Nice installation!
You asked about mph display vs. the odometer.
For what it's worth, my
ScanGauge also shows a bit less speed than my HX's speedometer shows. I think the speedo's are probably set to read a bit higher than actual.
For a nice tire size calculator, go here. Will show you the % correction and dimensional differences between various tire sizes. A very handy tool.
http://www.wickedbodies.net/Tire-Size-Calculator.htm
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Check your tire pressure - keep it up !!
We've learned that diet has a closer relationship to cancer than we ever thought. Please see this Wikipedia article on
The China Study.
Driving Lean Burn '97 Civic HX, lotsa mods by now! '89 Volvo 240 is semi-retired. I did love that car though!