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bajaman
06-05-2002, 03:26 PM
New to this page but have enjoyed reading it greatly. Anyhow, Just purchased a 1986 Baja 200 SunSport with a 1986 Johnson 225VRO. I have installed a jack and have about 5 inches of setback. I am currently running a 25 pitch four blade trophy on this combo and can run about 63 mph@5800 r.p.m. Does this seem about right to you guys? I just installed a water pressure guage today so we'll try cranking the jack up a bit, but does anyone have any experiance with these hulls? How fast can it go without getting real loose? Thanks for the input...

HavasuDreamin'
06-06-2002, 06:06 AM
Bajaman.......I am coming up with a theoretical speed in the mid to upper 60's based on your set up. This tells me either your tach is not accurate or you have excessive slippage. I use the following formula..........
1. Engine RPM/Gear Ratio
2. Answer from #1 * prop pitch
3. Divide answer from #2 by 5280 then by 12
4. Multiply answer from #3 by 60
5. Factor in slippage of 10%.
Using a four blade prop, sometimes you can increase the pitch by 1 since it has so much blade surface.
Go out and get some better numbers with the jack plate. Remember to run no less than about 10 lbs. of psi on the water pressure gauge. If you do not have a nose cone with a low water pickup, you will want to have that installed so you can run the motor higher. Also, in talking with some guys who run high performance OMC motors, you will probably want to have you bearing carrier pinned into place (cross drilled). From what I hear, the OMC carrier is not a press fit like the Merc and thus they like to slide around a little bit. In the end the stress of running a surface piercing propeller tends to push the carrier out the side of the gearcase. Good Luck and happy boating!

snappertapper
06-06-2002, 05:39 PM
usually i turn more rpms on my 225 evinrude about 6100 but it sounds like a good combo to me but i would unhook the vro

bajaman
06-10-2002, 09:35 PM
Thanks for your input fellows. Took it out this week-end and ran about 65mph at 5900 rpm. I lifted my jack up about an inch and a half and i still have 8 to 10 lbs of pressure at speed. This old hull has a lot of marks in it and has been blasted from trailering fairly extensively. After I have this repaired I'm hoping to reach the 70+ mph zone. Still no predictions on how fast before this old hull explodes???