Well added a new tech and made another run. Starboard tech is pretty close @4100 at full throttle 56 MPH Port is off it maxed @ 4500 at full throttle 56 MPH. So either I have a miss match on props or Starboard engine not making full power. While at full throttle I could pull the port back to 3/4 to get it to hook same rpm. Like it is pushing harder. At half throttle they are the same. I did check and the timing is the same and the blade are full open. BBlades the numbers are stamped into the nose where the spline bushing pushes in. I can't find a mark anywhere else. What do you suggest? theses are 425 hps mild build in a 38 scarab this boat should run 10 mph more, or close.

We can inspect the props to determine differences. I'm betting they are not matched.

Brett

So, in a couple of weeks, if I sent them to you, what would you charge to check them and tell me what they are? If I buy new props I would want to list / sell those to someone, who could use them, to help offset the new props. What i'm looking for are the most effecient at cruising and top end.

Visual and mechanical inspections are free. We should be able to answer most all questions via that route.

Computer aided MRI inspectins are $150 per propeller set.

Brett

Well before the end of september they will be heading your way!!

they look like the mach 1 sterndrive discontinued props,that boat stock should be able to pull 22 pitch 4 blades to 4800 5000 rpm if engines were built with the right marine parts not a street cam..do it all the time,wes/proboat marine

No STERN DRIVER cast into the inner dif ring....and the diameter looks to small as well.
But, your right they have similarities. Not sure. When those props first came out there were a variety of differences.

Brett

Don't know your History -- Blowing out at 25 ? are you triming your drives back down all the way? TRS Drives have transmissions with clutchs that can slip for whatever reasons. I agree -- first install new Tacks or a temp. tack to check your RPM at all speeds. Guess will drive you

Muscar311


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In case you are interested Autometer makes Pro- Comp Marine gauges and you can contact them at these numbers: Sales 866-2486356
Service 866-248-6357
Ask them for the marine cat.
Dont forget what I said about not hooking the sync. back up ,there is a possibility you will screw the new tachs up if you do.



Jim