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Anyone have any experience with the 49ci Mercury 3 cyl motors from the 80's? Would it be a good lake motor on a T style boat? How about propeller availability ? All opinions appreciated. Only saw one old Merc at the Peterborough races on an Allison and it was running really good, but not sure what size it was.
Thanks

We have had THREE 49 cubic inch Mercury T750 boats. The 49 cubic inch Mercury is on probation in T750. When we started the T750 class there were several people that had those motors and wanted to race. We look at each individual boat and judge its competitiveness. If that boat is competitive with the other T750 boats then there is no problem.
There is at least on member that had a production model VooDoo [white & black?] 49 cubic inch Mercury. I believe it ran low 50's. The motor is weak compared to the stinger and Yamaha. A 56 OMC is the best of the lot.

Thanks for the info. Really the main reason for a different motor is to get power trim, it is a pain to not have it on a recreation boat. It is easier to just swap a motor than to try and add trim to the motor we already have. I figure that if switching motors we might as well go to a 3 cyl for a little more speed.

I had a 89 voodoo had a 3 cyl 2 carb merc on it. Had a 18 chopper prop on it. Top end was a little over 60 mph on gps. With the wife 50 mph. The 70 and 60 have a gear ratio of 1.64 not great out of the hole but a good top end. If you wanted a good hole shot the 40 and 50 hp 4 cyl bottom ends fit and they are 2.1 ratio. The power trim and tilt all interchange on these motors. I have two 70 hp from the early 80's that I have used the mid sections from the 40 hp 4 cyl to have the newer trim and tilt. Also these motors are not has heavy as a 70 hp omc.

FROM ANOTHER THREAD: viewtopic.php?t=2107

This quote was the reason I thought the boat ran low 50's same as a Yamaha Pro 50. We know that a Mercury can run over 60 on a race boat. It had the early 1970's kilo record of 65 mph in FE class. Over 60 with a production model VooDoo is impressive.

Great info!
How good did your Voodoo get out of the hole with the small chopper? One of my son's buddies has a mini Voodoo with 50ProV and pretty sure a chopper on it. He has to sit on the deck to get on plane, however the kid doesn't seem to know that the trim goes down too Reason I am asking about the Merc is a friend of mine has a late 80's 60hp that he has sitting around he might sell. Mid 50mph while still having decent holeshot is the goal for my son.

Out of the whole was better with the 2.1 ratio. I used it for a while on the 70 to take advantage of the whole shot and to pull the kids and grand kids on a tube.Withe the 1.64 it was not as good but top end was great. It planed out fine as long as you use the trim, just a little slower to get on plane. the chopper prop I found was great it was also cupped.I ran between 5800 and 6000 grand. I also changed the jets. Its been a long time ago but I think I went up one size so as not to lean it out. the guy that set up the boat in Port Severn suggest this since you would be running wide open all the time. I found that weight made a big difference. I ran a garden tractor battery all the time in it and a 2 gallon tank when I wanted to see how fast I could go. And I weighted about 150 lbs.

One of the best props for the 30 to 60 hp motors was the small 10 3/8 X 18 chopper that Mercury made for the 25 hp Mercury. It did not matter if the motor was a Yamaha, Tohatsu/Nissan or a Mercury. You could change the spline to fit and you could add more cup to suit your need. The props were low cost and they worked very well. I am not sure if the Mercury Chopper 11 or Ron Hills prop work as well.
The other chopper style Mercury prop that worked on the 60 hp was the 12 X 20 prop from the original 1967 Mercury BP motors . The original prop was solid hub. Mercury reworked it in 1968 to a rubber hub to run on their racing 50 hp Mercury SS to run on the NEW 2 to 1 gear case.

The 10 3/8 x18 mercury chopper prop is the one I used. It is a solid hub prop.

I had the 18" chopper and the 12X20 prop mentioned above with a 70 Nissan. A 23 SRX took it to 57.6 on my GPS. All 3 hit the rev limiter.

I miss that boat but time constraints make it pointless to replace it. When would I use a 3rd boat.