now it is: up .5mpg under load and up 2mpg unloaded. (Note: Unloaded=13.5k lbs gcw, Loaded (today)=25.5k lbs gcw)

Not a whole lot, but every little bit helps at $4.50+/gal., I guess…and it runs better.