TOPIC: Evinrude '85 50hp tuning question

I have a 59 Glasspar Lido (14') It has a 50hp '85 Evinrude on it (e50ebco), more power than it needs but that is what it has. I am curious if there are any modifications I can make to the motor to have the boat move at a faster speed but not pushing it on to a plane. (i.e. a fast idle? or faster plow?) Right now it goes from a slow speed/idle to pushing it up out of the water to put it on plane. Nothing in between. (FYI: I'm not a motorhead) I picture a solution being where there are different throttle cams that exist? (probably not...) Maybe there are adjustments that are possible? (more likely) I'm pretty unfamiliar with all the different adjustments that are possible under the hood. I've attached a picture of what I have currently.

Any suggestions?
Thanks,
Dave

Your idle stop screw is turned almost all the way in, to the fastest idle position. This messes up the throttle linkage.

Will the engine idle slower? Have you ever tried that?

If you can get the engine to run at an acceptably slow speed in gear, without dying when you shift into gear, then your throttle pickup adjustments will probably work without having to mess with anything.

See how the throttle cam is already touching the carb roller? Where the 2 lines on the throttle cam are, is called the Primary Pickup. It's the point where the carbs are first supposed to open, upon advancing the magneto plate (which is advancing ignition timing).

Normally, you get a fair range of rotation on the mag plate, to advance timing in a smooth and progressive manner, before the throttle Primary Pickup. Then you're opening the carbs, adding even more spark advance, and getting up in the power curve.

Right now, as soon as you advance the throttle, the carbs are opening. This is why you're getting the hair-trigger action.

Note that the Primary Pickup is adjustable; you can move the carb lever that the roller is attached to by loosening the slotted screw that holds the lever in place.

You can also undo the black plastic "yoke" connection to the throttle cam by pulling the cotter pin and taking out the pin that holds it in place. You'll note that once disconnected, the yoke can be turned on the threaded rod for adjustment.

But don't make any of those adjustments yet. You want to get that idle speed setting under control.

And unless your motor is "sick", it should idle down slower. If that part is fixed, then the linkage will be more progressive.

You should be able to back off on that idle stop until the screw has about an equal amount of threads on either side of the Spark Control Lever.

If you're unable to get a lower idle adjustment, there's a way to "Band-Aid" the primary pickup so it comes on later.

But I'm thinking the idle adjustment should work and then you'll get a more normal, progressive throttle action.

After adjusting for proper idle speed, you'll have to re-adjust your throttle cable so it provides proper tension to fully close the throttle (i.e. bring the spark advance lever to rest fully on the throttle stop).

Hope that helps..............ed

p.s. see attached pic for more info.