What does the control unit do to restrict the engine to a particular HP - Fuel delivery? RPM? - at a given RPM why should one engine give a lower power output than another? ie 50HP vs 60HP EFI 4 stroke
From the specs the only difference is in gear ratio: 1.83:1 gear ratio for the 60HP and 2.3:1 for the 50. Does this mean that for a given engine RPM, the prop speed is higher for the 60? That the 50 could drive a bigger prop and get the same power?
Argh!!! The UK Mercury dealer site publishes different gear ratios for the 50 and 60s, but the Mercury site itself specs both at 1.83:1.<br /><br />I'm still nowhere near to understanding the difference. If it is fuel delivery, how can you get an identical rev range?<br /><br />Does it mean that the 50 is understressed compared to the 60?
You can check the WOT RPM recommendation for both motors to see if their is a difference. <br /><br /> The gear ratios difference is usually to allow a family of motors to share common props.<br /><br />On a four cycle motor, compression ratio and piston dome could be the difference between the 50 and 60HP. There are also many other possible differences in the motors.
Merc is not going to release any info that would lead to a cheap 10hp boost to its EFI 50. If you want 60hp they want you to buy a 60.<br /><br />Not in the specs, that's for dang sure.
Something I noticed looking at mercury specs. is different year motors with the same pistons, CID, carberator jets, RPM range, gear rario, etc. put out differennt hp.
