max rpm's

[sunbird]

Can anyone tell me what the maximum rpm's on a 1990 120 Johnson VRO should be. I have never exceeded 5500 and I still have a little room to go. I'm afraid if I push it I will blow the engine.

 

[Terry H]

Re: max rpm's

Sunbird...you can push that motor to 6 grand easy without harm and you should. It should also have a rev limiter on it that should keep you from over-reving. The max power on these looper motors<br />doesn't peak until somewhere after 5000rpms. Don't be concerned to use the full potential of this thing...just a Thought

 

[Spidybot]

Re: max rpm's

OMC states the WOT range to be 5000-6000.<br /><br />So far you're in the middle. If you consider another prop you'll change the rpm by 200 per inch pitch: Higher pitch = Lower rpm and vice versa.<br /><br />Go 2 inches up and you'll end near 5000-5100. This'll improve top end and mgp but hole shot will suffer. Also this will affect the sound and may remove the 'I'm afraid if I push it I will blow the engine' -feeling.<br /><br />And vice versa. <br /><br />If you want to do some interesting reading on it, visit this page

 

[sunbird]

Re: max rpm's

Thanks for the info. I'm looking foward to pushing that throttle down this weekend.

 

[Spidybot]

Re: max rpm's

Yeah. 120 hp on the prop shaft at 5500 rpm.