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OrangeCrush
02-24-2005, 06:14 PM
What do you think is better outboards or inboards for river-lake use, Sking, tubing ,general flying when law isnt around . Iam presntly looking for new boat for my sons and cant deside witch would be better. I had both in the past.

Cp
02-24-2005, 06:22 PM
OUTBOARDS ! ! !

Kevin Turner
02-24-2005, 07:50 PM
Edit: My post is assuming you are comparing inboard jets to OB Jets, KT

I'm kinda biased myself. I'm not aware of a OB jet that can match up to the inboards of same HP for static thrust and your need static thrust to pull up a skier. The inboard cavitates less in chop and will give much better fuel economy.

200 HP Merc V6 2 stroke power head with OB Jet nets 140 HP @ impeller
Same power head on top of a mixed flow inboard jet pump @ 183 HP impeller

OrangeCrush
02-24-2005, 08:48 PM
Sorry imust have put question in the wrong thread , iment props.

150aintenuff
02-25-2005, 10:59 PM
that all depends on HOW you use the boat... pulling wakeboarders all day long at 18 MPH use inboard.. bigger wake, mre off idle torque to sustain sub planing speeds to give perfect FAT wake.. or use and OB if looking for a fast light hull that can be pulled by family car, ski and play equally as well as it can outrun those big malabu and nautique "ski boats" as well as it gives more passenger and cargo room in the boat so it only takes one trip to get everyone and everything to the beach from the ramp.... it is more in how you are going to use it that desides the power option best for you. but personaly gimme an OB anyday....

150aintenuff
02-25-2005, 11:09 PM
200 HP Merc V6 2 stroke power head with OB Jet nets 140 HP @ impeller
Same power head on top of a mixed flow inboard jet pump @ 183 HP impeller

true to a point....because merc rates their SJ"s at the impeller rather than at the nozzle a 175XR2 SJ is nearly identical to a 150 merc in prop form
a 210 SJ is a 175 Prop motor and a 240 SJ is a 200 powerhead... now to the OPTI's the 250M2 is a 225 Opti on the axial pump... and the 200 is a 175 opti engine...

The pump shows more power in axial form due to the impeller being basically bolted to the bottom of the crankshaft...

but the loss is still there as far as water to water loss in thrust. rather than steel to water as with a prop.

stoker bill
03-04-2005, 07:15 PM
Real easy, if you like working on your motor all bent over get a inboard, if you like working on your motor standing up get a outboard!!! If you do not like working on any motors stick with a sailboat.

Kevin Turner
03-04-2005, 08:24 PM
Nick, Merc rates the SJ at the impeller....

150aintenuff
03-06-2005, 07:04 AM
your right kevin... I edited my post... but the engines are still as mentioned... becaues of the gearcase losses and drive line losses in an OB prop... the SJ has some minor timing and fuel curve adjustments but basically 150=175, 175=210, 200=240 250=225... you get my point though....

and dont forget the prop is where forward thrust starts and in a jet the thrust starts pushing at the nozzle but there is some thrust due to suction from impeller that makes the difference between Axial and OB pumps... OB do not get the suction movement that the Axial pumps do...

Euroski
03-06-2005, 09:31 AM
How fast do you mean "flying"? And, how big of a boat you interested in? That said if 60mph is about all faster you want to go then buy an I/O. Probally cheaper to keep running over the years.

OrangeCrush
03-19-2005, 01:43 PM
bought checkmate enchanter 21 ft with 200 mercury thanks

Pop-O_826
03-19-2005, 02:17 PM
2 stroke outboards, I can't believe the Fed. Government, has put the X to them

150aintenuff
03-20-2005, 01:53 AM
nice boat..

and why does it surprise you that the feds took a way a perfectly acceptible engine technology.... they cant make any money on them