Quote:
Originally Posted by JRMichler
My target speed is 54-55 MPH. The nearest 65 MPH speed limit is about 80 miles from where I mostly drive. A typical 70-75 mile trip has about 55 miles with 55 MPH limit, with the rest at speed limits 25 to 45 MPH, and four miles of narrow twisty gravel road. My average mileage on such a trip is about 5% better than MPG at a steady 55 MPH. My kill switch gets a lot of use.
My tires are 2% oversize, so current gearing is 1800 RPM at 55 MPH with a 3.73 rear end ratio. Most summer highway driving is at 6 to 9 PSI MAP, which is why I think a taller rear axle ratio would help.
I've never looked up the lubricant specs. Engine oil is whatever the 10 minute oil change place puts in.
The factory air dam is well above the low points. Underneath is a collection of huge holes, with the transmission cross member a couple inches lower than anything else.
And agree on the BSFC. When I do frontal area / Cd / rolling resistance calculations, I need to use less than 0.40 lbs/hp/hr to get calculated MPG to match real world MPG.
I doubt I'll ever do it all, but I'm sure thinking about it!
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I tried to run some numbers for the Canyon,but the lower speed mix complicates things.Taking a simple average of your winter/summer mpg increase we're looking at a 35% mpg gain.
If this were all done a steady 55-mph,we'd have to see a 70% drag reduction to explain it.
If the Canyon started at Cd 0.40,then you'd be at about Cd 0.12 according to the formulas.
If you're seeing north of 37 already in the summer,40 seems doable.
The T-100 responded really well to the nose and airdam.With the current tires,no headlight covers,none of the bellypan,and no boat tail,I'm seeing 29.6 mpg @ up to 75 mph,turning 2850 rpm.
At a maximum 70 mph,she's 30.4 mpg.She turns 2,000 rpm @ 55 mph.A sixth gear would be nice.Taller gears would probably help the Canyon as well,just as you've mentioned.The lower airdam I'm certain would help.
Some cardboard and duct tape mods might show some results as it did on the Dodge truck and CRX,and other member projects.With the OBD-II electronics it wouldn't take you long to see any changes.