We tested our 150 Mercury four stroke on our Allison Grand Sport, and the preliminary testing is really promising. 10 MPG at 40 MPH, not bad. That was with a 28" Promax prop. 77 MPH on the rev limiter at 5940 RPM. We added ProXS mounts after the first test, which are a little stiffer, still not ideal though. It really needs solid mounts.
Engine:150 3.0L four stroke (2B444363)
Details here
https://www.wavetowave.com/home/2018...-a-mercury-150
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