Extreme makeover 72 seafari 25 aloha edition

[Bushwacker]

Originally Posted by Xcomunic8d

. . . There is the KPa. Doesn’t seem like the map KPa conversion to InHG is equivalent to your specs. A gauge may be only option. I’ve never heard of it on I/O but we use them plenty to diagnose engine health. .

5 in. Hg = 12.23 psia map (manifold absolute pressure) = 78.21 KPa. The formula for converting inches Hg to psi is: PSI = 14.69(1 - “Hg/29.92).
KPa = 6.395 x PSI

If it were me, I’d put a big 270 degree sweep 2 5/8” Vacuum gauge like this one https://www.autometer.com/2-5-8-vacu...n-hg-mech.html, above & centered between your tach & speedo! You’ll find that it’s very sensitive to engine load and health. You’ll want to be able to detect a change of 1” or less, so the more readable it is the better! I used a vacuum gage on my truck when towing and it was so sensitive on Florida’s flat roads that I could tell if I was running into a headwind or not!