1985 90hp Mariner inline 6 RPM range

[79Merc80]

Hey Guys/Gals:

I was curious about the RPM range of the 90hp inline 6.

Thanks, Craig

 

[Faztbullet]

Re: 1985 90hp Mariner inline 6 RPM range

4500-5000 rpm..

 

[79Merc80]

Re: 1985 90hp Mariner inline 6 RPM range

What is it that keep the 90 at 4500 - 5000, and the 115 5000 - 5500?

 

[Faztbullet]

Re: 1985 90hp Mariner inline 6 RPM range

Block intake & exhaust porting.

 

[sierra bayrunner]

Re: 1985 90hp Mariner inline 6 RPM range

Thanks. 4500-5000 is what I thought. I also was wondering why so much lower then most 2 stokes. That was answered as well. Thanks-- One more Question--
Im running 4900-5000 rpms. She is a bullet out of the hole and tops out at 34 mph. I am usually up at 4500 to 5500 ft elevation if that helps. Would like to gain a little more top end. Any ideas ?

 

[Faztbullet]

Re: 1985 90hp Mariner inline 6 RPM range

Boat set-up,engine height,prop brand,prop size,boat weight,type of hull all affect speed and handling. If your set up for skiing/tubing you will be slower than a set-up for fishing and speed.