Retrofitting an '88 Legend FE display.

[skewbe]

Originally Posted by mrmad

I don't see the circuit skewbe showed would work for what you need.

Nope, it won't. It might be useful for calibrating the vss signal (i.e. if you had different sized tires than the computer expects) though.

I think the "put it on the passenger seat and wire it up and see how it does" approach is a reasonable suggestion.

I would be tempted to do the hiway mile marker thing compared with the trip and see if there is a factor you need to multiply the miles by, then compare actual fillups to the mpg readings and see if there is a fuel consumption multiplier (divisor).

Once you know the correction factors, you should be able to calculate a displayed MPG to use as a target for your honda and know how to convert it to an accurate MPG number. So basically you drive around with a not-so-arbitrary figure in your head of what the display should say if you are trying to maintain, say, 50mpg. Throw a calculator in the glovebox if necessary along with the conversion factors but it would be good to see that it does work on it's own without investing in extra circuitry, heck it'll probably be "good enough" to be very helpful as-is.